Java getConstructor(types) with parametised types

Question

If I have a class with a constructor that takes a parametized generic type:

public class Foo {
    public Foo(Map<String, Object> data) {
      ...
    }
}

... how do I reference that parametized Map's class if I want to call:

Constructor constructor = cls.getConstructor(/*the Map class! */)

(Where cls is the Foo class.)

I want to do something like:

Constructor constructor = cls.getConstructor(Map<String,Object>.class);

... but that doesn't work.

I'm sure there's a simple answer to this!

Answer 1

At runtime, this:

  Map<String,Object>

Is actually just a Map, without any parameters.

Calling

 cls.getConstructor(Map.class) will be enough

Answer 2

You can reference the constructor by just the Map type. The generic parameters are erased for runtime:

Constructor constructor = Foo.class.getConstructor(Map.class);