Java Singleton（单例模式）

1.静态类内部加载

 1 /**
 2  * Created by BlueMond on 2018/3/25.
 3  */
 4 public class SingletonModel {
 5     private static class SingletonIn{
 6         public  static SingletonModel special = new SingletonModel();
 7     }
 8     private SingletonModel(){
 9 
10     }
11     public static SingletonModel instance(){ //static very important for the method be found, the SM() is private!!!
12         return SingletonIn.special;
13     }
14 }

2.双重校验锁法

 1 public class SingletonDemo {
 2     private volatile static SingletonDemo instance;
 3     private SingletonDemo(){
 4         System.out.println("Singleton has loaded");
 5     }
 6     public static SingletonDemo getInstance(){
 7         if(instance==null){
 8             synchronized (SingletonDemo.class){
 9                 if(instance==null){
10                     instance=new SingletonDemo();
11                 }
12             }
13         }
14         return instance;
15     }
16 }

 

转载于:https://www.cnblogs.com/cenmny/p/8644938.html