java 用volatile实现一个双重检查锁的单例模式

Posted 2021-05-08

public class Singleton{
	private static volatile Singleton singleton ;
	private Singleton(){}
	public static Singleton getInstance(){
		if(singleton == null){
			synchronize(Singleton.class){
			  if(singleton == null){
			    singleton = new Singleton();
			  }
			}
		}
		return singleton ;
	}
	
}