模拟“事件监听器”（二）

1、定义一个事件类

package hb.event;public class Event {private EventType type;    private int nodeID;    private boolean processed;    public Event(EventType type, int oldNodeID) {        this.type = type;        this.nodeID = oldNodeID;    }    public EventType getType() {        return type;    }    public int getNodeID() {return nodeID;}public void setNodeID(int nodeID) {this.nodeID = nodeID;}public void setType(EventType type) {this.type = type;}public boolean isProcessed() {        return processed;    }    public void setProcessed(boolean processed) {        this.processed = processed;    }    @Overridepublic String toString() {        return super.toString() + " type: " + type;    }        public static enum EventType {        /**         * This JVM joined a cluster.         */        receive,        /**         * This JVM is no longer part of the cluster.         */        send,    }}

 

2、定义一个监听接口

package hb.event;public interface EventListener {public void action(Event event);}

 

3、添加两个监听接口实现类

package hb.event;public class ReceiveEventListener implements EventListener {private Event event;@Overridepublic void action(Event event) {// TODO Auto-generated method stubSystem.out.println("ReceiveEventListener");}public ReceiveEventListener(Event event){this.event = event;}public ReceiveEventListener(){}}

 

package hb.event;public class SendEventListener implements EventListener {private Event event;@Overridepublic void action(Event event) {// TODO Auto-generated method stubSystem.out.println("SendEventListener");}public SendEventListener(Event event) {this.event = event;}public SendEventListener() {}}

 

4、定义一个事件源（即监听事件的目标）

package hb.event;import java.util.HashMap;import java.util.Map;public class Resource {Map<Event.EventType,EventListener> map = new HashMap<Event.EventType,EventListener>();public void addListener(Event.EventType eventType,EventListener eventListener){map.put(eventType, eventListener);}public void removeListener(Event.EventType eventType){map.remove(eventType);}public void sendAction(Event event){EventListener eventListener = (EventListener)map.get(Event.EventType.send);if(eventListener!=null){eventListener.action(event);}}public void receiveAction(Event event){EventListener eventListener = (EventListener)map.get(Event.EventType.receive);if(eventListener!=null){eventListener.action(event);}}}

 

5、测试类

package hb.event;public class EventTest {public static void main(String[] args) {Resource resource = new Resource();ReceiveEventListener receiveListener = new ReceiveEventListener();SendEventListener sendListener = new SendEventListener();resource.addListener(Event.EventType.receive, sendListener);resource.addListener(Event.EventType.send, sendListener);Event sendevent = new Event(Event.EventType.send,1);Event receiveevent = new Event(Event.EventType.receive,2);resource.sendAction(sendevent);resource.receiveAction(receiveevent);}}