instanceof

来源：互联网发布：linux转发工具编辑：程序博客网时间：2024/05/22 07:06

interface A{}class B implements A{}class C extends B{}public class Iinstanceof {    public static void main(String[] args) {        A ab=new B();        A ac=new C();        B bc=new C();        B bb=new B();        C cc=new C();        //对象实现一个接口，用这个对象和这个接口进行instanceof判断，都为true。        System.out.println("ab instanceof A="+(ab instanceof A));        System.out.println("ac instanceof A="+(ac instanceof A));        System.out.println("bc instanceof A="+(bc instanceof A));        System.out.println("bb instanceof A="+(bb instanceof A));        System.out.println("cc instanceof A="+(cc instanceof A));        //对象和父类进行instanceof判断，都为true        System.out.println("ab instanceof B="+(ab instanceof B));        System.out.println("ac instanceof B="+(ac instanceof B));        System.out.println("bc instanceof B="+(bc instanceof B));        System.out.println("bb instanceof B="+(bb instanceof B));        System.out.println("cc instanceof B="+(cc instanceof B));        //对象和他的子类进行instanceof判断        System.out.println("ab instanceof C="+(ab instanceof C));        System.out.println("ac instanceof C="+(ac instanceof C));        System.out.println("bc instanceof C="+(bc instanceof C));        System.out.println("bb instanceof C="+(bb instanceof C));        System.out.println("cc instanceof C="+(cc instanceof C));    }}

输出：

ab instanceof A=true ac instanceof A=true bc instanceof A=true bb instanceof A=true cc instanceof A=true ab instanceof B=true ac instanceof B=true bc instanceof B=true bb instanceof B=true cc instanceof B=true ab instanceof C=false ac instanceof C=true bc instanceof C=true bb instanceof C=false cc instanceof C=true

0 0