二元操作符,当左边的对象是右边类或子类所创建对象时,返回true;否则,返回false。
class A { } class B extends A { } public class Test { public static void main(String[] args) { A a = new A(); B b = new B(); System.out.println(a instanceof B);// false System.out.println(a instanceof A);// true System.out.println(b instanceof A);// true } }