Check if a type is an interface

Question

I want to validate a parameter sent to a method, it must be an interface type. What to ask?

void (Class interfaceType){
  if (thisisnotaninterface){         


        

Answer 1

You have got a Class#isInterface() method that does exactly what you want: -

if (!interfaceType.isInterface()) {
    throw...
}

Answer 2

For a normal java object you can always use instanceof.

If Test implements Testable

Test test = new Test();

test instanceof Testable will be true

Answer 3

Just use Class#isInterface() to check that

And seriously, you should be reading the Javadocs before asking here.