isAssignableFrom(Class<?> c)

• 標(biāo)識(shí) “當(dāng)前Class 是否是給定的 Class 的超類或者超接口”。是 返回true，否則返回false。
• 標(biāo)識(shí) “當(dāng)前Class 是否與定的 Class 的相同”。是 返回true，否則返回false。
• 如果 “如果該 Class 表示一個(gè)基本類型，且指定的 Class 參數(shù)正是該 Class 對(duì)象”，是則返回true，否則放回false。

demo

        public static void main(String[] args){
        System.out.println(String.class.isAssignableFrom(Object.class));
        System.out.println(Object.class.isAssignableFrom(String.class));

        System.out.println("----------------------------------------");
        System.out.println(int.class.isAssignableFrom(int.class));
        System.out.println(int.class.isAssignableFrom(Object.class));
        System.out.println(Object.class.isAssignableFrom(int.class));
        System.out.println(Integer.class.isAssignableFrom(Object.class));
        System.out.println(Object.class.isAssignableFrom(Integer.class));

        System.out.println("----------------------------------------");

        System.out.println(Person.class.isAssignableFrom(Object.class));
        System.out.println(Object.class.isAssignableFrom(Person.class));
        System.out.println(Person.class.isAssignableFrom(Person.class));
        System.out.println(Person.class.isAssignableFrom(Serializable.class));
        System.out.println(Serializable.class.isAssignableFrom(Person.class));
        System.out.println(Person.class.isAssignableFrom(SuperA.class));
        System.out.println(SuperA.class.isAssignableFrom(Person.class));

        System.out.println("----------------------------------------");

        System.out.println(List.class.isAssignableFrom(ArrayList.class));
        System.out.println(ArrayList.class.isAssignableFrom(List.class));
    }

    class Person implements Serializable, A{}

    interface A extends SuperA{}

    interface SuperA{}

log

false
true
======================
true
false
false
false
true
======================
false
true
true
false
true
false
true
=======================
true
false