单例设计模式

package class1;
//单例设计模式
class Singleton {
private static Singleton instance = new Singleton();
private Singleton(){}
public void print() {
System.out.println("Hello World!!!");
}
public static Singleton getInstance() {
return instance;
}
}
public class SingleDemo04 {
public static void main(String args[]) {
Singleton s1 = Singleton.getInstance();
s1.print();
}
}