Maven Integration for Eclipse

Edition 1.0 m2eclipse 0.10.0

Tim O’BrienJason van Zyl

Benjamin BentmannIgor Fedorenko

Brian FoxMilos KleintPeter Lynch

Matthew PiggottPascal Rapicault

Rich SeddonVlad TatavuDan Yocum

Developing with Eclipseand Maven

A Sonatype Open BookMountain View, CA

Copyright © 2010 Sonatype, Inc.

This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States license. For more information about this license, see http://creativecommons.org/licenses/by-nc-nd/3.0/us/. You are free to share, copy, distribute, display, and perform the work under the following conditions:

• You must attribute the work to Sonatype, Inc. with a link to http://www.sonatype.com. • You may not use this work for commercial purposes. • You may not alter, transform, or build upon this work.

Nexus™, Nexus Professional™, and all Nexus-related logos are trademarks or registered trademarks of Sonatype, Inc., in the United States and other countries. Java™ and all Java-based trademarks and logos are trademarks or registered trademarks of Sun Microsystems, Inc., in the United States and other countries. IBM® and WebSphere® are trademarks or registered trademarks of International Business Machines, Inc., in the United States and other countries. Eclipse™ is a trademark of the Eclipse Foundation, Inc., in the United States and other countries. Apache and the Apache feather logo are trademarks of The Apache Software Foundation.

Many of the designations used by manufacturers and sellers to distinguish their prod-ucts are claimed as trademarks. Where those designations appear in this book, and Sonatype, Inc. was aware of a trademark claim, the designations have been printed in caps or initial caps.

While every precaution has been taken in the preparation of this book, the publisher and authors assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein.

Published by:

Sonatype, Inc. 800 W. El Camino RealSuite 400Mountain View, CA 94040.

ISBN 978-0-9842433-1-0 Editor: Tim O’Brien

For online information and ordering of this and other Sonatype books, please visit www.sonatype.com. The publisher o�ers discounts on this book when ordered in quantity. For more information, please contact:book@sonatype.com

Copyright ........................................................................................................................................................... viiForeword: 1.1 ...................................................................................................................................................... ix

1. Changes in Edition 1.1 ............................................................................................................................... ix2. Changes in Edition 1.0 ............................................................................................................................... ix

I. Sonatype m2eclipse ............................................................................................................................................ 11. Introduction to m2eclipse ............................................................................................................................ 3

1.1. Introduction .................................................................................................................................... 31.2. m2eclipse ....................................................................................................................................... 3

2. Installing m2eclipse .................................................................................................................................... 52.1. Installing the Eclipse IDE ................................................................................................................. 52.2. Installing m2eclipse in Eclipse 3.6 (Helios) with the Eclipse Marketplace .................................................. 5

2.2.1. Installing Maven Integration for Eclipse (Core) .......................................................................... 62.2.2. Installing Maven Integration for Eclipse (Extras) Prerequisites ....................................................... 82.2.3. Installing Maven Integration for Eclipse (Extras) ........................................................................ 9

2.3. Installing m2eclipse in Eclipse 3.5 (Gallileo) ...................................................................................... 112.3.1. Installing m2eclipse Core Components .................................................................................... 112.3.2. Installing m2eclipse Extras .................................................................................................... 122.3.3. Installing Optional Prerequisites ............................................................................................. 12

2.4. Uninstalling m2eclipse from Eclipse 3.6 (Helios) with the Eclipse Marketplace ......................................... 133. Creating and Importing Projects .................................................................................................................. 17

3.1. Creating a Maven Project ................................................................................................................ 173.1.1. Checking Out a Maven Project from SCM ............................................................................... 173.1.2. Creating a Maven Project from a Maven Archetype ................................................................... 183.1.3. Creating a Maven Module ..................................................................................................... 20

3.2. Create a Maven POM File ............................................................................................................... 223.3. Importing Maven Projects ............................................................................................................... 23

3.3.1. Importing a Maven Project .................................................................................................... 243.3.2. Materializing a Maven Project ............................................................................................... 25

4. Running Maven Builds .............................................................................................................................. 294.1. Enabling the Maven Console ........................................................................................................... 294.2. Running Maven Builds ................................................................................................................... 29

5. m2eclipse Preferences ............................................................................................................................... 315.1. Maven Preferences ......................................................................................................................... 31

6. Working with Maven Repositories .............................................................................................................. 356.1. Working with Maven Repositories .................................................................................................... 356.2. Searching For Maven Artifacts and Java classes .................................................................................. 356.3. Indexing Maven Repositories ........................................................................................................... 376.4. Browsing and Manipulating Maven Repositories ................................................................................. 38

6.4.1. Opening the Maven Repository View ...................................................................................... 396.4.2. Browsing Global Repositories ................................................................................................ 406.4.3. Browsing Your Workspace Repository .................................................................................... 406.4.4. Browsing a Project Repository ............................................................................................... 416.4.5. Browsing Your Local Repository ........................................................................................... 436.4.6. Manipulating a Repository Index ............................................................................................ 43

7. Using m2eclipse ....................................................................................................................................... 457.1. ................................................................................................................................................... 45

7.1.1. Adding and Updating Dependencies and Plugins ....................................................................... 457.1.2. Downloading Source ............................................................................................................ 467.1.3. Opening Project Pages .......................................................................................................... 467.1.4. Resolving Dependencies ....................................................................................................... 46

7.2. Analyzing Project Dependencies in m2eclipse ..................................................................................... 478. Using m2eclipse ....................................................................................................................................... 51

8.1. Working with Maven Projects .......................................................................................................... 51

iv

8.1.1. Downloading Source ............................................................................................................ 528.1.2. Opening Project Pages .......................................................................................................... 528.1.3. Resolving Dependencies ....................................................................................................... 52

8.2. Using the Form-based POM Editor ................................................................................................... 528.3. Summary ...................................................................................................................................... 56

II. Maven Studio for Eclipse .................................................................................................................................. 579. Introduction to Maven Studio for Eclipse ..................................................................................................... 59

9.1. Introduction .................................................................................................................................. 599.2. Developer Onboarding .................................................................................................................... 59

9.2.1. The Cost of New Developer Onboarding ................................................................................. 599.2.2. Onboarding with Maven Studio for Eclipse: Productive on Day One ............................................. 619.2.3. Managing Developer Workspace Complexity ........................................................................... 61

9.3. Managing Change in Development Environments ................................................................................ 629.3.1. The Common Scenario: Upgrading Development Infrastructure .................................................... 639.3.2. Disadvantages of a High-Risk Development Environment ........................................................... 639.3.3. Advantages of a Low-risk Development Environment ................................................................ 64

9.4. Consolidating Project Feeds ............................................................................................................. 659.4.1. Simple Scenario: Aggregating a Project's Feeds ........................................................................ 669.4.2. Complex Scenarios: Mixed Open/Commercial Development ........................................................ 66

10. Maven Studio for Eclipse Quickstart .......................................................................................................... 6910.1. Introduction ................................................................................................................................. 69

10.1.1. What is a Codebase? .......................................................................................................... 6910.1.2. What is a Lineup? ............................................................................................................. 6910.1.3. What is a Source Tree? ....................................................................................................... 7010.1.4. What is a Source Tree Root? ............................................................................................... 7010.1.5. Use Case for a Build Engineer ............................................................................................. 70

10.2. Getting Started with Maven Studio for Eclipse .................................................................................. 7010.2.1. Nexus Team Edition Prerequisites ......................................................................................... 7110.2.2. Workstation Prerequisites .................................................................................................... 71

10.3. Installing Nexus Team Edition ........................................................................................................ 7110.3.1. Download Nexus Team Edition ............................................................................................ 7110.3.2. Unpack Nexus Team Edition ............................................................................................... 7110.3.3. Start Nexus Team Edition ................................................................................................... 7110.3.4. Login as a Nexus Administrator ........................................................................................... 71

10.4. Configure Nexus Team Server ........................................................................................................ 7210.4.1. Open the Nexus Server Configuration Panel ........................................................................... 7210.4.2. Configure Proxy Settings .................................................................................................... 7210.4.3. Save the Nexus Server Configuration .................................................................................... 7210.4.4. Add a New P2 Proxy Repository .......................................................................................... 7210.4.5. Configure the New Proxy Repository .................................................................................... 73

10.5. Run the Publish Lineups Scheduled Task in Nexus Team Server ........................................................... 7310.5.1. Execute a Scheduled Task for P2 Lineups .............................................................................. 7310.5.2. Verify P2 Lineups are Published .......................................................................................... 73

10.6. Materialize a Sample Workspace .................................................................................................... 7410.6.1. Open the Repositories Panel ................................................................................................ 7410.6.2. Select Nexus Managed Repositories ...................................................................................... 7410.6.3. Select Sonatype MSE Repository .......................................................................................... 7410.6.4. Click on the MSE Installer for the Maven Lineup .................................................................... 7410.6.5. Run the MSE Installer ........................................................................................................ 7510.6.6. Supply Server and Source Control Credentials ........................................................................ 7510.6.7. Specify Installation Directories ............................................................................................. 7610.6.8. Verify Completed Eclipse Installation .................................................................................... 7610.6.9. Configure Password Recovery .............................................................................................. 77

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10.7. Creating a New MSE Lineup ......................................................................................................... 7810.7.1. Create a New MSE Lineup Project ....................................................................................... 7810.7.2. Select the New P2 Lineup Wizard ........................................................................................ 7910.7.3. Configure Nexus and Lineup Coordinates .............................................................................. 7910.7.4. Select Runtime Platform and Memory ................................................................................... 8010.7.5. Configure the Contents of the Lineup .................................................................................... 8010.7.6. Add a New Repository ....................................................................................................... 8110.7.7. Add the Checkstyle Plugin Installable Unit ............................................................................. 8110.7.8. Verify the P2 Lineup .......................................................................................................... 81

10.8. Configuring a New Codebase ......................................................................................................... 8210.8.1. Maximize the Codebase Overview ........................................................................................ 8210.8.2. Create a New Source Tree ................................................................................................... 8310.8.3. Configure the New Source Tree ........................................................................................... 8310.8.4. Configure the SCM Location ............................................................................................... 8310.8.5. Add a Feed URL ............................................................................................................... 84

10.9. Publishing a Codebase .................................................................................................................. 8410.9.1. Publish Your Codebase to Nexus .......................................................................................... 8410.9.2. Supply Nexus Team URL and Credentials .............................................................................. 8510.9.3. Publish the Codebase ......................................................................................................... 85

10.10. Materializing a Codebase ............................................................................................................. 8510.10.1. Download the Codebase Installer ........................................................................................ 8510.10.2. Supply Apache Subversion Credentials ................................................................................ 8610.10.3. Supply Nexus Credentials .................................................................................................. 8610.10.4. Configure Materialization Directories ................................................................................... 8710.10.5. Use Your Materialized Eclipse Installation ............................................................................ 87

10.11. Troubleshooting Codebase Materialization ...................................................................................... 8810.11.1. Reset Subversion Connection ............................................................................................. 88

11. Managing MSE Codebases and P2 Lineups ................................................................................................. 8911.1. Introduction ................................................................................................................................. 8911.2. Creating a MSE Codebase ............................................................................................................. 89

11.2.1. Creating a New P2 Lineup .................................................................................................. 8911.2.2. Creating a New MSE Codebase ........................................................................................... 92

11.3. Configuring a MSE Codebase ........................................................................................................ 9211.4. Configuring Codebase Information .................................................................................................. 9411.5. Managing Codebase Resource Locations .......................................................................................... 95

11.5.1. Publishing Eclipse Preferences ............................................................................................. 9611.5.2. Publishing Maven Settings .................................................................................................. 96

11.6. Setting Codebase Prerequisites ........................................................................................................ 9711.7. Managing Codebase Source Trees ................................................................................................... 9711.8. Configuring Codebase Security ....................................................................................................... 9811.9. Configuring a Source Tree ............................................................................................................. 98

11.9.1. Adding a Maven Profile .................................................................................................... 10011.9.2. Adding a New Feed URL .................................................................................................. 100

11.10. Publishing an MSE Codebase to Nexus Team Edition ..................................................................... 100A. Creative Commons License ............................................................................................................................. 103

A.1. Creative Commons BY-NC-ND 3.0 US License ....................................................................................... 103B. Book Revision History .................................................................................................................................... 107

B.1. Changes in Edition 0.8 ......................................................................................................................... 107B.2. Changes in Edition 0.7 ......................................................................................................................... 107B.3. Changes in Edition 0.6 ......................................................................................................................... 107

Index ................................................................................................................................................................ 109

CopyrightCopyright © 2010 Sonatype, Inc.

Online version published by Sonatype, Inc., 800 W. El Camino Real, Suite 400, Mountain View, CA, 94040.

This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States license. Formore information about this license, see http://creativecommons.org/licenses/by-nc-nd/3.0/us/.

Nexus™, Nexus Professional™, and all Nexus-related logos are trademarks or registered trademarks of Sonatype, Inc., in the UnitedStates and other countries.

Java™ and all Java-based trademarks and logos are trademarks or registered trademarks of Sun Microsystems, Inc., in the UnitedStates and other countries.

IBM® and WebSphere® are trademarks or registered trademarks of International Business Machines, Inc., in the United States andother countries.

Eclipse™ is a trademark of the Eclipse Foundation, Inc., in the United States and other countries.

Apache and the Apache feather logo are trademarks of The Apache Software Foundation.

Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where thosedesignations appear in this book, and Sonatype, Inc. was aware of a trademark claim, the designations have been printed in capsor initial caps.

While every precaution has been taken in the preparation of this book, the publisher and authors assume no responsibility for errorsor omissions, or for damages resulting from the use of the information contained herein.

Foreword: 1.1You are encouraged to check http://books.sonatype.com/m2eclipse-book weekly for any updates to the content. If you would liketo receive updates whenever there is a change to this user's manual, please send a quick note to book@sonatype.com1, and we willgladly add your email to the update notification list.

We welcome your feedback, please do not hesitate to contact the Sonatype team with any questions or ideas you may have aboutthe product.

Tim O'Brien, Sonatype

July, 2010

Edition: 1.1

1. Changes in Edition 1.1The following changes were introduced in Edition 1.1 in July, 2010:

• Added Section 2.2, “Installing m2eclipse in Eclipse 3.6 (Helios) with the Eclipse Marketplace”

2. Changes in Edition 1.0The following changes were introduced in Edition 1.0 in June 2010:

• Added a new part to the book on Maven Studio for Eclipse.

• Added Maven Studio for Eclipse chapters to the book.

• Chapter 9, Introduction to Maven Studio for Eclipse

• Chapter 10, Maven Studio for Eclipse Quickstart

• Chapter 11, Managing MSE Codebases and P2 Lineups

1 mailto:book@sonatype.com

Part I. Sonatype m2eclipseThe first portion of this book deals with the Sonatype m2eclipse plugin.

Chapter 1. Introduction to m2eclipse1.1. IntroductionThe Eclipse IDE is the most widely used IDE for Java development today. Eclipse has a huge amount of plugins (see http://www.eclipseplugincentral.com/) and an innumerable amount of organizations developing their own software on top of it. Quitesimply, Eclipse is ubiquitous. The m2eclipse1 project, provides support for Maven within the Eclipse IDE, and, in this chapter, wewill explore the features it provides to help you use Maven with Eclipse.

1.2. m2eclipseThe m2eclipse plugin (http://m2eclipse.sonatype.org/) provides Maven integration for Eclipse. m2eclipse also has hooks intothe features of both the Subclipse plugin (http://subclipse.tigris.org/) and the Mylyn plugin (http://www.eclipse.org/mylyn/). TheSubclipse plugin provides the m2eclipse plugin with the ability to interact with Subversion repositories, and the Mylyn plugin providesthe m2eclipse plugin with the ability to interact with a task-focused interface that can keep track of development context. Just a fewof the features m2eclipse provides include:

• Creating and importing Maven projects

• Dependency management and integration with the Eclipse classpath

• Automatic dependency downloads and updates

• Artifact Javadoc and source resolution

• Creating projects with Maven Archetypes

• Browsing and searching remote Maven repositories

• POM management with automatic update to dependency list

• Materializing a project from a Maven POM

• Checking out a Maven project from several SCM repositories

• Adapting nested multi-module Maven projects to the Eclipse IDE

• Integration with Web Tools Project (WTP)

• Integration with Subclipse

• Integration with Mylyn

• Form-based POM Editor

• Graphical Display of Dependency Graph

• GUI Presentation of Dependency Tree and Resolved Dependencies

There are many more features in m2eclipse beyond the list above and this chapter introduces some of the more impressive featuresthat are currently available. Let’s get started by installing the m2Eclipse plugin.

1 http://m2eclipse.codehaus.org/

Chapter 2. Installing m2eclipse2.1. Installing the Eclipse IDE

Sonatype recommends installing m2eclipse on Eclipse 3.5 or Eclipse 3.6, and to make use of m2eclipse you will need to install theJDK. To download an Eclipse IDE distribution:

1. Go to http://www.eclipse.org/downloads/ in a web browser.

2. Download an Eclipse distribution. Note: If you want to use the m2eclipse WTP integration, download the Eclipse IDE forJavaEE Developers distribution.

3. Install Eclipse - for more information about installing the Eclipse IDE, see the Eclipse Wiki1.

2.2. Installing m2eclipse in Eclipse 3.6 (Helios) with the EclipseMarketplace

The Eclipse Marketplace makes it easy to install m2eclipse and m2eclipse (Extras) in Eclipse 3.6 (Helios). To open the EclipseMarketplace, go to the Eclipse Help menu and select Eclipse Marketplace... as shown in Figure 2.1, “Opening the EclipseMarketplace”.

Figure 2.1. Opening the Eclipse Marketplace

The first time you open the Eclipse Marketplace, you will be asked to select a Marketplace. Select the Eclipse Marketplace as shownin Figure 2.2, “Selecting the Eclipse Marketplace”.

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Figure 2.2. Selecting the Eclipse Marketplace

2.2.1. Installing Maven Integration for Eclipse (Core)

Maven Integration for Eclipse is separated into two components: the Core of Maven Integration for Eclipse and an optional packageof extra, unsupported components. To install the core component of Maven Integration for Eclipse, open the Eclipse Marketplace,select the Search tab, and search for "Maven Integration" as shown in Figure 2.3, “Selecting Maven Integration for Eclipse fromEclipse Marketplace”. Click on the Install button to the right of the second item listed in Figure 2.3, “Selecting Maven Integrationfor Eclipse from Eclipse Marketplace”.

Figure 2.3. Selecting Maven Integration for Eclipse from Eclipse Marketplace

Once you click on Install, Eclipse will download a list of available components from the remote update site and present you with a listof available features in the Maven Integration for Eclipse plugin as shown in Figure 2.4, “Selecting the Core m2eclipse Feature forInstallation”. Select the single, required component named "Maven Integration for Eclipse (Required)", and click on the Finish button.

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Figure 2.4. Selecting the Core m2eclipse Feature for Installation

Eclipse will then ask you to agree to the licenses for Maven Integration for Eclipse in the Review Licenses step shown in Figure 2.5,“Agreeing to Software License During m2eclipse Installation”. Maven Integration for Eclipse is distributed under the Eclipse PublicLicense version 1.0. If you agree with the conditions of this license, select "I accept the terms of the license agreement" and clickon the Finish button.

Figure 2.5. Agreeing to Software License During m2eclipse Installation

During the installation process, Eclipse may warn you that the software you are installing contains "unsigned content". If you see thedialog shown in Figure 2.6, “Ignoring Warning During m2eclipse Installation”, click on OK to continue the installation process.

Figure 2.6. Ignoring Warning During m2eclipse Installation

Once m2eclipse has been installed, Eclipse will prompt you to either restart or apply changes to a running Eclipse. At this stage ofthe installation, you should click on Restart Now to restart your Eclipse instance. After a successful restart, Maven Integration forEclipse will be installed.

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Figure 2.7. Restarting Eclipse after m2eclipse Installation

2.2.2. Installing Maven Integration for Eclipse (Extras) Prerequisites

The Maven Integration for Eclipse extra components provide support for additional tools like the Web Tools Project (WTP),Subversion integration via Subclipse, and integration with Mylyn. The following sections provide guidance for users installing someof the prerequisites for m2eclipse extra components.

2.2.2.1. Installing Subclipse in the Eclipse Marketplace

To install Subclipse in the Eclipse Marketplace, open the Marketplace, select the Search tab, and search for "Subclipse" to see thedialog shown in Figure 2.8, “Selecting Subclipse from the Eclipse Marketplace”. Click on Install next to the Subclipse search resultitem.

Figure 2.8. Selecting Subclipse from the Eclipse Marketplace

Select the appropriate Subclipse components, agree to the software license for Subclipse, and restart your Eclipse installation afterthe installation process is completed.

2.2.2.2. Installing Mylyn in the Eclipse Marketplace

To install Mylyn in the Eclipse Marketplace, open the Marketplace, select the Search tab, and search for "Mylyn" to see the dialogshown in Figure 2.9, “Selecting Mylyn from the Eclipse Marketplace”. Click on Install next to the Mylyn search result item.

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Figure 2.9. Selecting Mylyn from the Eclipse Marketplace

Select the appropriate SMylyn components, agree to the software license for Mylyn, and restart you Eclipse installation after theinstallation process is completed.

2.2.3. Installing Maven Integration for Eclipse (Extras)

To install the extra components for Maven Integration for Eclipse, open the Eclipse Marketplace, select the Search tab, and searchfor Maven Integration to see the search results shown in Figure 2.10, “Selecting Maven Integration for Eclipse (Extras) from theEclipse Marketplace”. CLick on Install next to the "Maven Integration for Eclipse (Extras)" search result item.

Figure 2.10. Selecting Maven Integration for Eclipse (Extras) from the Eclipse Marketplace

Once you have clicked on Install, Eclipse will download the list of available plugin components from the remote update site. The listof available components will then be displayed in the Confirm Select Features step as shown in Figure 2.11, “Selecting m2eclipse(Extras) Components to Install”. The components available in the Maven Integration for Eclipse (Extras) site are:

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M2Eclipse Extensions Development Suppport (Optional)Install this component if you want to develop custom pages in the POM Editor, create custom actions in the Maven popupmenu, provide custom templates in the POM XML editor, or make other customizations to m2eclipse.

Maven Integration for WTP (Optional)If you are developing applications using the Eclipse Web Tools Project, this component will adapt the Maven classpathcontainer and other Maven resources to the WTP standards.

Maven issue tracking configurator for Mylyn 3.x (Optional)Maven can be configured to work with Mylyn a comprehensive issue and time tracking plugin which currently ships withthe Eclipse IDE.

Maven SCM handler for Subclipse (Optional)Subclipse is a popular Subversion plugin for Eclipse hosted by the Tigris community. If you want to use Maven with Subclipse,this component will provide the necessary integration between the two plugins.

Maven SCM handler for Team/CVS (Optional)This component provides integration between the m2eclipse plugin and the CVS support built into Eclipse.

Maven SCM Integration (Optional)This component is required if you installed one of the previous plugins (Subclipse or Team/CVS)

Project configurators for commonly used maven plugins (temporary)This is a temporary project which contains project configurators for commonly used Maven Plugins.

Figure 2.11. Selecting m2eclipse (Extras) Components to Install

Once you have selected the features you wish to install, click Next. Clicking Next will bring you to the Review Licenses step as shownin Figure 2.12, “Agreeing to Software License During m2eclipse (Extras) Installation”. The m2eclipse Extras is distributed underthe Eclipse Public License version 1.0. If you agree to this open source license, select "I accept the terms of the license agreement"and click on "Finish".

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Figure 2.12. Agreeing to Software License During m2eclipse (Extras) Installation

During the installation process for the m2eclipse Extras, you may receive some warning that "you are installing software that containsunsigned content". If you see the dialog shown in Figure 2.13, “Ignoring Warning During m2eclipse (Extras) Installation”, click OKto continue the installation process.

Figure 2.13. Ignoring Warning During m2eclipse (Extras) Installation

Once the installation process is finished, Eclipse will prompt you to apply the changes or restart your Eclipse instance with a dialogshown in Figure 2.14, “Restarting Eclipse after m2eclipse (Extras) Installation”. To complete the installation of m2eclipse (Extras),restart your Eclipse instance.

Figure 2.14. Restarting Eclipse after m2eclipse (Extras) Installation

2.3. Installing m2eclipse in Eclipse 3.5 (Gallileo)

2.3.1. Installing m2eclipse Core Components

To install m2eclipse, use the following Eclipse update site to install the core of the m2eclipse plugin. This Core update site containsa single component: "Maven Integration for Eclipse (Required)". When you install this component you will be installing all of thecore Wizards, the POM Editor, Maven Repository integration, and Maven integration:

• m2eclipse Plugin: http://m2eclipse.sonatype.org/sites/m2e

To install this plugin in the Eclipse IDE:

1. Select Help > Install New Software. This should display the "Install" dialog.

12

2. Paste the Update Site URL into the field named "Work with:" and press Enter. Pressing Enter should cause Eclipse to updatelist of available plugins and components.

3. Choose the component listed under m2eclipse: "Maven Integration for Eclipse (Required)".

4. Click Next. Eclipse will then check to see if there are any issues which would prevent a successful installation.

5. Click Next and agree to the terms of the Eclipse Public License v1.0.

6. Click Finish to begin the installation process.

Eclipse will then download and install the necessary components. Once the installation process is finished, Eclipse will ask you ifyou want to restart the IDE. Sonatype strongly recommends that you restart your IDE after installing m2eclipse.

Warning

You cannot upgrade from m2eclipse 0.9 to m2eclipse 0.10. If you are running m2eclipse 0.9.8 or 0.9.9 you must eitheruninstall m2eclipse from your Eclipse installation or start with a fresh installation of Eclipse.

If you've installed the plugin successfully, you should see a Maven option in the list of preference categories when you go to Window,Preferences....

2.3.2. Installing m2eclipse Extras

In addition to the core m2eclipse components, the following optional components are available from a separate update site. If youplan to use m2eclipse to materialize projects from Subversion or CVS, integrate Maven with the Eclipse Web Tools Project (WTP),or use the m2eclipse Mylyn integration you will need to install the following, extra components:

• Maven SCM Integration

• Maven SCM handler for Team/CVS

• Maven SCM handler for Subclipse

• Maven issue tracking configurator for Mylyn 3.x

• Maven Integration for WTP

• M2Eclipse Extensions Development Support

To install optional m2eclipse components, use the m2eclipse Extras update site. This update site contains the following m2eclipsecomponents:

• m2eclipse Extras Update Site: http://m2eclipse.sonatype.org/sites/m2e-extras

2.3.3. Installing Optional Prerequisites

Several of the extra components listed in the previous section require third-party plugins to be installed prior to installation. Youcan install these prerequisites when you install m2eclipse, just add a new remote update site to Eclipse for each of the prerequisitecomponents.

To install these prerequisites, select Help, Install New Software... which will load the "Software Updates and Add-ons" dialog. Inthis dialog, choose the Available Software panel and click on Add Site... which will load the simple "Add Site" dialog. Enter theURL of the update site you wish to add and click OK. In the "Software Updates and Add-ons" dialog, the available plugins froman update site will appear as soon as the site is added. You can then select the modules you want to install and click the Install...button. Eclipse will then resolve all the dependencies for the selected plugins, and ask you to agree to the plugin license. After Eclipseinstalls new plugins, you should restart the IDE.

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2.3.3.1. Installing Subclipse

When you install Subclipse, you will need to make a decision about Subversion compatibility. If you are using Subversion 1.5.xclient features, you will need to install Subclipse version 1.4. If you are using Subversion 1.6.x client features, you will need toinstall Subclipse version 1.6.

To install Subclipse, use one of the Eclipse plugin update sites listed below.

• Subclipse 1.4 (for Subversion 1.5 compatibility): http://subclipse.tigris.org/update_1.4.x

• Subclipse 1.6 (for Subversion 1.6 compatibility): http://subclipse.tigris.org/update_1.6.x

For other versions of Subclipse, and for more information about the Subclipse plugin, please see the Subclipse project's web siteat http://subclipse.tigris.org/.

2.3.3.2. Installing Mylyn

To install JIRA or Trac integration with Mylyn, add the Mylyn extras Eclipse update URL, you'll want to do this if your organizationuses Atlassian's JIRA2 for issue tracking. To install Mylyn use the following update sites:

• Mylyn (Eclipse 3.4, 3.5, and 3.6M4): http://download.eclipse.org/tools/mylyn/update/e3.4

• Mylyn Extras (JIRA and Trac Support): http://download.eclipse.org/tools/mylyn/update/extras

For more information about the Mylyn project, see the Mylyn project's web site at http://www.eclipse.org/mylyn/.

2.3.3.3. Installing the Web Tools Platform (WTP)

To install the Web Tools Platform (WTP). Install the "Eclipse IDE for Java EE Developers" from http://www.eclipse.org/downloads/,or download a WTP release from http://download.eclipse.org/webtools/downloads/.

For more information about the Web Tools Platform, see the Web Tools Platform project's web site at http://www.eclipse.org/webtools/.

2.4. Uninstalling m2eclipse from Eclipse 3.6 (Helios) with the EclipseMarketplace

To uninstall m2eclipse and m2eclipse (Extras) from Eclipse 3.6 (Helios), open up the Eclipse Marketplace by selecting EclipseMarketplace from the Eclipse Help menu. Once you have the Eclipse Marketplace dialog open, select the Installed tab as shown inFigure 2.15, “Selecting Maven Integration for Eclipse Components to Uninstall”. To uninstall either "Maven Integration for Eclipse"or "Maven Integration for Eclipse (Extras)", click on the "Uninstall" button next to each item.

2 http://www.atlassian.com/software/jira/

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Figure 2.15. Selecting Maven Integration for Eclipse Components to Uninstall

If you are uninstalling "Maven Integration for Eclipse", the Eclipse IDE will prompt you to select the feature you wish to uninstall asshown in Figure 2.16, “Selecting Components to Install for Maven Integration for Eclipse Installation”. Select the feature to uninstall,and click on Next to continue.

Figure 2.16. Selecting Components to Install for Maven Integration for Eclipse Installation

If you are uninstalling "Maven Integration for Eclipse (Extras)", the Eclipse IDE will prompt you to select the features you wish touninstall as shown in Figure 2.17, “Selecting Maven Integration for Eclipse (Extras) Features to Uninstall”. Select the features touninstall, and click on "Finish" or "Next".

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Figure 2.17. Selecting Maven Integration for Eclipse (Extras) Features to Uninstall

Once the uninstallation has successfully completed, Eclipse will prompt you to either apply changes or restart. To complete theuninstallation process, click on "Restart Now".

Figure 2.18. Restarting Eclipse after Uinstallation

Chapter 3. Creating and Importing Projects3.1. Creating a Maven Project

When using Maven, project creation takes place through the use of a Maven archetype. In Eclipse, project creation takes place via thenew project wizard. The new project wizard inside of Eclipse offers a plethora of templates for creating new projects. The m2eclipseplugin improves upon this wizard to provide the following additional capabilities:

• Checking out a Maven project from a SCM repository

• Creating a Maven project using a Maven archetype

• Creating a Maven POM file

As shown in Figure 3.1, “Creating a New Project with m2eclipse Wizards”, all three of these options are important to developersusing Maven. Let’s take a look at each one.

Figure 3.1. Creating a New Project with m2eclipse Wizards

3.1.1. Checking Out a Maven Project from SCM

m2eclipse provides the ability to check out a project directly from a SCM repository. Simply enter the SCM information for a projectand it will check it out for you to a location of your choice as shown in Figure 3.2, “Checkout a New Project from Subversion”:

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Figure 3.2. Checkout a New Project from Subversion

There are additional options in this dialog for specifying a particular revision by browsing the revisions in a Subversion repositoryor by simply entering the revision number manually. These features reuse of some of the features in the Subclipse plugin to interactwith the Subversion repository. The m2eclipse plugin supports the following SCM providers:

• Bazaar

• Clearcase

• CVS

• git

• hg

• Perforce

• Starteam

• Subversion

• Synergy

• Visual SourceSafe

3.1.2. Creating a Maven Project from a Maven Archetype

m2eclipse offers the ability to create a Maven project using a Maven Archetype. There are many Maven Archetypes provided in thelist that comes with m2eclipse as shown in Figure 3.3, “Creating a New Project with a Maven Archetype”.

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Figure 3.3. Creating a New Project with a Maven Archetype

The list of archetypes in Figure 3.3, “Creating a New Project with a Maven Archetype” is a list generated by something called theNexus Indexer. Nexus is a repository manager which is introduced in "Repository Management with Nexus", a free book availablefrom Sonatype which can be read online here: http://www.sonatype.com/books/nexus-book/reference/1. The Nexus indexer is a filewhich contains an index of the entire Maven repository, and m2eclipse uses it to list all of the available archetypes in the entireMaven repository. When this chapter was last updated, m2eclipse had approximately ninety archetypes in this Archetype dialog.Highlights of this list include:

• Standard Maven Archetypes to create

• Maven Plugins

• Simple Web Applications

• Simple Projects

• New Maven Archetypes

• Databinder2 Archetypes (data-driven Wicket Applications) under net.databinder

• Apache Cocoon3 Archetypes under org.apache.cocoon

• Apache Directory Server4 Archetypes under org.apache.directory.server

• Apache Geronimo5 Archetypes under org.apache.geronimo.buildsupport

• Apache MyFaces6 Archetypes under org.apache.myfaces.buildtools

• Apache Tapestry7 Archetypes under org.apache.tapestry

• Apache Wicket8 Archetypes under org.apache.wicket

1 ???

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• AppFuse9 Archetypes under org.appfuse.archetypes

• Codehaus Cargo10 Archetypes under org.codehaus.cargo

• Codehaus Castor11 Archetypes under org.codehaus.castor

• Groovy-based Maven Plugin12 Archetypes (deprecated)19 under org.codehaus.mojo.groovy

• Jini Archetypes

• Mule13 Archetypes under org.mule.tools

• Objectweb Fractal14 Archetypes under org.objectweb.fractal

• Objectweb Petals15 Archetypes under org.objectweb.petals

• ops4j Archetypes under org.ops4j

• Parancoe16 under org.parancoe

• slf4j Archetypes under org.slf4j

• Springframework17 OSGI and Web Services Archetypes under org.springframework

• Trails Framework18 Archetypes under org.trailsframework

19And these were just the archetypes that were listed under the Nexus Indexer Catalog, if you switch Catalogs you'll see otherarchetypes. While your results may vary, the following additional archetypes were available in the Internal Catalog:

• Atlassian Confluence20 Plugin Archetype under com.atlassian.maven.archetypes

• Apache Struts21 Archetypes under org.apache.struts

• Apache Shale Archetypes under org.apache.shale

A catalog is simply a reference to a repository index. You can manage the set of catalogs that the m2eclipse plugin knows aboutby clicking on the Configure... button next to the catalog drop down. If you have your own archetypes to add to this list, you canclick on Add Archetype....

Once you choose an archetype, Maven will retrieve the appropriate artifact from the Maven repository and create a new Eclipseproject with the selected archetype.

3.1.3. Creating a Maven Module

m2eclipse provides the ability to create a Maven module. Creating a Maven module is almost identical to creating a Maven projectas it also creates a new Maven project using a Maven archetype. However, a Maven module is a subproject of another Maven projecttypically known as a parent project.

19Don't use the Groovy Maven Plugin in Codehaus' Mojo project. Jason Dillon has moved the Groovy Maven integration to the Groovy project in codehaus. Formore information see http://groovy.codehaus.org/GMaven.

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Figure 3.4. Creating a New Maven Module

When creating a new Maven module you must select a parent project that already exists inside of Eclipse. Clicking the browse buttondisplays a list of projects that already exist as shown in Figure 3.5, “Selecting a Parent Project for a New Maven Module”:

Figure 3.5. Selecting a Parent Project for a New Maven Module

After selecting a parent project from the list, you are returned to the New Maven Module window and the Parent Project field ispopulated as shown in Figure 3.4, “Creating a New Maven Module”. Clicking Next will then display the standard list of archetypes

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from Section 3.1.2, “Creating a Maven Project from a Maven Archetype” so you can choose which one should be used to createthe Maven module.

3.2. Create a Maven POM FileAnother important feature m2eclipse offers is the ability to create a new Maven POM file. m2eclipse provides a wizard to easilycreate a new POM file inside of a project that is already in Eclipse. This POM creation wizard is shown in Figure 3.6, “Creatinga New POM”:

Figure 3.6. Creating a New POM

Creating a new Maven POM is just a matter of selecting a project, entering the Group Id, Artifact Id, Version, choosing the Packagingtype, and providing a Name into the fields provided and m2eclipse. Click the Next button to start adding dependencies.

Figure 3.7. Adding Dependencies to a New POM

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As you can see in Figure 3.7, “Adding Dependencies to a New POM” here are no dependencies in the POM yet. Just click the Addbutton to query the central Maven repository for dependencies as shown next in Figure 3.8, “Querying the Central Repository forDependencies”:

Figure 3.8. Querying the Central Repository for Dependencies

Querying for dependencies is as easy as entering the groupId for the artifact you need. Figure 3.8, “Querying the Central Repositoryfor Dependencies” shows a query for org.apache.commons with commons-vfs expanded to see which versions are available.Highlighting the 1.1-SNAPSHOT version of commons-vfs and clicking OK takes you back to the dependency selection where youcan either query for more artifacts or just click finish to create the POM. When you search for dependencies, m2eclipse is making useof the same Nexus repository index that is used in the Nexus Repository Manager, a repository manager introduced in "RepositoryManagement with Nexus" (http://www.sonatype.com/books/nexus-book/reference/).

Now that the you’ve seen the m2eclipse features for creating a new project, let’s look at a similar set of features for importing projectsinto Eclipse.

3.3. Importing Maven Projects

m2eclipse provides three options for importing a Maven project into Eclipse including:

• Import an existing Maven project

• Check out a Maven project from SCM

• Materialize a Maven project

Figure 3.9, “Importing a Maven Project” shows the wizard for importing projects with the options for Maven provided by m2eclipse:

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Figure 3.9. Importing a Maven Project

The dialog in Figure 3.9, “Importing a Maven Project” is displayed by using the File, Import command in Eclipse and then filteringthe options by entering the word maven in the filter field. As noted above, there are three options available for importing a Mavenproject into Eclipse including: Maven Projects, Check out Maven Project from Subversion, and Materialize Maven Projects.

Importing a Maven project from Subversion is identical to the creation of a Maven project from Subversion as discussed in theprevious section so discussion of it would be redundant. Let’s move on now to review the other two options for importing a Mavenproject into Eclipse.

3.3.1. Importing a Maven Project

m2eclipse can import a Maven project with an existing pom.xml. By pointing at the directory where a Maven project is located,m2eclipse detects all the Maven POMs in the project and provides a hierarchical list of them as shown in Figure 3.10, “Importinga Multi-module Maven Project”.

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Figure 3.10. Importing a Multi-module Maven Project

Figure 3.10, “Importing a Multi-module Maven Project” displays the view of the project being imported. Notice that all the POMsfrom the project are listed in a hierarchy. This allows you to easily select which POMs (and therefore which projects) that you wantto be imported into Eclipse. Once you select the project you would like to import, m2eclipse will import and build the project(s)using Maven.

3.3.2. Materializing a Maven Project

m2eclipse also offers the ability to "materialize" a Maven project. Materialization is similar to the process of checking out a Mavenproject from Subversion, but instead of manually entering the URL to the project’s Subversion repository, the Subversion URL isdiscovered from the project’s root POM file. You can use this feature to "materialize" projects from nothing more than a POM fileif the POM file has the appropriate elements to specify the location of a source repository. Using this feature, you can browse thecentral Maven repository for projects, and materialize them into Eclipse projects. This comes in handy if your project depends on athird-party open source library, and you need to get your hands on the source code. Instead of tracking down the project web site andfiguring out how to check it out of Subversion, just use the m2eclipse project to magically "materialize" the Eclipse project.

Figure 3.11, “Materializing a Maven Project” shows the wizard after choosing to materialize Maven projects:

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Figure 3.11. Materializing a Maven Project

Notice that the dialog box for Maven artifacts in Figure 3.11, “Materializing a Maven Project” is empty. This is because no projectshave been added yet. In order to add a project, you must click the Add button on the right side and select a dependency to add fromthe central Maven repository. Figure 3.12, “Selecting Artifact to Materialize” shows how to add a project:

Figure 3.12. Selecting Artifact to Materialize

Upon entering a query, candidate dependencies will be located in the local Maven repository. After a few seconds of indexing thelocal Maven repository, the list of candidate dependencies appears. Select the dependency to add and click OK so that they are addedto the list as shown in Figure 3.13, “Materializing Apache Camel”.

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Figure 3.13. Materializing Apache Camel

Upon adding a dependency, you have the option of telling the m2eclipse plugin to check out all projects for the artifact.

Chapter 4. Running Maven Builds4.1. Enabling the Maven ConsoleBefore we begin to examine the features of m2eclipse, let’s first enable the Maven console. Open the Console View by going toWindow, Show View, Console. Then click on the little arrow on the right-hand side of the Open Console icon and select MavenConsole as shown below:

Figure 4.1. Enabling the Maven Console in Eclipse

Maven Console shows the Maven output that normally appears on the console when running Maven from the command line. It isuseful to be able to see what Maven is doing and to work with Maven debug output to diagnose issues.

4.2. Running Maven Buildsm2eclipse modified the Run As... and Debug As... menus to allow you to run a Maven build within Eclipse. Figure 4.2, “Runningan Eclipse build with Run As..” shows the Run As... menu for an m2eclipse project. From this menu you can run one of the morecommon lifecycle phases like clean, install, or package. You can also load up the Run configuration dialog window and configurea Maven build with parameters and more options.

Figure 4.2. Running an Eclipse build with Run As..

If you need to configure a Maven build with more options, you can choose Run Configurations... and create a new Maven build.Figure 4.3, “Configuring a Maven Build as a Run Configuration” shows the Run dialog for configuring a Maven build.

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Figure 4.3. Configuring a Maven Build as a Run Configuration

The Run configuration dialog allows you to specify multiple goals and profiles, it exposes options like "skip tests" and "updatesnapshots", and allows you to customize everything from the project to the JRE to the environment variable. You can use this dialogto support any custom Maven build that you wish to launch with m2eclipse.

Chapter 5. m2eclipse Preferences5.1. Maven Preferences

The ability to adjust the Maven preferences and some Maven options is an important aspect of developing with Maven and m2eclipseoffers the ability to tweak these items via the Maven preferences page inside of Eclipse. Typically when using Maven on the commandline, such preferences and options are available from files in your ~/.m2 directory and as command line options. m2eclipse providesaccess to some of the most important preferences and options from the Eclipse IDE. Figure 5.1, “Maven Preferences for Eclipse”shows the Maven preferences page in Eclipse:

Figure 5.1. Maven Preferences for Eclipse

The check boxes in the top section provide the ability to:

• Run Maven in Offline mode, disabling any downloads from remote repositories

• Enable Debug output in the Maven Console

• Download Source jars for artifacts from remote Maven repositories

• Download JavaDoc jars for artifacts from remote Maven repositories

• Download and Update local indexes for remote repositories on startup

The next section offers a pop-up menu to select which goal you’d like to be executed when a project is imported and when the sourcefolders for a given project are updated. The default goal is named process-resources which copies and process the resources forthe project into the destination directory to make the project ready for packaging. Customizing this list of goals can come in handyif you need to run any custom goals which process resources or generate supporting configuration.

If you need help selecting a goal, click the Select... button to see the "Goals" dialog. The dialog on the left-hand side ofFigure 5.2,“Maven Goal Dialogs” shows the Goals dialog with a list of all the phases in the default Maven lifecycle.

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Figure 5.2. Maven Goal Dialogs

When you see the Goals dialog for the first time, there's a chance you might be overwhelmed by the number of goals it lists. Thereare literally hundreds of Maven plugins for everything from generating a database, to running integration tests, to performing staticanalysis, to generating web services with XFire. There are over two hundred plugins with selectable goals in the Goals dialog, thedialog on the right-hand side ofFigure 5.2, “Maven Goal Dialogs” shows the "Goals" dialog with the Tomcat Maven plugin's goalshighlighted. You can always narrow the list of goals shown in this dialog by typing in some text to the search dialog, as you type intext, m2eclipse is going to narrow the list of available goals to goals which contain the text in the search field.

Another Maven preference page is the Maven Installations configuration page shown in Figure 5.3, “Maven Installations PreferencePage”:

Figure 5.3. Maven Installations Preference Page

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This page allows you to add other Maven installations to the Eclipse environment. If you want to use a different version of Mavenwith the m2eclipse plugin you can configure multiple installations of Maven from this configuration page, this is very similar to theability to add more than one Java Virtual Machine to be run inside of Eclipse. An embedded version of the Maven known as theMaven Embedder is already specified. This is what is used to execute Maven inside of Eclipse. If you have another installation ofMaven which you would like to use instead of the Maven Embedder, you can add another Maven runtime by clicking on the Add..button. Figure 5.3, “Maven Installations Preference Page” shows a configuration page that lists the Maven Embedder, Maven 2.0.9,and an installation of Maven 2.1-SNAPSHOT.

The Installations configuration page also allows you to specify the location of the global Maven settings file. If you do not specifythe location of this file on this configuration page, Maven will use the default global settings file found in conf/settings.xmlof the selected Maven installation. You can also customize the location of your user settings file from the default location of~/.m2/settings.xml, and you can customize the location of your local Maven repository from the default location of ~/.m2/repository.

Also available in the Eclipse preferences is the ability to enable a decorator named the Maven Version Decorator. This preferenceprovides a given project’s current version on the Eclipse Package Explorer and is shown in Figure 5.4, “Enabling the Maven VersionDecorator”.

Figure 5.4. Enabling the Maven Version Decorator

To enable this preference, simply check the Maven Version Decorator option that is highlighted in Figure 5.4, “Enabling the MavenVersion Decorator”. If the Maven Version Decorator is not enabled, a project will only list it’s name and relative path in the PackageExplorer as shown in Figure 5.5, “Package Explorer without Maven Version Decorator”:

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Figure 5.5. Package Explorer without Maven Version Decorator

Upon enabling the Maven Version Decorator, the project name will include the current project version as shown in Figure 5.6,“Package Explorer with Maven Version Decorator Enabled”:

Figure 5.6. Package Explorer with Maven Version Decorator Enabled

This is a helpful feature that provides the project version at a glance instead of being required to open the POM to locate the versionelement.

Chapter 6. Working with Maven Repositories6.1. Working with Maven Repositories

m2eclipse also provides some tools to make working with Maven repositories a bit easier. These tools provide functionality for:

• Searching for Artifacts

• Searching for Java classes

• Indexing Maven repositories

6.2. Searching For Maven Artifacts and Java classes

m2eclipse adds a couple of items to the Eclipse Navigation menu that make searching for Maven Artifacts and Java classes easywork. Each option is available by clicking on the Navigate menu as shown in Figure 6.1, “Searching for Artifacts and Classes”:

Figure 6.1. Searching for Artifacts and Classes

Notice the available options in Figure 6.1, “Searching for Artifacts and Classes” under the Eclipse Navigate menu named OpenMaven POM and Open Type from Maven. The Open Maven POM option allows you to search the Maven repository for a givenPOM as shown in Figure 6.2, “Searching for a POM”:

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Figure 6.2. Searching for a POM

Upon selecting an artifact and clicking OK, the POM for that artifact is opened in Eclipse for browsing or editing. This is handywhen you need to take a quick look at the POM for a given artifact.

The second m2eclipse option in the Navigate menu is named Open Type from Maven. This feature allows you to search for a Javaclass by name in a remote repository. Upon opening this dialog, simply type ‘factorybean’ and you’ll see many classes with the nameFactoryBean in them as shown in Figure 6.3, “Searching the Repository for a Class”:

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Figure 6.3. Searching the Repository for a Class

This is a big time saving feature because it means that manually searching through artifacts in a Maven repository for a particularclass is a thing of the past. If you need to use a specific class, just fire up Eclipse, go to the Navigate menu and search for the class.m2eclipse will show you the list of artifacts in which it appears.

6.3. Indexing Maven RepositoriesThe Maven Indexes View allows you to manually navigate to POMs in a remote repository and open them in Eclipse. To see thisView, go to View, Show View, Other, type the word "maven" into the search box and you should see a view named Maven Indexesas shown in Figure 6.4, “Show Maven Indexes View”:

Figure 6.4. Show Maven Indexes View

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Select this View and click OK. This will show the Maven Indexes View as shown in Figure 6.5, “Maven Indexes View”:

Figure 6.5. Maven Indexes View

Additionally, Figure 6.6, “Locating a POM from the Indexes View” shows the Maven Indexes View after manually navigating tolocate a POM:

Figure 6.6. Locating a POM from the Indexes View

After finding the apache-camel artifact, double-clicking on it will open it up in Eclipse for browsing or editing.

These features make working with remote repositories from inside of Eclipse so much easier and faster. After all the hours you mayhave spent doing these types of tasks by manually over the last few years - visiting repositories through a web browser, downloadingartifacts and grepping through them for classes and POMs - you'll find that m2eclipse is a welcome change for the better.

6.4. Browsing and Manipulating Maven RepositoriesThe m2eclipse plugin allows you to browse and manipulate repository indexes. Using the Maven Repository view in m2eclipse youcan:

• Browse your Local Maven repository

• Browse global repositories such as the Central Maven repository

• Browse a repository which captures artifacts generated by Maven projects in your Eclipse workspace

• Rebuild a Nexus Index from scratch

• Update a Nexus Index with incremental changes

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• Modify the scope of repository indexing with a "minimal" or "full" index

• Disable Indexing for a repository

• Materialize a Maven project from information stored in a POM

6.4.1. Opening the Maven Repository View

To browse Maven repositories and to manipulate repository indexes open the Maven Repositories view by selecting Windows, ShowView, Other... as shown in Figure 6.7, “Opening a View in Eclipse”.

Figure 6.7. Opening a View in Eclipse

Once you select Other... Eclipse will display a dialog containing all available views. Select the Maven Repositories view under theMaven folder in the Show View dialog as shown in Figure 6.8, “Selecting the Maven Repositories View in the Show View Dialog”.

Figure 6.8. Selecting the Maven Repositories View in the Show View Dialog

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Once you have selected Maven Repositories and clicked on the OK button, Eclipse will then load the Maven Repositories view.This view contains three folders:

Local RepositoriesThis folder contains your local Maven repository which is stored in ~/.m2/repository by default. It also contains a repositorythat represents the Maven projects contained in your Eclipse workspace.

Global RepositoriesThis folder contains any global Maven repositories that are referenced by all Maven projects. This folder contains the CentralMaven repository under the repository identifier of "central". It will also contain mirrors that have been configured in yourMaven Settings (~/.m2/settings.xml).

Project RepositoriesThis folder contains repositories which are defined by your projects. These repositories are present either in your project'spom.xml file or in an active Maven Profile.

6.4.2. Browsing Global Repositories

If you have been using Maven, you are familiar with the Central Maven repository. This is default repository from which Mavenwill retrieve dependencies and other artifacts needed during a build. If you expand the central repository, you will be able to browsethe contents of the repository and double click on specific artifacts. Double-clicking on one of the artifacts shown in Figure 6.9,“Browsing a Global Repository” will load that artifact's POM in the Form-based POM Editor.

Figure 6.9. Browsing a Global Repository

In addition to loading an artifact's POM in the Form-based POM Editor, you can also right click on a artifact and choose MaterializeProject. If the POM for a particular artifact contains valid SCM information, m2eclipse can "materialize" the project from sourcecontrol into your workspace.

6.4.3. Browsing Your Workspace Repository

m2eclipse maintains an index of artifacts generated by your Eclipse workspace. This "workspace" repository is shown in Figure 6.10,“Browsing the m2eclipse Workspace Repository” under the Local Repository folder. If you expand this folder, you will see artifactsthat correspond to your workspace project as shown in Figure 6.10, “Browsing the m2eclipse Workspace Repository”.

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Figure 6.10. Browsing the m2eclipse Workspace Repository

6.4.4. Browsing a Project Repository

The Maven Repositories view is also intelligent enough to keep track of any repositories that have been added to your project viayour Maven Settings, an active Maven Profile, or that have been added directly to a project's POM. To demonstrate this feature, add arepository element to a pom.xml, by loading the Form-based POM Editor and clicking on the Repositories tab. Click on the "Create..."button and add a new repository with the following values as shown in Figure 6.11, “Adding a Repository to a Project's POM”.

• Repository Identifier: flexmojos

• Repository Name: Flexmojos Repository

• URL: http://repository.sonatype.org/content/groups/flexgroup/

Note

You will only see the Repositories tab in your Form-based POM Editor, if you have set your Maven preferences to"Show advanced tabs in the POM Editor" under Eclipse, Preferences..., Maven, POM Editor.

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Figure 6.11. Adding a Repository to a Project's POM

Save the POM and open the pom.xml tab in the POM Editor. The project's pom.xml should contain the repositories element shownin Figure 6.12, “Project POM with a Custom Repository”.

Figure 6.12. Project POM with a Custom Repository

Now that the pom.xml contains a custom repository, click on the refresh icon shown in the upper right-hand of Figure 6.13,“Browsing a Project Repository”. The refresh icon looks like two opposing yellow arrows, and clicking this icon will cause theMaven Repositories view to refresh the list of repositories from the selected project and your configured Maven settings.

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Figure 6.13. Browsing a Project Repository

Once you have added a project repository and clicked on the refresh icon in the Maven Respositories view, you will be able to viewthe project-specific repository and manipulate the repository index for this project-specific repository.

6.4.5. Browsing Your Local Repository

The Maven Repostitories view allows you to browse and manipulate your local Maven repository index. m2eclipse maintains anindex for the contents of your local repository, you can use this interface to browse artifacts that have been loaded into your localrepository as shown in Figure 6.14, “Browsing Your Local Maven Repository”.

Figure 6.14. Browsing Your Local Maven Repository

6.4.6. Manipulating a Repository Index

Every repository that m2eclipse uses is indexed by the Nexus Indexer. If m2eclipse is using a remote repository, it will download aNexus index from the remote repository. If m2eclipse is managing a local repository (local or workspace) it will use the open sourceNexus indexer to create and maintain a local index. This index is what allows you to quickly search for and locate dependencies byartifactId, groupId, version, or classname. You can manipulate the index that is associated with a Maven repository by right-clickingon a repository in the Maven Repositories view and selecting one of the following actions:

Update IndexThis will update the index by running an incremental update or by downloading and index from a remote repository.

Rebiuld IndexThis will rebuild an index for a local repository by iterating through the contents of a repository and recreating a Nexus indexfrom scratch. This can be a useful tool if there is another process outside of Eclipse that is going to be modifying a localMaven repository.

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Disable IndexChoosing this option causes m2eclipse to skip index generation for a repository. This can come in handy if you have a seriesof repositories which you do not want to include in artifact searches. If your organization maintains a number of specialized,segregated repositories that hold snapshots, you may not want to include these artifacts in simple searches for artifacts thatcontain a particular identifier or class.

Figure 6.15. Updating a Repository Index

Figure 6.15, “Updating a Repository Index” shows two indexing options that control the scope of a particular Nexus index:

Enable Min IndexConfigures the Nexus Indexer to maintain a minimal index that doesn't contain information about class names.

Enable Full IndexConfigures the Nexus Indexer to maintain a full Index that includes the class names contained within each artifact.

Chapter 7. Using m2eclipse7.1.1. Adding and Updating Dependencies and Plugins

Let’s say we’d like to add a dependency or a plugin to the camel-core POM. For the sake of demonstration, we're going to addcommons-lang as a dependency. (Please note that the functionality for adding a dependency or a plugin is exactly the same so we’lldemonstrate it by adding a dependency.)

m2eclipse offers two options for adding dependencies to a project. The first option is by manually editing the POM file to type in theXML to add the dependency. The downside to manually editing the POM file to add a dependency is that you must already knowthe information about the artifact, or use the features discussed in the next section to manually locate the artifact information in therepository indexes. The upside is that after manually adding the dependency and saving the POM, the project’s Maven Dependenciescontainer will be automatically updated to include the new dependency. Figure 7.1, “Manually Adding a Dependency to the Project'sPOM” shows how I added a dependency for commons-lang to the camel-console POM and the Maven Dependencies containerwas automatically updated to included it:

Figure 7.1. Manually Adding a Dependency to the Project's POM

Manually adding a dependency works well but requires more work than the second approach. Upon manually adding the dependencyelement to the POM, the Eclipse progress in the lower right-hand corner of the Eclipse workbench reflects the action as shown inFigure 7.2, “Updating Maven Dependencies”:

Figure 7.2. Updating Maven Dependencies

The second option for adding a dependency is much easier because you don’t have to know any information about the artifact otherthan its groupId. Figure 7.3, “Searching for a Dependency” shows this functionality:

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Figure 7.3. Searching for a Dependency

By simply entering a groupId into the query field, m2eclipse queries the repository indexes and even shows a version of the artifactthat is currently in my local Maven repository. This option is preferred because it is such a tremendous time saver. With m2eclipse,you no longer need to hunt through the central Maven repository for an artifact version.

7.1.2. Downloading Source

If the central Maven repository contains a source artifact for a particular project, you can download the source from the repositoryand expose it to the Eclipse environment. When you are trying to debug a complex issue in Eclipse, nothing can be easier than beingable to right click on a third-party dependency and drill into the code in the Eclipse debugger. Select this option, and m2eclipse willattempt to download the source artifact from the Maven repository. If it is unable to retrieve this source artifact, you should ask themaintainers of the project in question to upload the appropriate Maven source bundle to the central Maven repository.

7.1.3. Opening Project Pages

A Maven POM contains some valuable URLs which a developer may need to consult. These are the project's web page, the URL forthe source code repository, a URL for a continuous integration system like Hudson, and a URL for an issue tracker. If these URLsare present in a project's POM, m2eclipse will open these project pages in a browser.

7.1.4. Resolving Dependencies

You can configure a project to resolve dependencies from a workspace. This has the effect of altering the way that Maven locatesdependency artifacts. If a project is configured to resolve dependencies from the workspace, these artifacts do not need to be presentin your local repository. Assume that project-a and project-b are both in the same Eclipse workspace, and that project-a dependson project-b. If workspace resolution is disabled, the m2eclipse Maven build for project-a will only succeed if project-b'sartifact is present in the local repository. If workspace resolution is enabled, m2eclipse will resolve the dependency via the Eclipseworkspace. In other words, when workspace resolution is enabled, project's don't have to be installed in the local repository to relateto one another.

You can also disable dependency management. This has the effect of telling m2eclipse to stop trying to manage your project'sclasspath, and it will remove the Maven Dependencies classpath container from your project. If you do this, you are essentially onyour own when it comes to managing your project's classpath.

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7.2. Analyzing Project Dependencies in m2eclipseThe latest release of m2eclipse contains a POM editor which provides some dependency analysis tools. These tools promise tochange the way people maintain and monitor a project's transitive dependencies. One of the main attractions to Maven is the factthat it manages a project's dependencies. If you are writing an application which depends on the Spring Framework's Hibernate3integration, all you need to do is depend on the spring-hibernate3 artifact from the Central Maven Repository. Maven then readsthis artifact's POM and adds all of the necessary transitive dependencies. While this is a great feature that attracts people to usingMaven in the first place, it can often become confusing with a project starts to depend on tens of dependencies, each with tens oftransitive dependencies.

Problems start to happen when you depend on a project with a poorly crafted POM which fails to flag dependencies as optional,or when you start encountering conflicts between transitive dependencies. If one of your requirements is to exclude a dependencylike commons-logging or the servlet-api, or if you need to find out why a certain dependency is showing up under a specificscope you will frequently need to invoke the dependency:tree and dependency:resolve goals from the command-line to trackdown the offending transitive dependencies.

This is where the POM editor in m2eclipse comes in handy. If you open a project with many dependencies, you can open theDependency Tree tab and see a two-column display of dependencies as shown in Figure 7.4, “Dependency Tree Tab of the POMEditor”. The left-side of the panel displays a tree of dependencies. The first level of the tree consists of direct dependencies from yourproject, and each subsequent level lists the dependencies of each dependency. The left-hand side is a great way to figure out how aspecific dependency made its way into your project's resolved dependencies. The right-hand side of this panel displays the resolveddependencies. This is the list of effective dependencies after all conflicts and scopes have been applied, and it is the effective list ofdependencies that your project will use for compilation, testing, and packaging.

Figure 7.4. Dependency Tree Tab of the POM Editor

The feature which makes the Dependency Tree tab so valuable is that it can be used as an investigative tool to figure out how aspecific dependency made it into the list of resolved dependencies. Searching and filtering functionality available in the editor makesit really easy to search and browse trough the project dependencies. You can use “Search” entry field from the editor tool-bar and“Sort” and “Filter” actions from “Dependency Hierarchy” and “Resolved Dependencies” sections to navigate trough dependencies.Figure 7.5, “Locating Dependencies in the Dependency Tree” shows what happens when you click on commons-logging in the"Resolved Dependencies" list. When filtering is enabled in “Dependencies Hierarchy” section, clicking on a resolved dependencyfilters the hierarchy on the left-hand side of the panel to show all of the node which contributed to the resolved dependency. If youare trying to get rid of a resolved dependency, you can use this tool to find out what dependencies (and what transitive dependencies)

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are contributing the artifact to your resolved dependencies. In other words, if you are trying to get rid of something like commons-logging from your dependency set, the Dependency Tree tab is the tool you will likely want to use.

Figure 7.5. Locating Dependencies in the Dependency Tree

m2eclipse also provides you with the ability to view your project's dependencies as a graph. Figure 7.6, “Viewing the Dependenciesof a Project as a Graph” shows the dependencies of idiom-core. The top-most box is the idiom-core project and the otherdependencies are shown below it. Direct dependencies are linked from the top box and the transitive dependencies are linked fromthose. You can select a specific node in the graph to highlight the linked dependencies, or you can use the Search field at the topof the page to find matching nodes.

Note that “open folder” icon on each graph node indicates that the corresponding artifact is present in the Eclipse workspace and“jar” icon indicates that the node's artifact is referenced from the Maven repository.

Figure 7.6. Viewing the Dependencies of a Project as a Graph

The graph presentation can be changed by right clicking in the editor. You can choose to show artifact ids, group ids, versions,scopes, or if you want to wrap node text or show icons. Figure 7.7, “Radial Layout of Dependency Graph” shows the same graphfrom Figure 7.6, “Viewing the Dependencies of a Project as a Graph” with a radial layout.

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Figure 7.7. Radial Layout of Dependency Graph

Chapter 8. Using m2eclipse8.1. Working with Maven ProjectsThe m2eclipse plugin also provides a set of features for working with Maven projects once they are inside of Eclipse. There aremany features that ease the ability to use Maven in Eclipse so let’s dive right into them. In the previous section, I materialized aMaven project and selected a subproject from the Apache Camel project named camel-core. We’ll use that project to demonstratethese features.

By right-clicking on the camel-core project, and selecting the Maven menu item, you can see the available Maven features. Figure 8.1,“Available Maven Features” shows a screenshot of this:

Figure 8.1. Available Maven Features

Notice in Figure 8.1, “Available Maven Features” the available Maven features for the camel-core project, including:

• Adding dependencies and plugins

• Updating dependencies, snapshots and source folders

• Creating a Maven module

• Downloading the source

• Opening Project URLs such as the Project Web Page, Issue Tracker, Source Control, and Continuous Integration tool.

• Enabling/Disabling workspace resolution, nested Maven modules and dependency management

These features are also big time savers so let’s review them briefly.

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8.1.1. Downloading Source

If the central Maven repository contains a source artifact for a particular project, you can download the source from the repositoryand expose it to the Eclipse environment. When you are trying to debug a complex issue in Eclipse, nothing can be easier than beingable to right click on a third-party dependency and drill into the code in the Eclipse debugger. Select this option, and m2eclipse willattempt to download the source artifact from the Maven repository. If it is unable to retrieve this source artifact, you should ask themaintainers of the project in question to upload the appropriate Maven source bundle to the central Maven repository.

8.1.2. Opening Project Pages

A Maven POM contains some valuable URLs which a developer may need to consult. These are the project's web page, the URL forthe source code repository, a URL for a continuous integration system like Hudson, and a URL for an issue tracker. If these URLsare present in a project's POM, m2eclipse will open these project pages in a browser.

8.1.3. Resolving Dependencies

You can configure a project to resolve dependencies from a workspace. This has the effect of altering the way that Maven locatesdependency artifacts. If a project is configured to resolve dependencies from the workspace, these artifacts do not need to be presentin your local repository. Assume that project-a and project-b are both in the same Eclipse workspace, and that project-a dependson project-b. If workspace resolution is disabled, the m2eclipse Maven build for project-a will only succeed if project-b'sartifact is present in the local repository. If workspace resolution is enabled, m2eclipse will resolve the dependency via the Eclipseworkspace. In other words, when workspace resolution is enabled, project's don't have to be installed in the local repository to relateto one another.

You can also disable dependency management. This has the effect of telling m2eclipse to stop trying to manage your project'sclasspath, and it will remove the Maven Dependencies classpath container from your project. If you do this, you are essentially onyour own when it comes to managing your project's classpath.

8.2. Using the Form-based POM Editor

The latest release of the m2eclipse plugin has a form-based POM editor which allows you to edit every part of a project's pom.xmlwith an easy-to-use GUI interface. To open the POM Editor, click on a project's pom.xml file. If you've customized the editors fora pom.xml file, and the POM Editor is not the default editor, you may need to right-click on the file and choose "Open With... /Maven POM Editor". The POM Editor will then display the Overview tab as shown in Figure 8.2, “Overview Tab of POM Editorfor idiom-core”.

Note

The Form-based POM Editor is only available if you selected the POM Editor component when you installed them2eclipse Eclipse plugin. For more information about installing the m2eclipse plugin, see Section 2.3.1, “Installingm2eclipse Core Components”.

One common complaint about Maven is that it forces a developer to confront large and often overwhelming XML documents in ahighly complex multi-module project build. While the authors of this book believe this is a small price to pay for the flexibility ofa tool like Maven, the graphical POM editor is a tool that makes it possible for people to use Maven without ever having to knowabout the XML structure behind a Maven POM.

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Figure 8.2. Overview Tab of POM Editor for idiom-core

The project shown in Figure 8.2, “Overview Tab of POM Editor for idiom-core” is a project with an artifactId of of idiom-core. You'll notice that most of the fields in this idiom-core project are blank. There is no groupId or version and there is noSCM information supplied in the POM editor. This is due to the fact that idiom-core inherits most of this information from a parentproject named idiom. If we open the pom.xml for the parent project in the POM Editor we would see the Overview tab shown inFigure 8.3, “Overview Tab of POM Editor for idiom Parent Project”.

That “open folder” icon on the various list entries throughout the POM editor indicate that the corresponding entry is present in theEclipse workspace and “jar” icon indicates artifacts which are referenced from the Maven repository. You can double-click on thoseentries in order to open its POM in the POM editor. This works for modules, dependencies, plugins and other elements that havecorresponding Maven artifacts. Underlined labels in several POM editor sections represent hyperlinks which can be used to openthe POM editor for corresponding Maven artifact.

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Figure 8.3. Overview Tab of POM Editor for idiom Parent Project

In this parent POM, we see that the groupId and version are defined and that the parent POM supplies much of the informationwhich was missing in the idiom-core project. The POM editor is going to show you the contents of the POM that you are editing,and it will not show you any of the inherited values. If you wanted to look at the idiom-core project's effective POM in the POMeditor, you can use “Show Effective POM” action from the tool-bar in the upper right-hand corner of the POM editor, which showsa left bracket and an equals sign on a page with a blue M. It will load the effective POM for idiom-code in the POM Editor asshown in Figure 8.4, “Effective POM for idiom-core”.

Figure 8.4. Effective POM for idiom-core

This effective view of the POM merges the idiom-core POM with the ancestor POMs (the parent, the grandparent, etc.), similarlyto “mvn help:effective-pom” command and displays the POM editor with the effective values. Because the POM editor is displaya composite view of many different merged POMs, this effective POM Editor is read-only, and you will not be able to update anyof the fields in this effective POM view.

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If you were looking at the POM editor for the idiom-core project as shown in Figure 8.2, “Overview Tab of POM Editor for idiom-core”, you can also navigate to the parent POM using, ”Open Parent POM” action from the POM editor tool-bar in the upper right-hand of the POM editor.

The POM editor shows a number of showing various information from the POM. The final tab exposes the pom.xml as an XMLdocument. There is a dependencies tab shown in Figure 8.5, “Dependencies Tab of the POM Editor” which exposes an easy-to-useinterface for adding and editing dependencies to your project, as well as editing the dependencyManagement section of the POM.This dependency management screen is also integrated with the artifact searching facilities in the m2eclipse plugin. You can useactions from the editor sections, as well as Ctrl-Space typing assistance for the fields in “Dependency Details” section.

If you need to know more about one of the artifacts, you can use “Open Web Page” action from “Dependency Details” section tool-bar to check the project web page.

Figure 8.5. Dependencies Tab of the POM Editor

The build tab shown in Figure 8.6, “Build Tab of the POM Editor” provides access to the contents of the build element. From thistab you can customize source directories, add extensions, change the default goal name, and add resources directories.

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Figure 8.6. Build Tab of the POM Editor

We only showed a small subset of the POM editor. If you are interested in seeing the rest of the tabs, please download and installthe m2eclipse plugin.

8.3. Summarym2eclipse is more than just a simple plugin which adds Maven support to Eclipse, it is a comprehensive integration that will makeeverything from creating new projects to locating third-party dependencies orders of magnitude easier. m2eclipse is the first steptoward an IDE that is aware of the rich semantic treasure that is the central Maven repository. As more people come to use m2eclipse,more projects are going to be releasing Maven Archetypes, and more projects are going to see value in publishing source artifactsto the Maven repository. If you've tried to use Eclipse and Maven together without a tool that can comprehend the hierarchicalproject relationships that are central to any multi-module Maven project, you will know that the ability to work with nested projectsis essential to smooth integration between the Eclipse IDE and Maven.

Part II. Maven Studio for EclipseThe second portion of this book deals with Maven Studio for Eclipse.

Chapter 9. Introduction to Maven Studio forEclipse9.1. IntroductionMaven Studio for Eclipse currently provides Developer Onboarding, a feature fully introduced and defined in Section 9.2, “DeveloperOnboarding”. For more information about Maven Studio for Eclipse, please contact info@sonatype.com1.

9.2. Developer OnboardingDeveloper Onboarding can be defined as the process of bringing a developer "onboard" a particular development project. This processusually encompasses setting up the tools used during development - an Integrated Development Environments, compilers, and othertools used to design, write, test, debug, and deploy code. This section describes some of the challenges involved in DeveloperOnboarding, and provides some context for the Developer Onboarding feature now available in Maven Studio for Eclipse.

9.2.1. The Cost of New Developer Onboarding

On average, it typically takes a new developer five days before they can start contributing to a project. During this 5-day period, adeveloper will complete the tasks described below and illustrated in Figure 9.1, “A Representative 5-Day, Manual Onboarding”:

Day 1 Workstation SetupSetup a workstation, install baseline requirements such as a Java Development Kit and other languages or fundamentalframeworks.

Day 2 Downloading ComponentsDownload all of the components required for a development environment, this often includes components like:

• Source Control tools (Subversion, Git, Clearcase, or CVS)

• Integrated Development Environments (Eclipse IDE)

• Automated Testing Tools (Selenium)

• Application Servers / Containers (Websphere, Jetty, Tomcat)

• Build Tools (Maven, Ant)

• Databases (Oracle, MySQL, SQL Server)

• Scripting Languages (Ruby, Python, Perl)

• General Utilities (cygwin, emacs, other utilities)

The best-case scenario is an organization which maintains a detailed list of software components required in a developmentenvironment. In most organizations this information isn't firmly fixed in time as different developers set up environments asthey are introduced to a project. New programmers will often notice a slight variation in the versions of components used byother programmers in the same group. Example: a senior developer who has been on the team for years might still use Eclipse3.4, while newer developers might just download the latest version of Eclipse 3.5.1.

Day 2 Self-directed LearningDevelopers not directly familiar with tools like Maven will need to learn how to install and configure these tools. Mostnew developers spend at least half a day familiarizing themselves with the installation and configuration process for newdevelopment infrastructure.

1 mailto:info@sonatype.com

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Day 3 Installing SoftwareOnce all of the required software has been downloaded, it must be installed and configured. Eclipse must be installed andconfigured, a local testing database must be configured, the IDE settings must be customized to account for specific standardsused by the organization.

Day 3 Ad-hoc TrainingAfter setting up and environment, a developer will usually require the assistance of other members of the development team.Ad-hoc training sessions will involve other developers communicating standards and software: "Have you used JUnit before?This is how we run a unit test."

Day 4 Source CodeIt is just at Day 4 that a developer starts to think about accessing source code. More dicussions with members of the samegroup about source code are usually accompanied by an overview of the various source control systems and structure of thevarious groups. Checking out source code is as much about learning about the organizational structure of a code base as it isabout learning how that code maps to project groups. Who is responsible for various components, how is the source checkedout of source control, and how often is it updated.

Day 4 Build SystemOnce the code is properly checked out and imported into your IDE, a developer will need to build an entire system. If theorganization has already standardized on a tool like Apache Maven, this could be as simple as typing in "mvn clean install"at the command prompt. Most organizations require some level of customization for a build to work properly. Whether thismeans that a developer needs to fully understand a custom Ant build or just find out how to configure Maven settings toconnect to a Nexus repository, there is usually some work involved in figuring out how the build works and how it shouldbe configured properly.

Day 5 Configuring Development EnvironmentOnce a developer can build the code, the next step is to configure a local development environment. If a developer is working onan enterprise application, this may involve setting up a local instance of a database and populating that database with test data.

Day 5 Integrating 3rd Party ProjectsIf an enterprise application depends on 3rd-party open source projects, a developer will often checkout relevant source codefrom open source projects and configure them alongside the development environment for internal code.

Introduction HR Tour Technical Overview

Team Meeting Workstation Setup

Downloading Components Self-directed Learning

Installing Software (Eclipse, Subversion) Ad-hoc Training

Checking Out Source Code Learning Build System / Customizing Settings

Configuring Development Environment Integrating 3rd Party Projects Productive

Day 1

Day 2

Day 3

Day 4

Day 5

Figure 9.1. A Representative 5-Day, Manual Onboarding

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9.2.2. Onboarding with Maven Studio for Eclipse: Productive on Day One

With Maven Studio for Eclipse, a build engineer can capture all of the components required for a development environment in anMSE Codebase. This MSE Codebase is then published to Nexus Team edition and is downloaded by a developer in a process called"Materialization". When a developer materializes an MSE Codebase, a component called the MSE Installer downloads an XMLdescriptor which captures all of the configuration parameters for a completely customized build environment.

Figure 9.2, “Minimizing Onboarding Time with Maven Studio for Eclipse” shows the process from Figure 9.1, “A Representative5-Day, Manual Onboarding” condensed into a single day. A developer's first day on the job is still characterized by introductions,tours, and meetings, but instead of relegating a developer to a week of manual installation and configuration tasks, a developer simplyclicks on a link to materialize an MSE Codebase. An MSE Codebase can be materialized in a few minutes, and once this processis done, a new developer can be productive on Day One.

Introduction HR Tour Technical Overview

Team Meeting

MSEOnboarding ProductiveDay 1

Figure 9.2. Minimizing Onboarding Time with Maven Studio for Eclipse

The ramifications of this easy setup process are more than just time saved and efficiencies gained. When it only takes a new developera few minutes to get his or her workstation setup, they can take more time in the first days to learn about projects and architecture.They can start to engage a group socially, participating in development discussions and decisions instead of disappearing into a caveto install software.

This new ability to get prouctive quickly also changes the way in which developers are added to a project. When you know it will onlytake a few minutes to install a development environment, checkout all required source code, and configure a build, you won't haveto build in a week of downtime into your schedule for new developers. If your project needs the help, you can hire a new developerto make focused changes without having to sacrifice five days of time to inefficient manual setup.

Maven Studio for Eclipse makes your organization more agile, more efficient. Increased efficiencies do more than save time andresources. They change the dynamics of the group and make it possible to focus more on your application's code and less on thetools required to build it.

9.2.3. Managing Developer Workspace Complexity

Developers spend most of their time connecting components within a development environment to one another. As open sourcesoftware tools and components have created a wealth of choices, these tools have also increased the cognitive burden on softwaredevelopers. Gone are the days when a developer could simply install Java, Eclipse, and Maven and just start to code. In today'ssoftware development environment, a developer needs to not only configure an IDE, she needs to connect that IDE to a collectionof infrastructure resources like JIRA and Confluence, configure the system to interact with source control, and install any numberof supporting components.

As most developers only configure a workstation once or twice a year, the true complexity is always somewhat surprising. Developersdon't realize exactly how much time is wasted on workstation setup until they've wasted an entire day downloading and installingthe various software components involved in an environment. This process is not unlike process most Java developer used to useto obtain dependencies for a Java project.

Before the arrival of Maven, a software developer had to manually download and configure a set of libraries, a set of dependencies.Maven Studio for Eclipse takes one of the central ideas of Maven, the idea that you can describe your project and let Maven takecare of downloading components from a central repository, and it applies this concept to your development environment. Instead ofasking your developers to download, configure, and connect an increasing number of components. Use Maven Studio, capture yourdevelopment environment in a descriptive codebase, and let Maven Studio for Eclipse take care of the details.

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MavenStudio

+=

Figure 9.3. Consolidating Complexity into Eclipse IDE

9.3. Managing Change in Development Environments

When you use Maven Studio for Eclipse Developer Onboarding, and you standard your entire development team's environment onmanaged Eclipse codebases, you start to decrease the amount of time, the amount of investment necessary to update and maintainyour development environment. Once you've created a system that allows you to redeploy a new development environment overhundreds of workstations in a few hours, you've implemented low-risk, or "disposable" development environments. The cost tochange your developer's environments is small enough that you can start making changes without having to worry about the logisticsof such a change.

To illustrate the benefits of low-risk, or "disposable" development environments consider the ongoing invest of time and effort to keepa development environment up to date. The follow two examples illustrate the differences between using high-risk, high-investmentdevelopment environments, and low-risk, "disposable" development environments.

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9.3.1. The Common Scenario: Upgrading Development Infrastructure

Consider a average sized workgroup of 20 developers and 5 project managers. This team of 20 developers is split up into 4 teams offive engineers, and each team works with a project manager to set direction and track progress. The product development lifecycle inthis particular organization is twelve months. From initial product design to testing to implementation and lastly final delivery takes,on average about twelve months start to finish. Let's also assume that the entire team uses the same development environment, thesame testing infrastructure, and a common approach to tools, releases, and source control.

At the start of a project development cycle, senior developers from each team usually meet to decide upon changes to the developmenttool stack. Questions like: What version of Eclipse are we standardizing on? What is the structure of our source code repository?What tools do we need to standardize on for testing? All of these questions are answered at the beginning of the project, and whiledevelopers and project managers are working on architecture issues and other plans, there is a build engineer or an architect who istasked with documenting a standard set of tools and procedures for development.

This tools selection and standardization process usually takes two weeks to complete. While we are not dealing with new employees,very often when a new development stack is introduced, developers and managers need to recalibrate knowledge of tools, retrainthemselves on the latest versions of build systems and IDEs, maybe the organization also uses this time period of refresh engineer'slaptops. Getting a new laptop after two years of working can often introduce as much downtime in project schedules as hiring anew employee.

The point here is that technology management understands that there is some downtime at the start of a project to allow the seniortechnical talent to introduce newer approaches technologies into the mix. This is commonly accepted practice, and it makes senseto introduce risky changes at the beginning of a product lifecycle when there is enough time to mitigate any unexpected problemsthat might be introduced by such a change.

9.3.2. Disadvantages of a High-Risk Development Environment

Assume that it takes about two weeks to deliver change to the development environment. A new Eclipse-based plugin needs to beconfigured, tested, and delivered to every developer workstations, or source control locations needs to be refactored or split. Thistwo weeks is not the time it takes for any one developer to implement a change. This two week period is the time it takes for buildengineers to introduce the change, train developers, and then migrate individual developer workstations over to a new developmentenvironment. In this scenario, developers manually build workstations from a set of instructions, and each developer also has thepotential to install different versions on a workstation. The two week period is the length of time it takes for most developers toconvert and for every developer to work out any issues which may arise during an environment upgrade.

Figure 9.4, “High-risk Development Environments Discourage Change within Constrained Development Cycles” illustrates the end-result of having such a high-risk approach to development environments. Because the process of deploying change to a developmentenvironment take two weeks to fully implement, technical managers are going to be very careful about introducing any change intothe environment in the middle of an active product development cycle. If a new version of Eclipse is introduced which improvesperformance, or if a new version of Maven is made available that enables greater flexibility, managers are not likely to approveany changes.

The following, fictional dialog captures the reality of a development group with a manual, high-risk strategy for testing and deployingchanges to development infrastructure:

Build Engineer: "They just released a new version of Maven to address some of the issues we are having withthe Surefire plugin."

Manager: "How long is it going to take to test and deploy this fix to 100 developers?"

Build Engineer: "One week of testing and about a week to deploy the changes to every team. We have to wait forpeople to have enough time available to follow our instructions."

Manager: "If it isn't critical, I'd rather wait until we've completed this cycle to implement this change. It doesn'tseem worth it given the risk that our timelines will be affected."

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High-risk Changes to Dev Environment

(2 weeks)

Development Cycle(12 months)

Start

Figure 9.4. High-risk Development Environments Discourage Change within Constrained Development Cycles

If you work in one of these environments you'll recognize this situation. Managers are understandably risk-averse because they knowthat there is no automatic method for deploying changes to development environments. Developers are also risk averse because everytime the build engineers come up with a new idea they lose a substantial amount of time following a loosely documented, ad-hocprocess for running manual updates. In this scenario, the build engineer is often identified as the enemy of project stability and theteam resists changes to the development environment.

9.3.3. Advantages of a Low-risk Development Environment

When an organization has standardized on low-risk, disposable development environments using Maven Studio for Eclipse, it takeslittle or no time to redeploy changes across all developer workstations. If the department needs to upgrade from Eclipse 3.5.1 toEclipse 3.6.0 or upgrade to a newer version of the m2eclipse plugin, this change can be executed in a matter of hours. A build engineercan test a change to a development environment, publish a codebase to Nexus Team Edition and then send an email to hundredsof developers instructing them to materialize the latest codebase. In minutes, every engineer in the group can materialize the samedevelopment environment. Most importantly, if the newly published MSE Codebase has a problem or an issue, developers can rullback to a previous version of the published Codebase and continue developing.

This ability to quickly deploy a development environment doesn't just save time, it alters the dynamic between the build engineer andthe project planners. If the build engineer proposes a change to the development environment which involves an upgrade to Eclipseor Maven, the build engineer can make the case that this change is low-risk. It can be implemented in a single day and deployed inminutes to every developer. If the proposed change introduces errors, developers can rollback.

Figure 9.5, “Low-risk Development Environments Enable Greater Flexibility within Constrained Development Cycles” illustratesthe new dynamic introduced by low-risk changes to development environment. With Maven Studio for Eclipse, it doesn't take twoweeks to convince your developers to upgrade to a new development environment, and project managers can no longer object to asimple, repeatable process with a guaranteed fallback plan.

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Low-risk Changes to Dev Environment

(1 day)

Development Cycle(12 months)

Start

Figure 9.5. Low-risk Development Environments Enable Greater Flexibility within Constrained Development Cycles

Figure 9.5, “Low-risk Development Environments Enable Greater Flexibility within Constrained Development Cycles” shows a12-month product development lifecycle with a series of low-risk changes to the development environment. Instead of waiting toschedule high-risk project downtime for infrastructure changes, you can upgrade your development infrastructure whenever you needto. Development doesn't have to come to a complete halt when it only takes a few minutes to materialize a codebase. If a new versionof Eclipse or a critical tool from a vendor is updated, you will be able to quickly test and deploy this fix across your departmentwthout having to make the case to management to set aside time for the upgrade.

Maven Studio for Eclipse enables much greater flexibility within constrained development cycles because it makes developmentenvironment "disposable". You don't have to invest everyone's time in the installation and upgrade of development infrastructure; doin once, test it, publish, and everyone will have a standard environment immediately.

9.4. Consolidating Project FeedsDeveloping good software is a very social activity. For people not directly involved in a development effort, this is not immediatelyobvious. If you don't spend your time programming, you might just think developers are doing nothing more than staring at Eclipsetwelve hours a day and communicating with each other using terse, cryptic Subversion commit messages. In reality, good developersare constantly interacting on IRC, using Issue Trackers such as JIRA, having heated debates on mailing lists, and using other meansof communication. If your development group involves open source, developers working on open source are communicating to largegroups of volunteers over public channels such as Twitter and GitHub.

Maven Studio for Eclipse provides a mechanism for aggregating feeds for a Source Tree. You can use this mechanism as anopportunity to make sure that developers working on a particular system are following the right feeds. Think of feed support in theMSE product like having a project specific feedreader that you can configure, distribute, and update. In this industry, information isof primary importance and making sure that your developers are keeping up to date on the ever increasing number of technologiesthey need to know is important. With Maven Studio for Eclipse, you gain the ability to make sure that developers are paying attentionto the right pieces of information.

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9.4.1. Simple Scenario: Aggregating a Project's Feeds

If your team is tracking project progress using Atlassian's JIRA issue tracker, collaborating on documentation using Atlassian'sConfluence wiki, changing source code stored in Subversion, monitoring production systems using Nagios, tracking builds usingHudson, and dscussing strategy using services like Twitter, all of these channels create a constant stream of events and which helpdevelopers track activity.

Figure 9.6, “Aggregating a Single Project's Feeds” illustrates how Maven Studio for Eclipse Source Trees can be used to aggregatethis information into a simple project activity feed presented in the Eclipse IDE. Without Maven Studio for Eclipse, this aggregatedfeed is something a developer has to fetch himself. When a new piece of development infrastructure such as JIRA or Subversionis added to a project, a developer has to figure out how to integrate any available activity streams into his personal feed reader.Usually this means that every bit of development infrastructure involved in the development effort is configured to push automatedemails to developer.

While this strategy of constantly flooding each developer with activity emails accomplishes the job, it also ignores the fact that everypiece of development infrastructure provides support for common feed standards such as RSS and Atom. Maven Studio for Eclipseintegrates with these feed standards and it gives build engineers a standard mechanism to make sure that every developer is payingattention to the same set of valuable feeds. If you've installed a new source control system, or a new tool like Sonar which generates auseful RSS feed, just update the codebase, publish it to Nexus Team Edition, and tell your developers to materialize the latest versionof a codebase. In minutes, you can make sure that everyone is paying attention to the same activity stream within Eclipse.

ContinuousIntegration(Hudson)

IssueTracker(JIRA)

Wiki(Confluence)

SourceControl

(Subversion)

SocialMedia

(Twitter)

ProductionMonitoring

(Nagios)

MSE CodebaseSource Tree

Project ActivityTwitter: @Brian_Fox: The new production build is now available from Central Staging

SVN: Commit 423242 by jvanzyl: Updated the storage implementation to account for NoSQL

Nagios: Warning on app01: Disk utilization currently at 97%. Address problem immediately.

Hudson Build #423 Success: Triggered by SVN Commit 423242. 400 out of 400 tests passes.

...

Figure 9.6. Aggregating a Single Project's Feeds

9.4.2. Complex Scenarios: Mixed Open/Commercial Development

A increasingly common scenario in enteprise development is the hybrid open source/commercial development effort. Companieslarge and small are starting to build systems to expose an open source core or API to the public which relates to a commercialproduct or commercial extension. Sonatype's Nexus repository manager is just such a project. Nexus Open Source has a large, vibrantdevelopment community that includes many developers not directly employed by Sonatype. Nexus Professional has a smaller teamof programmers who are all directly employed by Sonatype.

Another common scenario is a company which develops a complex enterprise system which relies heavily on customized open sourcecomponents. Companies like Google develop large, proprietary codebases for cloud computing while making massive, continuedcontributions to the open source projects it depends on. In these scenarios, you may configure an MSE Codebase with two sourcetrees, one proprietary source tree pointing to your own, private source code repository, and another source tree pointing to a public,open-source repository.

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In the scenario of a mixed, open/commercial development effort, you can configure the Open Source source tree to track publiccomponents: public issue trackers, twitter accounts of the main contributors, public mailling lists, and you can configure theCommercial source tree to track private activity logs from internal issue trackers and source code control systems. Developers willthen see a unified view of project activity. They can keep up with the critical, open-source projects that the system depends on andthey can keep track of internal activity.

ContinuousIntegration(Hudson)

IssueTracker(JIRA)

Wiki(Confluence)

SourceControl

(Subversion)

SocialMedia

(Twitter)

ProductionMonitoring

(Nagios)

Open SourceSource Tree

Project ActivityTwitter: @Brian_Fox: The new production build is now available from Central Staging

SVN: Commit 423242 by jvanzyl: Updated the storage implementation to account for NoSQL

Nagios: Warning on app01: Disk utilization currently at 97%. Address problem immediately.

Hudson Build #423 Success: Triggered by SVN Commit 423242. 400 out of 400 tests passes.

Twitter: @SonatypeNexus: RSO is running Nexus Team Edition. See announcement: http://bit.ly/arznMT

...

SVN: Commit 233 by juven: Fixed bugs reported by Windows 64-bit users. Increased coverage.

Nagios: Warning on app01: Disk utilization currently at 97%. Address problem immediately.

Twitter: @SonatypeNexus: RSO is running Nexus Team Edition. See announcement: http://bit.ly/arznMT

ContinuousIntegration(Hudson)

IssueTracker(JIRA)

Wiki(Confluence)

SourceControl

(Subversion)

SocialMedia

(Twitter)

ProductionMonitoring

(Nagios)

CommercialSource Tree

Figure 9.7. Aggregating Multiple Project's Feeds

Chapter 10. Maven Studio for Eclipse Quickstart10.1. IntroductionMaven Studio for Eclipse (MSE) gives you the ability to capture common configuration and projects for your developers with theDeveloper Onboarding feature. Using the Developer Onboarding feature, you can very quickly configure and deliver a commonconfiguration across your entire enterprise.

Newly hired developers or developers just starting on a new project usually take days to setup and configure all of the moving partsthat go into an efficient development environment. With Developer Onboarding, a build engineer can capture all of the requirementsin an MSE Codebase and publish this Lineup to a simple, single-click solution which will download, install, and configure an EclipseIDE with all of the components necessary to be productive in minutes.

10.1.1. What is a Codebase?

A Codebase describes an entire development environment including both the configuration of Eclipse and the projects that are to bechecked out from source control. The Codebase contains two parts: A Lineup and one or more Source Trees as shown in Figure 10.1,“Maven Studio for Eclipse Codebase Contents”.

MSE Codebase

MSE Lineup

Eclipse Distribution

Eclipse Plugins/Components

Source Tree SCM Information

Project Information

Source Roots

Eclipse Preferences

Codebase Description/Icon

(one or more)

Figure 10.1. Maven Studio for Eclipse Codebase Contents

10.1.2. What is a Lineup?

A Lineup describes an Eclipse environment: the version of Eclipse installed, the versions of individual components of the Eclipseframework, and an inventory of all option or 3rd party plugins installed in a given environment. When you use MSE to simplify yourenvironment, you publish a Lineup to Nexus Team Edition.

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10.1.3. What is a Source Tree?

A Codebase includes one or more Source Trees. A Source Tree is a location in a Source Control Management system like Git orSubversion. For example, if your lineup needs to checkout projects from two internal corporate Subversion servers, your Lineupwould include two Source Trees pointing to two Subversion locations. A Source Tree can contain one or more Roots.

10.1.4. What is a Source Tree Root?

A Root is a location within a SCM repository which is imported into an Eclipse installation as a Maven project. If a Source Treedoes not define a list of Roots, it has an implicit root of “/”, this is the directory in which Maven Studio for Eclipse will look for aMaven POM to import. If you want to control the directories from which a project will be imported from a Source Tree, you woulddefine one or more Source Tree Roots.

For example, if you configured a Source Tree to point to the Subversion URL http://yourserver.com/svn/trunk, and you configureda Root at project-a/ and a Root at project-b/, MSE will checkout the source from these two directories and import these directoriesas Maven projects. Every defined Root must contain a Maven pom.xml file for a successful import.

10.1.5. Use Case for a Build Engineer

A Build Engineer uses Maven Studio for Eclipse to create a Codebase and publish this Codebase to a repository on Nexus TeamEdition. Once this Codebase has been published, the Build Engineer can then send a an e-mail to team members directing them toa one-click installation.

Nexus TeamMSE

Codebase

P2 Proxy

Maven Studiofor Eclipse

Figure 10.2. Maven Studio for Eclipse Interacting with Nexus Team Edition

10.2. Getting Started with Maven Studio for Eclipse

In this quickstart guide, you will:

1. Configure Nexus Team Server

2. Materialize the Sample Demo Maven Lineup

3. Create a Custom MSE Codebase

4. Configure a Custom MSE Lineup

5. Configure an MSE Source Tree

6. Publish an MSE Codebase to Nexus Team Server

7. Materialize a Custom MSE Codebase

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10.2.1. Nexus Team Edition Prerequisites

Before starting the installation, make sure that you have satisfied the following preconditions for the server running Nexus TeamEdition:

• Nexus Team Edition must be installed on a server that does not have Nexus Open Source or Nexus Professional installed on it.

• You are running a Java 6 Java Development Kit downloaded from Oracle on the server that will run Nexus Team Edition.

• You will need administrative privileges on the server running Nexus Team Edition.

10.2.2. Workstation Prerequisites

Before starting the installation, make sure that you have satisfied the following preconditions for the workstations which will berunning Maven Studio for Eclipse and materializing Eclipse installations from Nexus Team Edition:

• You have installed a Java Development Kit version 1.6.0_18 or higher from Oracle. Maven Studio for Eclipse requires a JDKversion of 1.6.0_18.

• If you are installing Maven Studio for Eclipse into an existing Eclipse installation, you must remove any previously installedversion of the m2eclipse plugin.

10.3. Installing Nexus Team EditionThe first step for setting up your environment for Maven Studio for Eclipse is to install Nexus Team Edition.

10.3.1. Download Nexus Team Edition

If you are reading this quickstart guide, you should have received an e-mail from Sonatype containing instructions for downloadingNexus Team Edition.

Download the nexus-team-webapp-1.6.1.1-bundle.tar.gz or nexus-webapp-1.6.1.1-bundle.zip archive to the server which is goingto host Nexus.

10.3.2. Unpack Nexus Team Edition

After downloading the Nexus Team Edition archive, unpack the archive:

• On a Linux machine, you might install Nexus Team Edition in /usr/local/nexus-team-1.6.1.1 or /opt/nexus-team-1.6.1.1.

• On a Windows machine, you might choose to install Nexus Team Edition in c:\Program Files\Nexus Team.

10.3.3. Start Nexus Team Edition

To start Nexus Team Edition locate the appropriate platform directory under ${NEXUS_HOME}/bin/jsw

• On Windows, run nexus.bat to start Nexus.

• On OSX or Linux, run nexus start to start Nexus, and nexus stop to stop Nexus.

Note

On Windows, you may be prompted to allow the service to modify the Windows Firewall.

10.3.4. Login as a Nexus Administrator

Go to http://localhost:8081/nexus, and login with the default administrator credentials: Username: admin, Password: admin123

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Figure 10.3. Login to Nexus Team Edition

10.4. Configure Nexus Team ServerOnce you have installed the Nexus Team Edition, you must configure a few Nexus Server settings which will affect the publishingof P2 Lineups.

10.4.1. Open the Nexus Server Configuration Panel

To configure your Nexus Server, open up the Server configuration panel by selecting Administration # Server from the Nexus menu.

Figure 10.4. Opening the Server Configuration Panel

10.4.2. Configure Proxy Settings

If your Nexus Server needs to use an HTTP Proxy, you must configure the proxy settings in the Nexus Server configuration.

Figure 10.5. Opening the Server Configuration Panel

10.4.3. Save the Nexus Server Configuration

Click on Server Configuration panel’s Save button to save your Nexus server configuration.

10.4.4. Add a New P2 Proxy Repository

Next, add a new P2 Proxy Repository for the Eclipse Checkstyle (eclipse-cs) plugin. Later on in this guide, you will be creatinga custom Lineup which includes the Eclipse Checkstyle plugin. Go to Views/Repositories -> Repositories, and click on the Add...button. Select Proxy Repository.

Figure 10.6. Adding a New P2 Proxy Repository

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10.4.5. Configure the New Proxy Repository

Once you’ve created the New Proxy repository, configure the following parameters for the new repository:

Figure 10.7. Configuring New Proxy Repository for Checkstyle Plugin

10.5. Run the Publish Lineups Scheduled Task in Nexus Team ServerAfter configuring your Nexus Team server, you must create a Scheduled Task to Publish a P2 Repository Lineup.

10.5.1. Execute a Scheduled Task for P2 Lineups

To execute a scheduled task, click on Administration # Scheduled Tasks in the Nexus Menu. Locate the “Publish P2 Lineup” Job inthe list of configured tasks. Right-click on this task, and select Run.

Figure 10.8. Opening the Scheduled Tasks Configuration Panel

Click Yes in the confirmation dialog to execute the Scheduled Task.

10.5.2. Verify P2 Lineups are Published

After running the job, click on the Refresh button in the Scheduled Tasks panel as shown in the following figure.

Figure 10.9. Running the P2 Lineup Publishing Task

While the job is running, the Status is RUNNING. This job will run for approximately 1-3 minutes. While the job is running, pressthe Refresh button to refresh the status of the running job. Once the Job is completed, the status will change to SUBMITTED asshown in the following figure.

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Figure 10.10. Verify the Completion of the P2 Lineup Publishing Task

10.6. Materialize a Sample WorkspaceOnce you’ve configured Nexus Team server and published the demo P2 lineups, you are ready to materialize one of the demoworkspaces. In this quickstart guide, you are going to materialize the sample Maven workspace. Once this workspace is materialized,you can then use Maven Studio for Eclipse to create your own custom P2 lineups.

10.6.1. Open the Repositories Panel

To open the Repositories Panel, click on Views/Repositories -> Repositories. Once the Repositories panel is open, you should seea list of all of the User Managed Repositories.

10.6.2. Select Nexus Managed Repositories

The MSE Codebase Repository is a Nexus Managed Repository. To view all Nexus Managed Repositories, select Nexus ManagedRepositories from the repository type drop down.

Figure 10.11. Viewing Nexus Managed Repositories

10.6.3. Select Sonatype MSE Repository

In the list of Nexus Managed Repositories, select the MSE Codebase Repository. This repository contains the sample Apache Mavenlineup.

Figure 10.12. Selecting the Onboarding Repositories

10.6.4. Click on the MSE Installer for the Maven Lineup

Maven Studio for Eclipse ships with a demonstration project: the Apache Maven project. The first thing you will want to do ismaterialize one of these lineups to get a fully functioning installation of Maven Studio for Eclipse.

Once you select the Onboarding Project Repository, go to the Browse Storage tab and navigate to the org/sonatype/mse/codebases/demo-maven/0.0.1 folder. Right-click on the mse-codebase.jnlp file and choose Download.

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Figure 10.13. Downloading the Demo Maven Installer

10.6.5. Run the MSE Installer

When you download the mse-codebase.jnlp file, Java Web Start will download, verify, and start the MSE Installer. If this is the firsttime you are running the MSE Installer, you will be asked to verify that the MSE Installer is trusted.

Figure 10.14. Running the MSE Installer

10.6.6. Supply Server and Source Control Credentials

You will then be asked to supply credentials for any source code repository or server involved in the installation process. Check theAnonymous access checkbox to the right of the Username field and click on the Next button.

Figure 10.15. Supply Subversion and Source Control Credentials

Once you click next, the M2E installer will validate that is can connect to the source code repository and Nexus. Click Next on thefollowing dialog:

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Figure 10.16. Successful Validation of MSE Installer Requirements

10.6.7. Specify Installation Directories

Next, the MSE installer will ask you to supply two directories: The Installation Directory, where the MSE Installer installs Eclipse,and the Workspace Location, where MSE Installer puts projects and code. You can Supply custom directories or accept the defaultvalues supplied by the MSE installer.

Figure 10.17. Supplying Installation Directories for MSE Installer

10.6.8. Verify Completed Eclipse Installation

Clicking on Finish will start the process of installing the Eclipse IDE with all of the plugins specified in the MSE Lineup. Once theinstallation is completed, you should see an Eclipse IDE installation.

Note

Windows may prompt you to authorize the Eclipse IDE the first time it has been launched. You may see a firewalldialog asking for permission to execute Eclipse. You should approve this request.

Once the Eclipse IDE is visible, give the tool a few minutes to update indexes and to checkout project source code from sourcecontrol. Once this process is finished, you should see a list of projects in the Apache Maven project. Once the Eclipse workspace hasbeen materialized, you can start to work with the projects it checked out.

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Figure 10.18. Maven Projects Displayed in Eclipse

10.6.9. Configure Password Recovery

On some platforms, Eclipse will then prompt you to set up the Master Password and Password Recovery options in Eclipse. ClickYes in the Secure Storage dialog.

Figure 10.19. Creating a Master Password for Eclipse Password Recovery

In the Password Recovery dialog type in two questions that will allow you to recover the master password for this Eclipse workspace.Once you’ve typed in these questions and answer, click OK.

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Figure 10.20. Configuring Password Recovery

10.7. Creating a New MSE Lineup

Maven Studio for Eclipse gives you the tools you need to define a custom Eclipse installation which can be materialized with asimple click of a button. If you’ve followed the instructions in this document, you’ve already used that capability to materialize thedemonstration instance of Maven Studio for Eclipse which contains the Maven project.

Next, you are going to use the custom lineup capabilities of Maven Studio for Eclipse to define a custom lineup which will checkoutsource code from a Subversion repository.

10.7.1. Create a New MSE Lineup Project

To create a new MSE Lineup, click on File -> New --> Other... in Eclipse as shown in the figure below.

Figure 10.21. Creating a New Lineup Project (Select New -> Other)

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10.7.2. Select the New P2 Lineup Wizard

Next, select New P2 Lineup from the Maven Studio for Eclipse folder in the wizard selection dialog.

Figure 10.22. Creating a New Lineup Project (Select New P2 Lineup Wizard)

10.7.3. Configure Nexus and Lineup Coordinates

Clicking Next will display a dialog that contains the Nexus Server URL, the Nexus credentials used to connect to Nexus, and theLineup Coordinates.

Enter your administrative credentials for Eclipse in this dialog and supply Lineup Coordinates for your MSE Lineup. Change theGroup Id to “com.sample” or choose a group identifier that makes sense for your organization. Click on Next.

Figure 10.23. Supply Lineup Coordinates and Nexus Credentials

Note

Every artifact in Nexus has a coordinate which consists of a Group ID, Artifact ID, and Version. The Group ID groupsprojects together and is often unique to an organization or a project. The Artifact ID is a unique identifier for a project(or in this case a Lineup).

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10.7.4. Select Runtime Platform and Memory

Select the platforms that are appropriate for your platform, Specify the heap size for your Eclipse installation in megabytes, and checkthe “Load Installable Units from Current Eclipse Installation” checkbox.

Figure 10.24. Select Runtime Platform and Memory

NoteIf you select “Load Installable Units from Current Eclipse Installation”, Maven Studio for Eclipse will use the currentEclipse installation as a template for your new P2 Lineup.

10.7.5. Configure the Contents of the Lineup

The next step in the P2 Lineup wizard is the Lineup Editor. This interface is where you configure the contents of the P2 Lineup. Youcan configure which Eclipse components and plugins are installed in a materialized Eclipse installation.

Figure 10.25. Configuring Contents of a P2 Lineup

The first list of “Installable Units” are the plugins and components that are installed in your Eclipse installation. The defaultcomponents are Maven Studio Materialization Support and Sonatype Studio Base IDE Lineup. These two components are requiredfor all Maven Studio for Eclipse installations. Note that the version number for Maven Studio Materialization Support is 0.0.0. Thisspecial “0.0.0” version number tells Eclipse to install the latest version currently available.

If you selected “Load Installable Units from Current Eclipse Installation” in the previous step, this list should contain Eclipse plugins,components, and update sites configured in your current Eclipse installation.

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10.7.6. Add a New Repository

Click on the Add... button in the Lineup Editor.

Figure 10.26. Adding the Checkstyle Repository to the Lineup Editor

Name the new repository “Eclipse-Checkstyle Integration” and use a Location of: http://eclipse-cs.sf.net/update/

10.7.7. Add the Checkstyle Plugin Installable Unit

After adding the repository, click on OK. Then in the Lineup Editor add a new Installable Unit by clicking on Add... next to thelist of Installable Units. Enter “http://eclipse-cs.sf.net/update” into the Work with: field, press Enter, and then select the most recentversion of the Checkstyle plugin.

Figure 10.27. Adding the Checkstyle Installable Unit to the Lineup Editor

10.7.8. Verify the P2 Lineup

Once you have added the Checkstyle repository and the Checkstyle plugin as an installable unit, click on the Next button. When youclick on Next, Maven Studio for Eclipse will verify that it has access to the appropriate proxy repositories on Nexus Team server.

Figure 10.28. Verifying the Lineup Summary

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Clicking Finish will create the P2 Lineup in your workspace under the Artifact ID of your new lineup.

Figure 10.29. Viewing Your New Codebase in the Eclipse IDE

10.8. Configuring a New Codebase

Once you’ve created and configured your P2 Lineup, you will need to configure a Source Tree for your Codebase. When you configurea P2 Lineup, you are telling Maven Studio for Eclipse what Eclipse components and plugins to install when it materializes an Eclipseinstallation from your Nexus Team server. Once Maven Studio for Eclipse materializes an Eclipse installation it will also checkoutMaven projects from source control.

In this section, you are going to configure your newly created Codebase to checkout source code from an open source Subversionrepository. In a corporate environment, instead of configuring your Codebase to pull projects from an Open Source project, youwould be configuring your Codebase to pull projects from your own source control system.

If the baseline Codebase Overview is not already loaded, click on mse-codebase.xml in the misc folder under the baselineup projectin your Eclipse workspace.

10.8.1. Maximize the Codebase Overview

If you just completed the previous section and defined a P2 Lineup, you should see the Codebase Overview in your Eclipseenvironment.

Maximize the Codebase Overview by clicking on the maximize button as shown below.

Figure 10.30. Maximizing the Codebase Overview

Once you have maximized the Codebase Overview, you will see the following form.

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Figure 10.31. Codebase Overview

10.8.2. Create a New Source Tree

A Source Tree is a collection of projects checked out from source control.

Figure 10.32. Creating a New Source Tree

Click on Create... under Source Trees and name your new Source Tree “Apache Commons”. Then click on OK.

10.8.3. Configure the New Source Tree

Once you create a new Source Tree, the Codebase Overview will switch to a form that allows you to configure a new Source Tree. Thisdialog will show information about the source tree, the SCM location, Roots in the Source Tree, and information about the project.

10.8.4. Configure the SCM Location

Click on the drop down next to SCM Location and select “svn” as the Source Control protocol. Then type the following URL intothe SVN location: http://svn.apache.org/repos/asf/commons/proper/lang/trunk

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Figure 10.33. Configuring the Commons Source Tree

Click on Validate Access. Maven Studio for Eclipse will then attempt to access the source code repository to validate that you haveaccess to this URL.

10.8.5. Add a Feed URL

Click on Create... under Feeds and add in the following URL for this mailing list feed: http://mail-archive.apache.org/mod_mbox/commons-user/?format=atom

Click on OK.

Figure 10.34. Configuring the Commons Feed URL

10.9. Publishing a CodebaseOnce your P2 Lineup has been configured with a Source Tree, you can publish this Lineup to your Nexus Team server.

If it isn’t already open, open the P2 Lineup overview, click on mse-codebase.xml under the baseline project in your Eclipse workspace.

10.9.1. Publish Your Codebase to Nexus

In the upper right-hand corner of the P2 Lineup Overview form you should see a Publish button next to a server icon.

Figure 10.35. Publish Button on Codebase Overview

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Clicking on this Publish button will tell Maven Studio for Eclipse to publish the newly configured P2 Lineup to your Nexus Teamserver.

If your Codebase has unsaved changed, Eclipse will ask you if you want to Save your current changes. Click Yes.

10.9.2. Supply Nexus Team URL and Credentials

Clicking the Publish button will display the Publish Codebase Descriptor dialog. In this dialog you will supply the Base URL of yourNexus Team server, a Nexus username, and a Nexus password.

Figure 10.36. Publish Codebase Descriptor

10.9.3. Publish the Codebase

Click OK, and Maven Studio for Eclipse will publish the Codebase to your Nexus Team Server.

Figure 10.37. Published Codebase Descriptor

After the Codebase has been published you can close Eclipse.

10.10. Materializing a Codebase

Once you have configured your Custom Codebase and published it to your Nexus Team Server you can test your new P2 Lineupby materializing it to your workstation. To do this follow the same steps you used to materialize the demonstation Maven lineupwhich shipped with Maven Studio for Eclipse.

10.10.1. Download the Codebase Installer

In Nexus Team server, select the Views/Repositories -> Repository panel, and then view the Nexus Managed Repositories. Selectthe MSE Codebase Repository and navigate to the com/mycompany/baselineup/1.0 folder. Right-click on the mse-codebase.jnlp fileand select Download.

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Figure 10.38. Select Published Codebase Descriptor

10.10.2. Supply Apache Subversion Credentials

Since the Codebase created and published in the previous section contains a Source Tree that points to the Apache Subversion server,you should leave Anonymous access checked and click on the Next button to continue.

Figure 10.39. Supply Subversion Credentials to MSE Installer

10.10.3. Supply Nexus Credentials

The MSE Installer will ask you for your Nexus credentials during the installation process. You should deselect the Anonymousaccess checkbox and supply your Nexus credentials. If you have not configured a new Nexus user, use the default credentials admin/admin123.

Figure 10.40. Supply Nexus Credentials to MSE Installer

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10.10.4. Configure Materialization Directories

Nexus supplies the directories for the materialization. If you want to override the default directories, specify an installation directoryfor the Eclipse installation and a workspace for your projects and workspace-specific configuration.

Figure 10.41. Choosing Installation Directories in the MSE Installer

10.10.5. Use Your Materialized Eclipse Installation

Once the materialization process is completed, you will have a customized installation of Eclipse complete with the Eclipse-Checkstyle plugin and the source code for Apache Commons Lang. You can use this same functionality to create custom, one-clicksolutions for developer on-boarding.

Figure 10.42. A Materialized, Custom, Eclipse Workspace

Figure 10.43. Checkstyle View from Materialized Workspae

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10.11. Troubleshooting Codebase MaterializationThis section attempts to summarize some of the problems that can occur during Nexus Team Edition installation and Codebasematerialization. If you encounter any problems or difficulties running through this quickstart chapter, please contact Sonatype atbook@sonatype.org1.

10.11.1. Reset Subversion Connection

The demonstration codebase contains source trees which depend upon public Subversion servers hosted by the Apache SoftwareFoundation. Although these servers are some of the most reliable and widely used source control systems you will find, you mightexperience problems during materialization if your connection is reset.

Figure 10.44. Subversion Connect Reset During Materialization

After the MSE Installer starts a newly installed Eclipse instance, it will attempt to checkout source code from the source treesconfigured in the codebase. If you see the error dialog shown in Figure 10.44, “Subversion Connect Reset During Materialization”,restart the materialization process. The connection to a Subversion server could be reset by either the server or the client, and themost likely scenario is that there was some brief downtime on the server-side. Running the materialization again should be enoughto fix this problem.

If the problem continues to happen even after a retry, you might want to investigate any process or system that mght be runninglocally to monitor and secure a network. Checking out a large project from a public Subversion server can involve a single, long-lived connection to a remote server. Make sure that there are no security systems terminating the connection to the remote Subversionserver on your end of the connection.

1 mailto:book@sonatype.org

Chapter 11. Managing MSE Codebases and P2Lineups11.1. IntroductionMaven Studio for Eclipse (MSE) gives you the ability to capture common configuration and projects for your developers with theDeveloper Onboarding feature. Using the Developer Onboarding feature, you can very quickly configure and deliver a commonconfiguration across your entire enterprise.

11.2. Creating a MSE CodebaseThere are two ways to create an MSE Codebase:

Create a new P2 LineupYou can create a new P2 Lineup which captures an Eclipse configuration including all components and plugins installed inEclipse. After creating and publishing a new P2 Lineup, Maven Studio for Eclipse will create a new Codebase and associateit with your new P2 Lineup.

Create a new MSE CodebaseAlternatively, you can create a new MSE Codebase. This newly created MSE Codebase will have an empty P2 Lineup URLwhich will need to be populated using a URL of a previously published P2 Lineup.

The following sections outline the details of both of these approaches.

11.2.1. Creating a New P2 Lineup

When you create a new P2 Lineup, you are configuring the Eclipse installation which will be associated with an MSE Codebase.This includes the versions of all components and plugins which will be installed by the MSE Installer. Your configuration will bevalidated against a Nexus Team Edition server to ensure that users will have access to P2 Proxy repositories for all the componentsrequired by your P2 Lineup.

To create a new P2 Lineup in Eclipse, go to File -> New and select Other... This will display the wizard selection dialog. Expand theMaven Studio for Eclipse folder, and select New P2 Lineup as shown in Figure 11.1, “Selecting the New P2 Lineup Wizard”.

Figure 11.1. Selecting the New P2 Lineup Wizard

The initial screen of the new P2 Lineup Wizard shown in Figure 11.2, “Initial Screen of Lineup Wizard: Lineup Setup” captureslineup coordinates and information about the target Nexus Team Edition server. A P2 Lineup is published to Nexus and stored witha set of lineup coordinates: Group Id, Artifact Id, and Version. These coordinates uniquely identify a published P2 Lineup.

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Figure 11.2. Initial Screen of Lineup Wizard: Lineup Setup

Clicking Next loads the Lineup Editor shown in Figure 11.3, “Editing a New P2 Lineup”. The Lineup Editor displays two sections:Installable Units and Repositories. The Installable Units section configures the plugins and components which are going to be installedas a part of the MSE Codebase materialization. There are two components which will always be a part of every MSE Codebase:

Maven Studio Materialization SupportThis component contains the framework which supports MSE Codebase materialization. The verion number 0.0.0 tells Eclipseto use the latest available version.

Sonatype Studio Base IDE LineupThis component combines the basic features of Sonatype Studio including support for Subversion, Git, and support for theSonatype m2eclipse component.

The Repositories section of the Lineup Edition contains all of the repositories required for a successful MSE Codebase materialization.You can add new repositories to this list to support the installation of addition installable units. For example, in Figure 11.3, “Editinga New P2 Lineup”, the Repositories section contains an extra repository http://eclipse-cs.sf.net/update. This repository correspondsto the Eclipse Checkstyle Plugin-in feature listed under Installable Units.

The Validate button in the Lineup Editor causes Maven Studio to connect to Nexus Team Edition and verify that all repositories andinstallable units are available. If you have added a new repository to the Lineup Editor, you will also need to add a new P2 Proxyrepository to Nexus Team Edition. The Manage Nexus repositories link below the Repositories section will load the repositories listin Nexus Team Edition. If you need to add additional P2 Proxy repositories to support custom lineups, click on this Manage NexusRepositories button and create any appropriate repositories in your Nexus Team Edition installation.

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Figure 11.3. Editing a New P2 Lineup

To a new an installable unit to a P2 Lineup, click on Add... next to the list of Installable Units in the Lineup Editor shown inFigure 11.3, “Editing a New P2 Lineup”. Clicking on Add... will load the Add Installable Unit dialog shown in Figure 11.4, “Addan Installable Unit to a P2 Lineup”. Select an existing repository, or paste a new Update Site URL into the Work with dropdownfield, then select the appropriate Installable Units in this dialog. Clicking on OK will then return you to the P2 Lineup Editor withthe Installation Units select added to the list of Installable Units configured for your new P2 Lineup.

Figure 11.4. Add an Installable Unit to a P2 Lineup

To add a repository to a P2 Lineup, click on Add... next to the list of repositories shown in Figure 11.3, “Editing a New P2 Lineup”.This will display the Add Repository dialog shown in Figure 11.5, “Add a Repository to a P2 Lineup”. When you add a repositoryto a P2 Lineup, you need to make sure that Nexus Team Edition has a matching P2 Proxy repository.

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Figure 11.5. Add a Repository to a P2 Lineup

Once you are finished configuring you new P2 Lineup in the Lineup Editor shown in Figure 11.3, “Editing a New P2 Lineup” clickNext. You will then see the New MSE Codebase Descriptor dialog shown in Figure 11.6, “Summary of New P2 Lineup Identifiers”.Clicking Finish will cause Sonatype Studio to publish the new P2 Lineup to Nexus Team Edition and open a new MSE CodebaseOverview form with the P2 Lineup field populated with the results of this wizard.

Figure 11.6. Summary of New P2 Lineup Identifiers

11.2.2. Creating a New MSE Codebase

If you already have a P2 Lineup configured, and you want to create a new MSE Codebase. You can create a new MSE Codebasedirectly by going to File -> New, selecting Other.... Expand the Maven Studio for Eclipse folder and then select New CodebaseProject as shown in Figure 11.7, “Selecting the New Codebase Project Wizard”.

Figure 11.7. Selecting the New Codebase Project Wizard

11.3. Configuring a MSE CodebaseOnce you create a codebase, you will see the Codebase Overview shown in Figure 11.8, “Codebase Overview”. The MSE Codebasesettings, MSE Source Trees, resources, and security are all configured from this interface. Once a Codebase has been properly

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configured, the codebase is saved as an XML file and then published to Nexus Team edition. The Codebase editor contains thefollowing sections:

Codebase InformationThis section contains identifiers, URLs, a name, a description, and a logo for the MSE Codebase. This section is describedin more detail in Section 11.4, “Configuring Codebase Information”.

Source TreesAn MSE Codebase contains one or more Source Trees. A source tree is a location in a source control server like Git orSubversion and it corresponds to a project or set of projects in an Eclipse environment. This section is described in more detailin Section 11.7, “Managing Codebase Source Trees”.

LocationsLocations holds URLs and resources which are associated with an MSE Codebase. The P2 Lineup Location points to a filehosted by Nexus Team Edition which describes the configuration of Eclipse, and the Maven Settings and Eclipse Preferencesassociate configuration data with an MSE Codebase. This section is described in more detail in Section 11.5, “ManagingCodebase Resource Locations”.

PrerequisitesThis section contains configuration values which affect the operation of Eclipse. This section is described in more detail inSection 11.6, “Setting Codebase Prerequisites”.

RealmsWhen the MSE Installer connects to remote resources to download settings, configuration, source control, or P2 Lineups, itstores credentials in Security Realms. This list of realms will be used to populate realm dropdownds throughout the Codebaseand Source Tree editors. This section is described in more detail in .

Figure 11.8. Codebase Overview

At the bottom of the Codebase Editor, you will see a series of tabs for each of the configured MSE Source Trees. Source trees arelocations in a source control system which correspond to one of more projects in an Eclipse workspace. The process for creating andmanaging source trees is described in more detail in Section 11.7, “Managing Codebase Source Trees”.

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Once a Codebase has been configured and saved, Maven Studio for Eclipse will have a project in the Project Explorer named afterthe Artifact ID of your Codebase which contains up to three files:

mse-codebase.xmlThis is the MSE Codebase descriptor, it is the XML file which is published to Nexus Team Edition, and which is used toconfigured the Java WebStart JNLP application which is used to start the MSE Installer.

mse-codebase-preferences.jarIf you have configured the MSE Codebase editor to generate, publish, and associate Eclipse preferences with an MSECodebase, this JAR file will contain an export of the selected Eclipse preferences.

mse-codebase-icon.pngThis is the 48x48 icon which is used to represent this MSE Codebase in an MSE Catalog.

Figure 11.9. Codebase Project Files

11.4. Configuring Codebase InformationThe Codebase Information section shown in Figure 11.10, “Configuring Codebase Information” contains identifiers, URLs, a name,a description, and an application icon for the Codebase. This section contains the following fields:

Group IdThe group Id is an arbitrary, organization or project-specific identifier which generally matches the reversed, period-delimited domain name of an organization plus any additional project identifiers. Examples: com.google, com.sonatype.nexus,org.apache.maven.

Artifact IdThe Codebase project identifier. This artifact id is used to identify a codebase as an Eclipse project. Examples: developersworking in the Ecommerce group would materialize a Codebase with an artifactId of "ecommerce".

VersionA version adheres to the following format: "<Major Version>.<Minor Version>.<Point Release>". Examples: The first versionof the "ecommerce" codebase may have a version number "1.0.0". A small update to this codebase would have the versionnumber "1.1.0", and a major revision would have a version of "2.0.0.".

NameThis field stores a descriptive name for a codebase.

DescriptionThis field contains a short, paragraph-long description of a codebase.

ImageEvery codebase can be associated with a 48x48 icon. Although this icon is not currently displayed by Nexus Team Edition orthe MSE Installer, this icon will be visible in the upcoming Maven Studio for Eclipse Catalog feature.

HomepageThis field contains a URL to the homepage associated with a codebase. This can be a page specific to the project or workgroupwhich is using this Codebase.

DocumentationThis field contains a URL to a documentation page to be associated with a Codebase.

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Figure 11.10. Configuring Codebase Information

11.5. Managing Codebase Resource Locations

In the MSE Codebase editor, the Locations section shown in Figure 11.11, “Configuring Codebase Resources” tracks importantconfiguration resources which can be associated with a Codebase. The resources are:

Security RealmThe MSE Installer will use a single security realm to access all of the resources listed in the Location section. Although thereare no restrictions for the URLs used in this section, the MSE Installer was designed with the expectation that all externalconfiguration resources would be downloaded from the same Nexus server.

P2 Lineup LocationIf you created your MSE Codebase using the New P2 Lineup wizard, the P2 Lineup wizard finished and then immediatelyloaded a new MSE Codebase with this field pre-populated. If you created a new MSE Codebase using the New MSE Codebasewizard, this field will be empty and you will need to supply a URL from Nexus Team edition.

Maven SettingsThis field contains a URL for your Maven Settings. Nexus Professional provides support for managing user-specific MavenSettings. To learn more about using Nexus Professional to manage and distribute Maven Settings, read "Managing MavenSettings"1 chapter in Repository Management with Nexus2. If you are using the default Maven Settings location in Nexus,your URL will resemble the following URL: http://localhost:8081/nexus/service/local/templates/settings/default/content

Eclipse PreferencesAn MSE Codebase can distribute a set of common Eclipse preferences to cature common configuration settings that covercode standards, Aspect-oriented programming settings, and m2eclipse configuration.

Figure 11.11. Configuring Codebase Resources

1 http://www.sonatype.com/books/nexus-book/reference/security.html2 http://www.sonatype.com/books/nexus-book/reference/security.html

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11.5.1. Publishing Eclipse Preferences

The MSE Codebase editor can capture your Eclipse preferences and publish them to a Nexus repository manager. Open the EclipsePreferences dialog shown in Figure 11.12, “Configuring Eclipse Preferences for a Codebase” by clicking on the Select... button inFigure 11.11, “Configuring Codebase Resources”.

To publish Eclipse preferences from the current Eclipse installation, select "Export workspace preferences" and select all of thepreference categories you want to publish in this MSE Codebase. The available preferences categories:

PROXYProxy configuration captures proxy configuration under General -> Network Connections from the Eclipse preferences.

JDTSelecting this group captures all configuration under the "Java" category from the Eclipse preferences.

M2ESelecting this group captures all configuration under the "Maven" category from the Eclipse preferences.

After configuring a codebase to publish Eclipse settings, save your Codebase and you should see a file named mse-codebase-preferences.jar associated with the MSE Codebase in the Project Explorer. When the Codebase is published to Nexus Team edition,this preferences JAR file will be published to the repository manager and associated with the published MSE Codebase.

You can associate an MSE Codebase with a set of previous published Eclipse preferences by selecting "External URL" and supplyingthe URL to a set of Eclipse preferences. The most common scenarios for using an existing, external URL is when an MSE Codebaseis referencing Eclipse preferences from another MSE Codebase.

Figure 11.12. Configuring Eclipse Preferences for a Codebase

11.5.2. Publishing Maven Settings

An important component of Maven configuration is a Maven Settings file usually stored in ~/.m2/settings.xml. This file containscredentials, profiles, and preferences which can use used to customize configuration variables for individual developers. Nexus TeamEdition and Nexus Professional Edition provide you with the ability to store and managed Maven Settings files for developers. Ifyou have configured Maven Settings in Nexus, you should supply the Template URL to the MSE Codebase editor. When the MSEInstaller materializes a new Eclipse installation it will download a settings.xml from the Template URL and interpolate that templatewith two substitution variables:

${baseurl}This is the Base URL for the Nexus server responsible for delivering the Maven Settings template. If you codebaseis configured to download Maven Settings from "http://central.example.org/nexus/server/local/templates/settings/default/content", the ${baseurl} will be replaced with "http://central.example.org/nexus/".

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${userId}This is the user identifier for the user making the request for Maven Settings. If your MSE Code contains a security realmfor Nexus, this ${userId} value in a settings.xml template will be replaced with the username supplied to the MSE Installerfor the Nexus realm.

Figure 11.10, “Configuring Codebase Information” shows the Maven Settings configuration panel from Nexus Team Edition. Toconfigure an MSE Codebase to download the "enterprise-webapp-team" Maven Settings template, you would supply the URL listedin the Template URL column to the MSE Codebase editor.

Figure 11.13. Configuring Codebase Information

To learn more about using Nexus Professional to manage and distribute Maven Settings, read "Managing Maven Settings"3 chapterin Repository Management with Nexus4.

11.6. Setting Codebase PrerequisitesThe Codebase editor contains a section to configure prerequisites. The Required Memory field shown in Figure 11.14, “ConfiguringCodebase Prerequisites” allows you to configure the validation criteria which must be satisfied before the MSE Installer willmaterialize a codebase. The MSE Installer will test the workstation to see if it has sufficient memory to perform a materialization.

Figure 11.14. Configuring Codebase Prerequisites

11.7. Managing Codebase Source TreesA Source Tree is a location in source control which corresponds to one or more projects in an Eclipse environment. To add anew Source Tree, click on the Create.. button next to the Source Trees section of the Codebase editor as shown in Figure 11.15,“Configuring Codebase Source Trees”.

3 http://www.sonatype.com/books/nexus-book/reference/security.html4 http://www.sonatype.com/books/nexus-book/reference/security.html

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Figure 11.15. Configuring Codebase Source Trees

To delete a Source Tree from an MSE Codebase, select the Codebase in the Source Trees section of the MSE Codebase editor andclick on the Delete button. Eclipse will then present you with a confirmation dialog to make sure that you really want to delete theselected Source Tree.

11.8. Configuring Codebase Security

Each Codebase is associated with one or more Security Realms. The MSE Installer stores credentials in secure storage in SecurityRealms. Create security realms for each resource that requires a separate set of credentials. The Realms section of the CodebaseOverview, as shown in Figure 11.16, “Configuring Codebase Realms”, contains the list of all realms used throughout an MSECodebae.

Figure 11.16. Configuring Codebase Realms

To add a new Security Realm to a Codebase, click on the Create... button shown in Figure 11.16, “Configuring Codebase Realms”and supply a new name for the Security Realm in the dialog shown in Figure 11.17, “Adding a New Security Realm”.

Figure 11.17. Adding a New Security Realm

11.9. Configuring a Source Tree

Every MSE Codebase can contain one or more Source Trees. A Source Tree is a location in source control containing one or moreMaven projects. To illustrate the relationship between a Codebase and a Source Tree, consider the example illustrated in Figure 11.18,“Two Codebases with an Overlapping Source Tree”. A company has two MSE Codebases: one codebase is used by a team whichdevelops a web application, another codebase is used by a team which develops a client-side application written in Swing. Bothteams use a common library, and both teams maintain a separate Subversion repository which contains team-specific code. Eachteam would have a custom MSE Codebase with two Source Trees, and both of these codebases would include a Source Tree forthe Common Library project.

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Swing Team

CodebaseWeb Team

Codebase

SwingApp

WebApp

CommonLibrary

Figure 11.18. Two Codebases with an Overlapping Source Tree

To open the Source Tree editor, go to the Codebase Overview, and click on one of the Source Tree tabs below the Codebase Overviewas shown in Figure 11.8, “Codebase Overview”. If there are no Source Trees to edit, create a Source Tree by following the directions inSection 11.7, “Managing Codebase Source Trees”. The Source Tree editor is shown in Figure 11.19, “Configuring an MSE CodebaseSource Tree”.

Figure 11.19. Configuring an MSE Codebase Source Tree

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11.9.1. Adding a Maven Profile

The Source Tree editor allows you to add a Maven Profile which will be made active for every project in a particular Source Tree.To add a new Maven Profile to a Source Tree, click on the Create button in th Profiles section of the Source Tree Overview shownin Figure 11.19, “Configuring an MSE Codebase Source Tree”. Once you click create, type in the name of the profile you wantactivated into the dialog shown in Figure 11.20, “Adding a Maven Profile”.

Figure 11.20. Adding a Maven Profile

11.9.2. Adding a New Feed URL

The Source Tree editor allows you to add feeds which will be made available to developers working with this materialized MSECodebase. To add a new Feed URL, click on Create in the Feed section of the Source Tree Overview shown in Figure 11.19,“Configuring an MSE Codebase Source Tree”.

Figure 11.21. Adding a New Feed URL

11.10. Publishing an MSE Codebase to Nexus Team Edition

An MSE Codebase is published to Nexus Team Edition where it is then made available to clients for materialization. To publish anMSE Codebase, open the Codebase Overview and click on the Publish button shown in Figure 11.22, “Codebase Publish Button”.

Figure 11.22. Codebase Publish Button

Clicking the Publish button will show the Publish Codebase Descriptor dialog shown in Figure 11.23, “Publish Codebase Dialog”.This dialog contains the URL and credentials that Maven Studio for Eclipse will use to connect to Nexus Team Edition. Clickingon the Publish button in this dialog will then cause Maven Studio for Eclipse to connect to Nexus Team Edition and transfer thecodebase to Nexus Team Edition.

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Figure 11.23. Publish Codebase Dialog

Appendix A. Creative Commons LicenseThis work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States license. Formore information about this license, see http://creativecommons.org/licenses/by-nc-nd/3.0/us/. You are free to share, copy, distribute,display, and perform the work under the following conditions:

• You must attribute the work to Sonatype, Inc. with a link to http://www.sonatype.com.

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When downloaded or distributed in a jurisdiction other than the United States of America, this work shall be covered by the appropriateported version of Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 license for the specific jurisdiction. If theCreative Commons Attribution-Noncommercial-No Derivative Works version 3.0 license is not available for a specific jurisdiction,this work shall be covered under the Creative Commons Attribution-Noncommercial-No Derivate Works version 2.5 license for thejurisdiction in which the work was downloaded or distributed. A comprehensive list of jurisdictions for which a Creative Commonslicense is available can be found on the Creative Commons International web site at http://creativecommons.org/international.

If no ported version of the Creative Commons license exists for a particular jurisdiction, this work shall be covered by thegeneric, unported Creative Commons Attribution-Noncommercial-No Derivative Works version 3.0 license available from http://creativecommons.org/licenses/by-nc-nd/3.0/.

A.1. Creative Commons BY-NC-ND 3.0 US LicenseCreative Commons Attribution-NonCommercial-NoDerivs 3.0 United States1

THE WORK (AS DEFINED BELOW) IS PROVIDED UNDER THE TERMS OF THIS CREATIVE COMMONS PUBLICLICENSE ("CCPL" OR "LICENSE"). THE WORK IS PROTECTED BY COPYRIGHT AND/OR OTHER APPLICABLELAW. ANY USE OF THE WORK OTHER THAN AS AUTHORIZED UNDER THIS LICENSE OR COPYRIGHT LAW ISPROHIBITED.

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Creative Commons may be contacted at http://creativecommons.org/.

Appendix B. Book Revision HistoryThe following sections list changes made to the book in reverse chronological order starting with 1.1.

B.1. Changes in Edition 0.8The following changes were introduced in Edition 0.8 on February 15, 2010:

• Updated book to cover m2eclipse 0.10.0. (MEBOOK-491)

• Updated Section 2.3.3.1, “Installing Subclipse” (MEBOOK-522)

• Updated Section 2.3.3.2, “Installing Mylyn” (MEBOOK-533)

• Updated Section 2.3.3.3, “Installing the Web Tools Platform (WTP)” (MEBOOK-544)

• Added Section 2.1, “Installing the Eclipse IDE” (MEBOOK-575)

• Update Chapter 2, Installing m2eclipse to provide instructions for an Eclipse 3.5 plugin installation. The initial versions of thisbook discuss Eclipse 3.2 which had a different approach to installing Eclipse plugins. (MEBOOK-566)

• Removed reference to AJDT support. (MEBOOK-507)

• Chapter 2, Installing m2eclipse now discusses the Core and Extras update sites. (MEBOOK-558)

B.2. Changes in Edition 0.7The following changes were introduced in Edition 0.7 on November 16, 2009:

• Created a new chapter Chapter 3, Creating and Importing Projects. (MEBOOK-409)

B.3. Changes in Edition 0.6The following changes were introduced in Edition 0.6 on September 15, 2009:

• Modified project to generate a PDF for pre-print:

• Embedded the fonts in the generated PDF. (MEBOOK-1710)

• Resized book to Royal Quarto (7.444" x 9.681"). (MEBOOK-1611)

• Added a Title Page to the PDF. (MEBOOK-2112)

• Added a blank page to the end of the PDF. (MEBOOK-2013)

• Automated the production of print and web figures. (MEBOOK-2314)

• Standardized on 0.5" Margins. (MEBOOK-2215)

• Added the appropriate roles to all imageobjects. (MEBOOK-1816)

• Assigned the book an ISBN. (MEBOOK-3217)

• Added the full text of the Creative Commons license to the front matter. (MEBOOK-3318)

• Fixed a typo: redundant mention of Subversion in Section 3.1.1, “Checking Out a Maven Project from SCM”. (MEBOOK-1219)

108

• Fixed a typo: capitalized "eclipse" in Section 8.1.3, “Resolving Dependencies”. (MEBOOK-920)

• Added clarification about the availability of the Form-based POM Editor to Section 8.2, “Using the Form-based POM Editor”.(MEBOOK-821)

• Added new section about the Maven Repository view: ???. (MEBOOK-1922)

• Address feedback from Proofread of Edition 0.5 PDF:

• Fixed a typo: removed duplicate "about" from page 29. (MEBOOK-2823)

• Removed extraneous space from page 28: (MEBOOK-2924)

• Fixed a spelling error on page 51. (MEBOOK-2525)

Index