Question

I have the following code:

class SuperClass {     public static String getName() { return 'super'; } }  class SubClass extends SuperClass {     public static String getName() { return 'sub'; } }  public class Dummy<T extends SuperClass> {     public void print() {         System.out.println('SuperClass: ' + SuperClass.getName());         System.out.println('SubClass: ' + SubClass.getName());         System.out.println('T: ' + T.getName());     }     public static void main(String[] args) {         new Dummy<SubClass>().print();     } } 

This code outputs the following:

SuperClass: super SubClass: sub T: super 

My question is: Why doesn’t T.getName() return the value of SubClass.getName()? After all, I specified that T == SubClass. Or are static function calls invalid for generic references?

Thanks a lot in advance!

Answer 1

This isn’t just an issue about generics.

If you say:

SuperClass obj = new SubClass(); System.out.println(obj.getName()); 

you will also get ‘super’. There are no ‘polymorphic’ static methods.

In your case, all the compiler knows about T is that it extends SuperClass, so it will call SuperClass.getName().