Java设计模式---单例模式

翩跹吉吉

Java设计模式---单例模式
 
1.饿汉式
     
package com.ooad.sington;/** * 饿汉式单例模式 * @author Administrator * */public class Sington1 {private Sington1(){}private static Sington1 sington = new Sington1();public static Sington1 getInstance(){return sington;}} 
 
 
  2.懒汉式（延迟加载）
   
package com.ooad.sington;/* * 懒汉式（延迟加载） */public class Sington2 {private Sington2(){}private static Sington2 sington = null;public static synchronized Sington2 getInstance(){if(sington == null){sington = new Sington2();}return sington;}} 
 
 3.双锁机制（解决懒汉式在高并发量下效率问题）
 
   
package com.ooad.sington;/** * 双锁机制 * @author Administrator * */public class Sington3 {private Sington3(){}private static Sington3 sington = null;public static Sington3 getInstance(){if(sington == null){synchronized(Sington3.class){sington = new Sington3();}}return sington;}}