深入浅出Spring事件机制

事件实现依赖ApplicationEvent抽象类和ApplicationListener接口,applicationContext发布（publishEvent）了事件以后，ApplicationListener的onApplicationEvent监听之： 
Java代码如下 ： 

01	package com.uqee.spring.applicationContext;

02

03	import org.apache.commons.logging.Log;

04	import org.apache.commons.logging.LogFactory;

05	import org.springframework.context.ApplicationEvent;

06

07	public class EmailEvent extends ApplicationEvent

08

{

09	private String address;

10	private String text;

11	private String email;

12	public String getEmail()

13

{

14	return email;

15

}

16

17	public void setEmail(String email)

18

{

19	this.email = email;

20

}

21

22	private Log logger = LogFactory.getLog(EmailEvent.class);

23

24	public EmailEvent(Object source)

25

{

26	super(source);

27	// TODO Auto-generated constructor stub

28

}

29

30	public EmailEvent(String email,String address,String text)

31

{

32	super(email);

33	this.email = email;

34	this.address = address;

35	this.text = text;

36

}

37

38	public void printInfo()

39

{

40	//      System.out.println("Send this Email, address:"+address+" text:");

41	logger.info("Send this Email, address:"+address+" text:"+text);

42

}

43

44

/**

45

*

46

*/

47	private static final long serialVersionUID = 1667085258090884727L;

48

49

}

01	package com.uqee.spring.applicationContext;

02

03	import org.springframework.context.ApplicationEvent;

04	import org.springframework.context.ApplicationListener;

05

06	public class EmailNotifier implements ApplicationListener

07

{

08

09	private String notificationAddress;

10

11

12	public String getNotificationAddress()

13

{

14	return notificationAddress;

15

}

16

17

18	public void setNotificationAddress(String notificationAddress)

19

{

20	this.notificationAddress = notificationAddress;

21

}

22

23

24

@Override

25	public void onApplicationEvent(ApplicationEvent event)

26

{

27	// TODO Auto-generated method stub

28	if(event instanceof EmailEvent)

29

{

30	//notifier apppriate person

31	EmailEvent emailEvent = (EmailEvent)event;

32	System.out.println("我已收到通知："+emailEvent.getEmail()+"要发邮件了。。");

33

}

34

}

35

36

}

01	package com.uqee.spring.applicationContext;

02

03	import java.util.List;

04

05	import org.springframework.beans.BeansException;

06	import org.springframework.context.ApplicationContext;

07	import org.springframework.context.ApplicationContextAware;

08

09	public class EmailBean implements ApplicationContextAware

10

{

11

12	private ApplicationContext ctx = null;

13	public ApplicationContext getCtx()

14

{

15	return ctx;

16

}

17

18	private List backList;

19

20	public List getBackList()

21

{

22	return backList;

23

}

24

25	public void setBackList(List backList)

26

{

27	this.backList = backList;

28

}

29

30

@Override

31	public void setApplicationContext(ApplicationContext applicationContext)

32	throws BeansException

33

{

34	// TODO Auto-generated method stub

35	this.ctx = applicationContext;

36

}

37

38	public void sendEmail(String email,String title,String text)

39

{

40	if(backList.contains(email))

41

{

42	EmailEvent evt = new EmailEvent(email,title, text);

43	ctx.publishEvent(evt);

44

return ;

45

}

46

}

47

}

xml配置如下 ： 

01	<bean id="emailer" class="com.uqee.spring.applicationContext.EmailBean">

02	<property name="backList">

03

<list>

04	<value>[email protected]</value>

05	<value>[email protected]</value>

06	<value>[email protected]</value>

07

</list>

08	</property>

09

</bean>

10

11	<bean id="emailNotifier" class="com.uqee.spring.applicationContext.EmailNotifier">

12	<property name="notificationAddress">

13	<value>[email protected]</value>

14	</property>

15

</bean>

测试类如下 ： 

view source

print ?

1	ApplicationContext applicationContext = newClassPathXmlApplicationContext("applicationContext5.xml");

2	EmailBean emailer = (EmailBean)applicationContext.getBean("emailer");

3	emailer.sendEmail("[email protected]", "邮件头", "邮件正文");

打印结果如下： 
我已收到通知：[email protected]要发邮件了。。