设计模式（八） 单例设计模式

package com.anby.Singleton;

//为了创建全局唯一的对象，则使用单利模式
public class SingletonDemo
{

/**
* @param args
*/
public static void main(String[] args)
{
SingleA singleA=SingleA.getInstance();

SingleB singleB=SingleB.getInstance();

}

}

// 懒汉式
class SingleA
{
private static SingleA uniqueSingleA;

private SingleA()
{

}

public synchronized static SingleA getInstance()
{
if (uniqueSingleA == null)
{
uniqueSingleA=new SingleA();
}
return uniqueSingleA;
}

}

//饿汉式
class SingleB
{
private static SingleB uniqueSingleB=new SingleB();

private SingleB()
{

}

public synchronized static SingleB getInstance()
{
return uniqueSingleB;
}
}