public class Singleton{
  private Singleton(){}
  private static Singleton instance= new Singleton();
  public static Singleton getInstance(){
    return instance;
  }
}

安全的一种写法

publict class Singleton{

  private static Singleton instance =null;

  public static synchronized Singleton getInstance(){

  if(instance==null)

  instance=new Singleton();

     return instance;  

  

}

}

 

posted on 2017-05-05 19:07  wang_ya_fei  阅读(199)  评论(0编辑  收藏  举报