Why ReflectionChild.class.isInstance(Class.class) is not true?

Question

Why ReflectionChild.class.isInstance(Class.class) is not true?

As we know in reflection Class.class.isInstance(Class.class) is true. Now see on below code snip.

   ReflectionChild ch = new ReflectionChild(); //Take random class

    if(ch.getClass()==ReflectionChild.class){
        System.out.println("ch.getClass()==ReflectionChild.class");
    }

    System.out.println(ReflectionChild.class.getClass());
    System.out.println(Class.class);

    if(ReflectionChild.class.getClass()==Class.class){
        System.out.println("ReflectionChild.class.getClass()==Class.class");
        //System.exit(0);
    }
    if(ReflectionChild.class.isInstance(Class.class)){
        System.out.println("true");
        //System.exit(0);
    }else{
       System.out.println("false");
    }

The output is :-

ch.getClass()==ReflectionChild.class  // 1st SYSOUT

class java.lang.Class                 // 2nd SYSOUT

class java.lang.Class                 // 3rd SYSOUT  

ReflectionChild.class.getClass()==Class.class  //4th SYSOUT

false   // 5th SYSOUT

According to above 1st four SYSOUT's the line ReflectionChild.class.isInstance(Class.class) should be true. But for me it is false as output .

Can any one explain?

Answer 1

Class.class is an instance of Class , not ReflectionChild .
Therefore, isInstance() returns false.

Answer 2

Because a Class instance is not an instance of of type ReflectionChild .

From the javadoc

Specifically, if this Class object represents a declared class, this method returns true if the specified Object argument is an instance of the represented class (or of any of its subclasses); it returns false otherwise.

The argument you've provided is of type Class which is not an instance of the type ReflectionChild represented by the Class instance returned by the class literal expression ReflectionChild.class .

Answer 3

From the Javadocs of Class#isInstance(Object) :

Determines if the specified Object is assignment-compatible with the object represented by this Class . This method is the dynamic equivalent of the Java language instanceof operator. The method returns true if the specified Object argument is non-null and can be cast to the reference type represented by this Class object without raising a ClassCastException . It returns false otherwise.

So the object passed as an argument to the method must be an instance of the class represented by the object on which the method is called, not the other way around : the expression that should return true is the following:

if(Class.class.isInstance(ReflectionChild.class)){