谁来帮帮我,JAVA问题
来源:百度知道 编辑:UC知道 时间:2024/05/14 07:32:05
public class Singleton {
private static Singleton instance = null;
public static synchronized Singleton getInstance() {
if (instance==null)
instance=new Singleton();
return instance; }
}
public class SingletonPattern
{
private double r;
//定义一个私有,静态的引用变量
private static SingletonPattern sp;
//构造器私有
private SingletonPattern()
{
r = java.lang.Math.random();
}
//提供一个共有,静态方法获得唯一实例
public static SingletonPattern getInstance()
{
if(sp==null)//如果还未创建实例
{
sp = new SingletonPattern();
}
return sp;
}
public double getR()
{
return r;
}
public static void main(String args[])
{
SingletonPattern sp1 =
SingletonPattern.getInstance();
SingletonPattern sp2 =<