//instanceof关键字用于判断一个引用类型变量所指向的对象是否是一个类(或接口、抽象类、父类)的实例
if(new Date() instanceof Date) {
System.out.println("yes1");
}
if(new Date() instanceof Comparable) {
System.out.println("yes2");
}
if(new SimpleDateFormat() instanceof DateFormat) {
System.out.println("yes3");
}
String [] arr = {"34","23","12"};
if(arr instanceof String []) {
System.out.println("yes4");
}
//结果
yes1
yes2
yes3
yes4