Re: How to pass a class as argument?

From:

Lew <lew@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 16 Jun 2010 12:00:20 -0700 (PDT)

Message-ID:

<fbb130fd-990f-4336-9e66-c81c01022cbf@a29g2000vbl.googlegroups.com>

Krishna K wrote:

Thanks for the reply, they are not in the same package, 'B' wouldn't
know the package name of 'A', thus it wouldn't know the type of 'that
Class', the point is for 'A' to pass that information so the module in
'B' can us e that information.- Hide quoted text -

Sounds like a bad design is operating here.

See the advice elsethread to supply an SSCCE.

The method in 'B' should have an argument that specifies the expected
type. The nested class of 'A' should inherit that type. Perhaps
generics would help.

public class A
{
  public static class Foo implements Usable
  {
    @Override // override Usable#whatever()
    public Bar whatever()
    {
      Bar retval = obtainBar(); // your logic here
      return retval;
    }
  }
  public void doSomething()
  {
     B helper = new B();
     Foo foo = new Foo();
     helper.helpMe( foo );
     // ... etc.
  }
}

public class B
{
  public void helpMe( Usable foo )
  {
    // ... etc.
  }
}

Forget reflection and use of Class<T> if you can help it.

--
Lew