Spring中ApplicationEvent和ApplicationListener封装

1.测试程序EventTest.java，发布一个事件只需要调用FrameEventHolder.publishEvent()方法即可。

package com.junge.spring.event;

import com.junge.spring.vo.Mail;

public class EventTest {

    /**
     * @param args
     */
    public static void main(String[] args) {
        FrameEvent frameEvent = new FrameEvent();

        Mail mail = new Mail();
        mail.setContent("accdddount");
        mail.setEmail("333@email.com");

        frameEvent.setPrameter(mail);
        frameEvent.setEventId("send_mail_notify");
        frameEvent.setSync(false);

        FrameEventHolder.publishEvent(frameEvent);
    }

}

2.应用上下文保持器ContextHolder.java

/**
 * 
 */
package com.junge.spring.context;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * @author Administrator
 * 
 */
public class ContextHolder {

    private static ApplicationContext context = null;

    static {
        context = new ClassPathXmlApplicationContext("event.xml");
    }

    public static ApplicationContext getApplicationContext() {
        return context;
    }
}

3.事件类FrameEvent.java，继承自Spring的ApplicationEvent，可以保持事件处理参数

/**
 * 
 */
package com.junge.spring.event;

import org.springframework.context.ApplicationEvent;

/**
 * @author Administrator
 * 
 */
public class FrameEvent extends ApplicationEvent {

    private static final long serialVersionUID = 1L;

    /**
     * 保持事件业务参数
     */
    private Object prameter;

    /**
     * 一类事件编号
     */
    private String eventId;

    public FrameEvent() {
        super("source");
    }

    public FrameEvent(Object source) {
        super(source);
    }

    public Object getPrameter() {
        return prameter;
    }

    public void setPrameter(Object prameter) {
        this.prameter = prameter;
    }

    public String getEventId() {
        return eventId;
    }

    public void setEventId(String eventId) {
        this.eventId = eventId;
    }

}

4.发布事件静态方法 FrameEventHolder.java

package com.junge.spring.event;

import org.springframework.util.Assert;

import com.junge.spring.context.ContextHolder;

public class FrameEventHolder {

	public static void publishEvent(FrameEvent frameEvent) {

		Assert.notNull(frameEvent);

		ContextHolder.getApplicationContext().publishEvent(frameEvent);
	}

}

 5.事件处理接口EventHandler.java

package com.junge.spring.event.handler;

public interface EventHandler {

    /**
     * 获取事件ID
     */
    String getEventId();

    /**
     * 处理事件入口
     * 
     * @param parameter
     */
    void handle(Object parameter);

}

6.事件处理接口抽象类FrameEventHandler.java，业务事件处理从该类继承

/**
 * 
 */
package com.junge.spring.event.handler;

/**
 * @author Administrator
 * 
 */
public abstract class FrameEventHandler implements EventHandler {

    private String eventId;

    /**
     * @param eventId
     *            the eventId to set
     */
    public void setEventId(String eventId) {
        this.eventId = eventId;
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.junge.spring.event.listener.EventHandler#getEventId()
     */
    @Override
    public String getEventId() {

        return eventId;
    }
}

7.业务事件处理实现MailEventHandler.java，从FrameEventHandler.java继承，实现handle方法

/**
 * 
 */
package com.junge.spring.event.handler;

import com.junge.spring.vo.Mail;

/**
 * @author Administrator
 * 
 */
public class MailEventHandler extends FrameEventHandler {

    @Override
    public void handle(Object parameter) {
        if (null != parameter) {
            Mail mail = (Mail) parameter;
            System.out.println("需要发送邮件给" + mail.getEmail() + "，邮件内容是:"
                    + mail.getContent());
        }

    }

}

8.事件监听器FrameEventListener.java，调用事件业务处理逻辑（即调用handle方法）

/**
 * 
 */
package com.junge.spring.event.listener;

import org.springframework.context.ApplicationListener;

import com.junge.spring.event.FrameEvent;
import com.junge.spring.event.handler.EventHandler;

/**
 * @author Administrator
 * 
 */
public class FrameEventListener implements ApplicationListener<FrameEvent> {

    private EventHandler eventHandler;

    @Override
    public void onApplicationEvent(FrameEvent event) {

        if (eventHandler.getEventId().equals(event.getEventId())) {
            eventHandler.handle(event.getPrameter());
        }
    }

    public EventHandler getEventHandler() {
        return eventHandler;
    }

    public void setEventHandler(EventHandler eventHandler) {
        this.eventHandler = eventHandler;
    }

}

9.业务VO对象Mail.java

/**
 * 
 */
package com.junge.spring.vo;

/**
 * @author Administrator
 *
 */
public class Mail {
    private String email;
    
    private String content;

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }
}

10.Spring业务配置文件event.xml

<?xml version="1.0" encoding="UTF-8"?>
<p:beans xmlns:p="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans spring-beans-3.2.xsd ">

    <p:bean id="mailHandler" class="com.junge.spring.event.handler.MailEventHandler">
        <p:property name="eventId" value="send_mail_notify" />
    </p:bean>

    <p:bean id="mailListener" class="com.junge.spring.event.listener.FrameEventListener">
        <p:property name="eventHandler" ref="mailHandler" />
    </p:bean>
</p:beans>

11.测试结果

2015-1-23 14:23:17 org.springframework.context.support.AbstractApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@2808b3: startup date [Fri Jan 23 14:23:17 CST 2015]; root of context hierarchy
2015-1-23 14:23:18 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [event.xml]
2015-1-23 14:23:19 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@db4fa2: defining beans [mailHandler,mailListener]; root of factory hierarchy
需要发送邮件给333@email.com，邮件内容是:accdddount