1 package observer;2 //接口，用以实现小孩醒来时要做的事3 public interface IWakeupListener {4 5     public void ActionToWakeup(WakeupEvent eve);6 }

1 package observer;2 //Dad实现喂奶的动作3 public class Dad  implements IWakeupListener{4     @Override5     public void ActionToWakeup(WakeupEvent e) {6         System.out.println("儿子醒了，我要去喂奶了。。。");7     }8 }

 1 package observer; 2 //狗实现叫的动作 3 public class Dog implements IWakeupListener { 4  5     @Override 6     public void ActionToWakeup(WakeupEvent e) { 7         System.out.println("小主人醒了，我就汪汪叫。。。"); 8     } 9 10 }

1 package observer;2 //爷爷实现抱的动作3 public class GrandFather implements IWakeupListener{4 5     @Override6     public void ActionToWakeup(WakeupEvent e) {7         System.out.println("小孙子醒了，我要去抱抱！！！");8     }9 }

 1 package observer; 2 //小孩的醒来事件:醒来时间，醒来地点，醒来的是谁 3 public class WakeupEvent { 4     private long time; 5     private String location; 6     private Child sorce; 7      8      9     public WakeupEvent(long time, String location, Child sorce) {10         super();11         this.time = time;12         this.location = location;13         this.sorce = sorce;14     }15     public long getTime() {16         return time;17     }18     public void setTime(long time) {19         this.time = time;20     }21     public String getLocation() {22         return location;23     }24     public void setLocation(String location) {25         this.location = location;26     }27     public Child getSorce() {28         return sorce;29     }30     public void setSorce(Child sorce) {31         this.sorce = sorce;32     }33 }

 1 package observer; 2 //小孩 3 import java.util.ArrayList; 4 import java.util.Iterator; 5 import java.util.List; 6  7 public class Child implements Runnable{ 8  9     private List<IWakeupListener> listener = new ArrayList<IWakeupListener>();10     11     public void addWakeupListener(IWakeupListener l)12     {13         listener.add(l);14     }15     16 //-------------测试17     @Override18     public void run() {19         try {20             Thread.sleep(3000);21         } catch (InterruptedException e) {22             // TODO Auto-generated catch block23             e.printStackTrace();24         }25         wakeup();26     }27 28     private void wakeup() {29 //        Iterator<IWakeupListener> iter = listener.iterator();30 //        while (iter.hasNext()) {31 //            IWakeupListener l = iter.next();32 //        }33         34         for(Iterator<IWakeupListener> iter = listener.iterator();iter.hasNext();)35         {36             IWakeupListener l = iter.next();37             l.ActionToWakeup(new WakeupEvent(System.currentTimeMillis(), "home", this));38         }39         40     }41 //-------------测试end42 43 }

配置文件：observer.properties，放在asset/config文件夹下
1 observers=observer.Dad;observer.GrandFather;observer.Dog

 1 package observer; 2 //解析.properties 3 import java.io.IOException; 4 import java.util.Properties; 5  6 public class PropertyProxy { 7  8     private Properties properties = new Properties(); 9     private static PropertyProxy instance=null;10     public static PropertyProxy Instance()11     {12         if(instance==null)13         {14             instance = new PropertyProxy();15         }16         return instance;17     }18     19     public String getProperty(String path,String key)20     {21         try {22             properties.load(PropertyProxy.class.getClassLoader().getResourceAsStream(path));23         } catch (IOException e) {24             // TODO Auto-generated catch block25             e.printStackTrace();26         }27         28         return properties.getProperty(key);29     }30 }

 1 package observer; 2  3 import java.util.ArrayList; 4 import java.util.Iterator; 5 import java.util.List; 6  7 public class Child implements Runnable{ 8  9     private List<IWakeupListener> listener = new ArrayList<IWakeupListener>();10     11     public void addWakeupListener(IWakeupListener l)12     {13         listener.add(l);14     }15     16 //-------------测试17     @Override18     public void run() {19         try {20             Thread.sleep(3000);21         } catch (InterruptedException e) {22             // TODO Auto-generated catch block23             e.printStackTrace();24         }25         wakeup();26     }27 28     private void wakeup() {29 //        Iterator<IWakeupListener> iter = listener.iterator();30 //        while (iter.hasNext()) {31 //            IWakeupListener l = iter.next();32 //        }33         34         for(Iterator<IWakeupListener> iter = listener.iterator();iter.hasNext();)35         {36             IWakeupListener l = iter.next();37             l.ActionToWakeup(new WakeupEvent(System.currentTimeMillis(), "home", this));38         }39         40     }41 //-------------测试end42 43 }

 1 package observer; 2  3 import oracle.net.aso.c; 4  5 public class Test { 6  7     public static void main(String[] args) { 8         Child child = new Child(); 9         10         String[] observerArr = PropertyProxy.Instance().getProperty("asset/config/observer.properties", "observers").split(";");11         12         for(String className: observerArr)13         {14             IWakeupListener l = null;15             try {16                 l = (IWakeupListener)(Class.forName(className).newInstance());17             } catch (InstantiationException | IllegalAccessException18                     | ClassNotFoundException e) {19                 e.printStackTrace();20             }21             child.addWakeupListener(l);22         }23         24         new Thread(child).start();25     }26 }