naam adf development more tales from the trenches aino andriessen amis services

NAAM

ADF DevelopmentMore tales from the

trenchesAino Andriessen

AMIS Services

• Systems integrator• Co-sourcing• Maintenance• Oracle, Java, Open Source, ADF, DBA, SOA• AMIS technology school• Pagoni

• http://www.amis.nl• http://technology.amis.nl/blog/

Aino Andriessen• Technical Consultant• Technical Architect• Java, ADF, PL/SQL, XML, ...• SOA , Integration• Software engineering• Quality management• Agile development

• aino.andriessen@amis.nl• http://www.fttech.net

Stakeholders

customer

project lead

maintenancedeveloper

better according to... Customer

better according to... Project lead

better according to... Developer

better according to... Maintenance

better according to... Girlfriend

• How can we make better ADF applications?

5 essentials

• Communication• Responsibility• Knowledge• Organization• Fun

• Let's start coding...

• Sorry, not yet...

Organization...• Project• Development process• Skills• Project structure (file structure)• Code• Design and Architecture• Documentation• Communication• Infrastructure

Delivery environments

Library

Developer2Developer

2

Custom

Production

Developer2Developer

Source control

CorporateLibrary

Build automation

Test

Documentationsite

Development

Issue management

Tests

Inspection

Public Library

Reports

Documentation

Issue reports

Acceptance

Integration

• Can we now start coding?

• Almost...

Development principles

• OK, wake up and let's get to business...

• Build an ADF - JHeadstart application• Address common and not so common issues• ADF 10g

– Some 11g

Demo

• Regatta Management System

• Application to support sailing regatta's. – maintain regatta's– registration– enter racing data– results

Development Goal

• Match implementation against stakeholders' concerns :– Functional– Maintainable– Stable– Budget– Organized– Fun– . . .

Business Logic implementation• Business Logic can be implemented at many locations

– ADF Faces components• Managed beans• Backing beans• EL-expressions• Attributes

– Service methods– VO's

• Attributes : transient, calculated• Methods

– Entities• Attributes• Validators

– Database• Constraints• Views• Stored procedures

– ...

The (ADF) challenge

• Consistent and comprehensible implementation of business logic.

FD• Requirements

– Maintain regatta information– Allow sailors / boats to enter a regatta.

• Register skipper and captain (owner) with some personal details– Schedule racings– Easy registration of race details, only by certain people– Publish results– Nice look and feel– Easy to use– Handle handicap system

• Business rules– Participant, skipper, must be older than 18– Same boat may enter only once– Finishtime after starttime– Participant can have only one result– It should be able to reset the finish of a participants, in case of error– Register if the boat didn't start or finish, using the common codes like DNF, DNS, DSQ etc.

• Extra information about this situation must be entered– Races cannot be scheduled at the same time

Functions / Use cases

• Maintain regatta's• Register for a regatta• Enter racing data• Publish results• Supportive functions

ADF 'architecture'

• ADF applications tend to evolve instead of being designed.– Viewobjects are created when needed– Managed beans are created as needed– Application Modules function merely as a service-hatch

• ADF doesn't force you into an organized application, except maybe the model and viewController.

• ADF offers multiple solutions for the same problem and in the end all of them will eventually appear in the application.

ADF architecture

Database

ADF Faces

ADF model (binding)

ADF BC

ADF architecture

Database

ADF Faces

ADF model (binding)

ADF BC

Managed beans

Application Modules

ViewObjects

EntitiesObjects

ViewsStored Procedures

Tables

Application Integration

ADF Application

DatabaseWebservices

Files Messaging

Notification

Function / Use Case approach

• The application module, the service, is the core of the application

• Each function / use case is implemented as a service.

• Services can be nested

ADF architecture

Database

ADF Faces

ADF model (binding)

ADF BC

Webservices

Webservices

Files Messaging

Notification

Service Service Service Service Service

RMS Services

Datamodel

Datamodel 2

• Views– 1 : 1 on tables : vpd, – complex queries

• Stored procedures• app_owner and app_user

Development

Development environment

• JDeveloper 10g 10.1.3.4• JHeadstart 10g 10.1.3.3• Oracle 11g R1• OC4J 10.1.3.4• Maven 2.1• Subversion 1.5

JDeveloper Setup• External tools

• Encoding UTF-8– Preferences -> Environment

• Upgrade JDev svn client to 1.5– http://technology.amis.nl/blog/5253/upgrade-jdeveloper-

10g-subversion-client

JDeveloper

• Organize imports• Define .vm as text file

– preferences -> filetypes

• Default editors : source– preferences -> filetypes

Project setup

Projects

common General code, Baseclasses

Reusable's

database Database code, scripts

deployment (automated) Deploy to iAS

ear Build deliverable, ear

model ADF BC's

viewController UI

ADF Faces

lib 'External' libraries

Maven conventions - code

Maven conventions - unittests

General

• SRDemo• JHeadstart framework• Weblogs• Documentation

– Developer’s Guide For Forms/4GL Developers

• Simple Emp reference project

BC Creation

Default - create BC's from table

Default - create BC's from table

BC creation

1. Services2. Entities3. Associations4. Viewobjects5. Viewlinks6. VO usages

• Apply naming conventions– Refactor if needed

• Organize, organize, organize

Create Entities

• Create Business components from table– Refactor associations

• Base on table, change later to database view

Edit entities

• Set Id from sequence

– DBSequence is a nightmare to refactor

• Control Hints

– Enter once, use often

Associations

• Association properties– apply correct plural and singular

• Define Composition Association– Developer’s Guide For Forms/4GL

Developers - Chapter 6.3.3

Business rulesBR Implementation

Participant, skipper, must be older than 18

Same boat may enter only once

Finishtime after starttime

Participant can have only one result

It should be able to reset the finish of a participants, in case of error

Register if the boat didn't start or finish, using the common codes like DNF, DNS, DSQ etc.

Extra information about this situation must be entered

Races cannot be scheduled at the same time

A boat either has a finishtime or a special situation

Entity validation

FE or DB or 'complex' entity

Unique key

FE function

Datamodel, domain

FE, mandatory dependency

Unique key?

Row validation

Unique key

Entity Business Rules• Mandatory, PK, UK• Validation

– Declarative– Method– Rules

• Declare in project properties– Very Reusable

• [Entity constraint]– NO validation– Only present for creating table from entity

Validators / Rules

• Create Registered Rule in project properties– Or reuse an existing one

• Implement code in validateValue method

Validators

• Select the Rule as attribute validation• Test

Entity Validation - remarks• The setter immediate triggers the validation

– actually the setAttributeInternal(...)• Validations are executed top to bottom• Row validation is performed 'independent' of attribute validation.• Declarative Date validators are limited

– Use Validators• Using a select statement for validation is very limited (if it works at

all)– Avoid it.

• Consider Validator when the same validation is entered multiple times.

• Validator exception msg not published to the front-end (as we'll see later)

(J)Unittesting Entities

• Create Application Module :

• Create entity :

import oracle.jbo.client.Configuration;

RegistrationServiceImpl _am;

public void setUp() { _am = Configuration.createRootApplicationModule ("nl.amis.demo.rms.model.services.RegistrationService" ,"RegistrationServiceLocalURL");}public void tearDown () { Configuration.releaseRootApplicationModule(_am, true);}

EntityDefImpl empdef = (EntityDefImpl)EntityDefImpl.findDefObject ("nl.amis.demo.rms.model.entities.CrewMember");

crewMember = (CrewMemberImpl)empdef.createInstance2 (_am.getDBTransaction(), null);

• Execute test :Date testDate = (Date)Date.getCurrentDate();try { crewMember.setBirthdate(testDate); fail();}catch (Exception e) { e.printStackTrace();}

testDate = (Date)testDate.addMonths(-12*20);try { crewMember.setBirthdate(testDate);}catch (Exception e) { fail(); e.printStackTrace();}

Unit-testing

↑ code control ↑ code quality↓ development time

• 'Automatic' regression test• TDD improves the testability of your code• Unit-testing increases your ADF skills• Easy debugging of BC's• Automated execution at continuous integration

Unittest framework

• TestBase per application module– provide ServiceImpl

• Utility methods– Create entity

• Standardization– Authorization– Context

I don't write unittests because it takes too much time

Gee, How long does that take?

Then, how do you test your code?

I'll start the application, login, navigate to the right screen and then perform the correct actions?

VO Remarks• Often screen, Use Case driven• Organize

– the number may increase rapidly– Separate list-only VO's

• Apply naming conventions– plural– Lkp– Trnsnt– ...By...

• Don't use 'automatic BC creation from database'– Unless you like refactoring...

VO remarks

• Calculated attributes are not updated automatically, but need a requery– This may often result in complex code

Domain driven logic

• NoFinishCode– DSQ, DNF, DNS

• define constants or enum

• IsXXX attributes

VO client interface methods

• Implement VO related functions– startRace()– disqualifyParticipant()– ..

• Maybe also published as Service interface method

• Beware with nested applicationmodules to bind the correct method– or else the getCurrentRow does not work– NB, bindings work ok

Bindings and Nested AM

Viewobject validation

• Override validate() method• setter method• throw JboException

– define your own

View object usages

• Naming conventions• Organize them in services

Unittesting VO's (Usages)

• Basic test– executeQuery

• Business Logic• Beware of detail VO's

– they are direct available on the AM, but relate to their parent

Programmatic viewobjects

• e.g. for Webservice clients• See Developer’s Guide For Forms/4GL Developers -

Chapter 9 • JhsProgrammaticViewObject

– getJhsProgrammaticResultSet• ! Executed many times

– Override executeQuery() to actually retrieve data– Store result in JhsProgrammaticResultSet class variable– Convert using JhsProgrammaticHelper.convertBean

• Match attributes with ws return object

Re-use• Bases classes• Validators• Unittest utilities• Date handling• ADF Binding (model) methods

– SRDemo : JSFUtils and ADFUtils• JHeadstart templates• Business Components• Task flows• Beans• Converters• Filters• ...

Organize Re-use

• Separate projects, libraries, and owners• Review / audit criteria

Reuse BC's

• Separate project• Create deliverable• Add jar to project• Import jar

• Beware, sharing database connection from root application module

Refactoring BC's

• http://technology.amis.nl/blog/2859/fear-for-renaming-refactoring-adf-bc-objects-in-jdeveloper-is-not-unfounded

• Renaming and moving BC's is handled quite well.• Bindings are not automatically adjusted• JHeadstart is not automatically updated

– Generation errors– Just reselect the attribute / group

• Try to be strongly typed

Refactoring remarks

• Matching subversion clients• Refactoring DBSequence attributes is a pain...• ADF does not always allow you to refactor, in

case of dependencies.• Validator

– Re-registration of the Rule

• Beware of static 'dependencies' in the JHeadstart templates

JHeadstart

• One application definition vs. multiple– Can merge and split quite easily– 11g support for multiple improved

• JHeadstart supports nested application modules• Apply standards and naming conventions• Configuration

– tools -> preferences• e.g. item prompt

– AppDef root node• AM superclass

Custom Templates

• Application hierarchy matches the default• Documentation of templates• Try to avoid hard-coded bindings

– difficult to refactor– custom properties

• Buttons can be generated – however, the binding is not

Common recommendations

• Understand the framework• Avoid 'bindings', use a managed bean and

dependencies• Custom bindings : Disable 'Clear Page

Definition'• Close pagedefs before generation

Date and time

• Using Java Date and Calendar and oracle.jbo.domain.Date and Timestamp can be tricky– new oracle.jbo.domain.Date() ?

– new oracle.jbo.domain.Timestamp() ?

– Date.getCurrentDate() ?

– ((Date)Date.getCurrentDate()).timestampValue

• actually java.sql.Timestamp

• Current time?

Date and time - Calendar

Calendar c = Calendar.getInstance();

oracle.jbo.domain.Timestamp ts =

new Timestamp(c.getTime());

Timestamp ts =

new Timestamp(c. getTimeInMillis());

c.set(Calendar.HOUR_OF_DAY,5)

Date Time - JodaTimeDateTime dt = new DateTime();Timestamp ts = new Timestamp(dt.getMillis());

DateTime dt=new Da dt.getHourOfDay(); dt.plusMinutes(10); dt.minusWeeks(5); dt.isAfter(dt2); dt.isBefore(dt2); dt.isBeforeNow();teTime(2009,6,14,13,0,0,0)

Search Programmatic viewobject

• Standard JHeadstart Search – Allows searching using the VO attributes– Creates 'SQL formatted' ViewCriteria

• oracle.jheadstart.model.QueryCondition• unusable for Programmatic viewobject

1. Somehow retrieve actual data from viewcriteria1. Strip the formatting

2. Provide the actual value1. e.g. via the oracle.jheadstart.model.QueryCondition2. Override JhsApplicationModuleImpl.advancedSearch()

Store search criteria• On login requery the latest search

• Extend JhsSearchBean• Override advancedSearch()

– Serialize the criteria to file– Use the userId as name for the file

• Constructor– Retrieve the criteria from file

• http://groups.google.com/group/adf-methodology