java 单例模式

/*单例模式类*/

package com.test.cn;


public class Singleton {


private Singleton(){}
private int para1;
public int getPara1() {
return para1;
}


public void setPara1(int para1) {
this.para1 = para1;
}
public static Singleton single= null;

public static Singleton getInnstance()
{
if(single == null)
{
single = new Singleton();
}
return single;
}

}

/*测试类*/

package com.test.cn;


public class test1 {


public static void main(String[] args) {
// TODO Auto-generated method stub
Singleton single = Singleton.getInnstance();
Singleton single1=Singleton.getInnstance();
single.setPara1(10);
System.out.println("single="+single.getPara1());
System.out.println("single1="+single1.getPara1());
return ;
}


}

最后打印结果是，single1 对象未做赋值，结果打印的也是10，所以single与single1 为同一对象