02.egovframe training book_overview_supplement_en.pdf

8/12/2019 02.eGovFrame Training Book_Overview_Supplement_EN.pdf

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eGovFrame Training ook II

eGovFrame Center2013


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Table of contents

DI(Dependency Injection), IoC(Inversion of Control)

AOP (Aspect Oriented Programming)

MVC (Model, View, Controller) pattern concept

Architecture based on eGovFrame

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I

II

III

IV


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DI (Dependency Injection), IoC (Inversion of Control)

public class MovieLister{ public void list() {

MovieFinder finder = new MovieFinderImpl();}

}

public class MovieLister{ public void list() {

MovieFinder finder = Assember.getBean("movieFinder");

}}

Change the flow of control between classes and reducing dependence(Ease

of maintainability)

When change Impl class, need to change Lister as well

Assembler manages dependency

Composition of eGovFrame


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AOP (Aspect Oriented Programming)(1/2)

AOP is a programming paradigm which aims to increase

modularity by allowing the separation of cross-cutting concerns.

Separate add-on services (ex: logging, security, exception, etc)that are repeated in a number of biz logic code in an information

system as Aspect. Make that a separate module and maintain a program with configuration files.

When changes occur in additional functions(add-ons), simply bychanging Aspect, the change can be reflected to the biz logic codeand the maintenance of the code will be much easier.

Improve readability as removing duplicated code in business logic.



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AOP (Aspect Oriented Programming)(2/2) Composition of eGovFrame

[ Separating Aspect] [ Weaving]

Aspect : A modularization of a concern that cuts across multiple objects

Join point : A point during the execution of a program, such as the execution of a method or the

handling of an exceptionAdvice : Action taken by an aspect at a particular join point

Pointcut : A predicate that matches join points. Advice is associated with a pointcut expression andruns at any join point matched by the pointcut (for example, the execution of a method with acertain name)

Weaving : Linking aspects with other application types or objects to create an advised object

CreditTransfer

DepositWithdraw

Calculatinginterest

Logging

Security

Transaction

Core Concerns

CrosscuttingConcerns

Core ConcernsModule

Calculatinginterest

Deposit

Withdraw

CreditTransfer

CrosscuttingConcerns Module

Logging

SecurityWeaving


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Object Relational Mapping(ORM)

Features General Development ORM based

Apply Mapping Need direct mapping java classes to the tablecolumns

Developers can be processed directly in terms of object-oriented

FlexibilityWhen SQL changes, directly modify source code

and deployCan be applied only with modifications of the mapping

information

Standard Pattern No patternMapping information, XML, etc can be applied in the form

of template

DB Control Directly control DB In case of Mapping, direct control can be difficult

Technology in use SQL Persistence framework (Hibernate, iBatis)


SQL

Java-Mapping

Business LogicBusiness Logic

DB Column Java ClassMapping

JDBC

DataBase

JDBC

DataBaseBusiness Logic SQL MAP(Process SQL in

the form of XML)

Full ORM (Hibernate)

Partial ORM (iBatis)

ORM does not use SQL in source code, instead, directly maps java classes to thecolumns of the table or runs and handles SQL in the form of XML


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SQL Map Implementation Code Example

Separate SQL from business logic

Provide simple transaction control (Provide declarative transaction) Provide a familiar SQL-based ORM model

Statement st = null;ResultSet rs = null;try {

st = con.createStatement();StringBuffer query = new StringBuffer();

query.append("\n SELECT A.CHKLST_NO, ");query.append("\n A.EVALFL_CD, ");query.append("\n FROM PR_EVALIT_MB A ");query.append("\n WHERE A.CHKLST_NO = '"

+ sChklstNo + "' ");query.append("\n ORDER BY EVALIT_NOrs = st.executeQuery(st.toString());while(rs.next) {

...}

} finally {try {rs.close();} catch (Exception e) {}try {st.close();} catch (Exception e) {}

}

// ComponentList result =

ISqlManagement.getList (sql.id,value)

// SqlMap.xml

SELECT A.CHKLST_NO, A.EVALFL_CD FROM

PR_EVALIT_MB A WHERE A.CHKLST_NO = #value#ORDER BY EVALIT_NO

Separation of business

logic and SQL

Enhance productivity,maintainability,and reusability,



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MVC (Model, View, Controller) pattern concept

MVC is a software architecture, considered an architectural pattern used in softwareengineering.

The MVC pattern isolates domain logic(the application logic for the user - model ) fromuser interface (input and presentation - view ), then the c ontroller handles the input eventfrom the user interface to process the request through the domain logic.It permits independent development, testing and maintenance of each.Especially, Spring MVC provides DispatcherServlet (*FrontController) that is designed

to implement Presentation layer easier in MVC architecture


DispatcherServlet Controller

Http Request

Http Response

ModelView

[ Conceptual Sequence of MVC pattern with DispatcherServlet ]


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Spring MVC Architecture Composition of eGovFrame

View(JSP)

Controller

Model(BizLogic)

Dispatcher Servlet(Front Controller)

DB

Model andView

HandlerMapping

ViewResolver

Request

Response

Request ContollerRequest

View NameView Response

Model andView

Model andView

Spring's Web MVC framework is designed around a DispatcherServlet thatdispatches requests to handlers, with configurable handler mappings, view

resolution.


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Architecture based on eGovFrame

Presentation Layer Business Layer Data Access Layer

View(JSP)

Dispatcher

Servlet

Controller

Service Interface

ServiceImpl

DAO

DataBase

Request

SQL(XML)

Development Configuration

HandlerMapping

ViewResolver

Spring Config(transaction)

Spring Config(datasource)

Spring Config.

(ORM)

Data Value Object Value Object

Programming Procedure

Spring Module


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02.egovframe training book_overview_supplement_en.pdf

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