Java-马士兵设计模式学习笔记-观察者模式-读取properties文件改成单例模式

一、概述

1.目标：读取properties文件改成单例模式

二、代码

1.Test.java

 class WakenUpEvent{

     private long time;
     private String location;
     private Child source;

     public WakenUpEvent(long time, String location, Child source) {
         super();
         this.time = time;
         this.location = location;
         this.source = source;
     }

     public long getTime() {
         return time;
     }

     public void setTime(long time) {
         this.time = time;
     }

     public String getLocation() {
         return location;
     }

     public void setLocation(String location) {
         this.location = location;
     }

     public Child getSource() {
         return source;
     }

     public void setSource(Child source) {
         this.source = source;
     }

 }

 class Child implements Runnable {

     private List<WakenUpListener> wakenUpListeners = new ArrayList<WakenUpListener>();

     public void addWakenUpListener(WakenUpListener wul){
         wakenUpListeners.add(wul);
     }
     public void wakeUp(){
         for(int i = 0; i < wakenUpListeners.size(); i++){
             WakenUpListener l = wakenUpListeners.get(i);
             l.actionToWakenUp(new WakenUpEvent(System.currentTimeMillis(), "bed", this));
         }
     }

     @Override
     public void run() {
         try {
             Thread.sleep(3000);
         } catch (Exception e) {
             e.printStackTrace();
         }
         wakeUp();
     }
 }

 interface WakenUpListener {
     public void actionToWakenUp(WakenUpEvent e);
 }

 class Dad implements WakenUpListener {

     public void actionToWakenUp(WakenUpEvent e) {
         System.out.println("Fedd the child");
     }

 }

 class GrandFather implements WakenUpListener {

     public void actionToWakenUp(WakenUpEvent e) {
         System.out.println("抱孩子");
     }

 }

 class PropertiesMgr{

     private static Properties props = new Properties();

     //只加载一次，但如果properties有更新，它不会反馈
     static {
         try {
             props.load(Test.class.getClassLoader().getResourceAsStream("com/tong/observer/observer.properties"));
         } catch (Exception e) {
             e.printStackTrace();
         }
     }

     public static String getProperty(String key){
         return  props.getProperty(key);
     }
 }
 public class Test {

     public static void main(String[] args) {

         Child c = new Child();

         String [] observers = PropertiesMgr.getProperty("observers").split(",");

         for(String s : observers){
             try {
                 c.addWakenUpListener((WakenUpListener)Class.forName(s).newInstance());
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
         new Thread(c).start();
     }
 }

三、运行结果