java instanceof ?????????

Posted 2021-02-14

tags:

篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了java instanceof ?????????相关的知识，希望对你有一定的参考价值。

?????????span ?????? ?????? ?????? ?????? ?????? ?????? ????????? pre

???????????????java ??????instanceof ??????????????????????????????????????????????????????????????????????????????instanceof??????????????????????????????????????????????????????????????????????????????????????????????????????????????????

?????????
result = object instanceof class
?????????
Result??????????????????
Object???????????????????????????????????????
Class?????????????????????????????????????????????
?????????
?????? object ??? class ????????????????????? instanceof ??????????????? true????????? object ??????????????????????????????????????? object ??? null???????????? false???

??????instanceof???Java????????????????????????????????????????????????

?????????????????????class?????????object????????????????????????????????????????????????????????????Java????????????????????????

?????????????????????class?????????object?????????????????????????????????????????????????????????????????????result????????????true??????????????????false?????????class????????????????????????????????????????????????false???

???????????????????????????

 interface Person {
    public void eat();
}

//?????????People

 class People implements Person {
    private int a=0;
    @Override
    public void eat() {
        System.out.println("======"+a);

    }

}

//??????xiaoming???

 class xiaoming extends People {
    private String name;

    @Override
    public void eat() {
        System.out.println("+++++++++");
    }
}

//?????????
class  Test {
    public static void main(String[] args) {
        People p = new People();
        xiaoming x = new xiaoming();
        System.out.println(p instanceof Person);
        System.out.println(p instanceof xiaoming);
        System.out.println(x instanceof Person);
        System.out.println(x instanceof People);


    }
}

???????????????

true
false
true
true

以上是关于java instanceof ?????????的主要内容，如果未能解决你的问题，请参考以下文章