2019独角兽企业重金招聘Python工程师标准>>> 
一、理论
类加载时，不进行实例化，调用时才进行类的实例化。
二、代码实现
public class LazyManPattern {
//1.构造方法私有化
private LazyManPattern(){}
//2.类加载时，不进行实例化
private static LazyManPattern lazyManPattern;
//3.创建实例化方法
public static LazyManPattern getLazyManPattern(){
if(lazyManPattern != null){
lazyManPattern = new LazyManPattern();
}
return lazyManPattern;
}
}测试
public class Test {
public static void main(String[] args) {
//----------懒汉设计模式------------
LazyManPattern l1 = LazyManPattern.getLazyManPattern();
LazyManPattern l2 = LazyManPattern.getLazyManPattern();
if(l1 == l2){
System.out.println("l1和l2是相同的。");
}else{
System.out.println("l1和l2不是相同的。");
}
}
}