Spring DI

Inversion of Control?Dependency Injection?Spring - DI

Interface Hello World! Hi World! .

Rendering .Spring - DI

Spring - DI

Spring - DI

Hello World! Hi World!! World! .

Rendering .

Name .Spring - DI

?Spring - DI

Factory PatternSpring - DI

Spring - DIFactory Pattern

SpringSpring - DI

How?Spring - DI

Metadata(XML Property)Spring Framework(ApplicationContext)Spring - DI

Spring Spring - DI

package spring;

import old.MessageRenderer;

import org.springframework.beans.factory.BeanFactory;import org.springframework.beans.factory.xml.XmlBeanFactory;import org.springframework.core.io.FileSystemResource;

public class DefaultMessageRendererWithSpringTest{

public static void main(String[] args) {BeanFactory beanFactory = new XmlBeanFactory(new FileSystemResource("conf/spring.xml"));MessageRenderer renderer = (MessageRenderer) beanFactory.getBean("renderer");

renderer.render();}

}Spring Spring - DI

Inversion of Control(IoC)Spring - DI

IoCDIIoC : Inversion of ControlDI : Dependency InjectionDP : Dependency PullDPConstructor InjSetter Inj EJB Spring Spring PicoContainerMethod InjSpring - DI

Spring . Spring , IoC ?

? Spring - DI

Servlet Container Servlet , , , Servlet . Servlet . JSP/Servlet , .

Servlet ContainerServlet AServlet BServlet CServlet DCreateInitServiceDestorySpring - DI

EJB Container EJB(, , MDB) , , , EJB . EJB .Transaction, Security, EJB Pooling .

EJB ContainerEJB AEJB BEJB CEJB DCreateInitServiceDestorySpring - DI

IoC( DI) ContainerPOJO , , POJO . POJO , Container .Transaction, Security . AOP Container .

IoC( DI) ContainerPOJO APOJO BPOJO CPOJO DCreateInitServiceDestorySpring - DI

POJO(Plain Old Java Object) ?Martin Fowler: http://www.martinfowler.com/bliki/POJO.html

Servlet EJB Interface(Contracts) .

POJO .

Spring - DI

Singleton?, Non Singleton?Spring - DI

Singleton Pattern SingletonSpring - DI

public class MessageService { private static MessageService instance;

private MessageService() {}

public static MessageService getInstance() { if(instance == null ) { instance = new MessageService(); } return instance; }}

Singleton Spring - DI

public class MessageProviderFactory { public static final int HI_WORLD_PROVIDER = 0; public static final int HELLO_WORLD_PROVIDER = 1; public static final int ANNYOUNG_WORLD_PROVIDER = 2; private static final Map providers = new HashMap (); static { providers.put(HI_WORLD_PROVIDER, new HiworldMessageProvider()); providers.put(HELLO_WORLD_PROVIDER, new HelloworldMessageProvider()); providers.put(ANNYOUNG_WORLD_PROVIDER, new AnnyoungworldMessageProvider()); } public static MessageProvider getMessageProvider(int status) { return providers.get(status); }}

MessageProviderFactory SingletonSpring - DI

Spring SingletonSpring - DI

ApplicationContextrenderer "" hiWorldMessageProvider(key)(value)DefaultMessageRenderer HiWorldMessageProvider

Spring - DIServletContext(sigle instance)org.springframework.web.context. WebApplicationContext.ROOT"(key)(value)WebApplicationContext JVM

Spring - DI

Spring 2.0 ScopeSpring - DI

Singleton Spring - DI

public class Person {private String name;

public void setName(String name) {this.name = name;}

public String getName() {return name;}} Thread AThread Bnew Person();new Person();name = nullSingleton InstanceSpring - DI

public class Person {private String name;

public void setName(String name) {this.name = name;}

public String getName() {return name;}} Thread Aperson.setName();name = Singleton InstanceSpring - DI

public class Person {private String name;

public void setName(String name) {this.name = name;}

public String getName() {return name;}} person.setName();name = Thread BSingleton InstanceSpring - DI

public class Person {private String name;

public void setName(String name) {this.name = name;}

public String getName() {return name;}} Thread Aperson.getName(); => name = Singleton InstanceSpring - DI

Static Singleton Dependency .

Singleton Configuration .

interface-unfriendly => Test .

.

Runtime Singleton .

OOP .Spring - DI

Spring

new

Factory method

FactoryBean Interface

ApplicationContext context = new ClassPathXmlApplicationContext(paths);UserService userService = context.getBean(userService);

loggingAdvice emailNotificationThrowsAdvice

ApplicationContext context = new ClassPathXmlApplicationContext(paths);ProxyFactoryBean factoryBean = context.getBean(userService);

loggingAdvice emailNotificationThrowsAdvice

ApplicationContext context = new ClassPathXmlApplicationContext(paths);UserService userService = context.getBean(userService);

java:comp/env/jdbc/petclinic

ApplicationContext context = new ClassPathXmlApplicationContext(paths);JndiObjectFactoryBean factoryBean = context.getBean(dataSource);

java:comp/env/jdbc/petclinic

ApplicationContext context = new ClassPathXmlApplicationContext(paths);DataSource dataSource = (DataSource)context.getBean(dataSource);

Spring FriendsSingleton PatternStrategy PatternFactory PatternObserver PatternTemplate Method PatternSpring - DI

JVM http://hjbang.snut.ac.kr/data/java2005/JAVA06.ppt

http://saloon.javaranch.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=1&t=012143Spring - DI

1. Invoke2. 3. setXXX() 4. setBeanName() 5. setBeanFactory() 6. setApplicationContext() 7. afterProperties() 8. init-method POJO POJO POJO 9. destroy() 10. destory-method Spring - DI

POJO InitializingBean, DisposableBean Spring , 123 126 http://wiki.javajigi.net/pages/viewpage.action?pageId=1040 Spring - DI

ApplicationContext BeanNameAware, BeanFactoryAware, ApplicationContextAware

http://wiki.javajigi.net/pages/viewpage.action?pageId=1101Spring - DI

Spring - DI

Why DI?Easy TestDependency Spring - DI