Java Reflection class not found problem

[andrea casini]

Hello to everyone.

I am experiencing a really annoying problem when using reflection. I have this simple code:

   class A {}

   public class instance1 {
      public static void main(String args[])
      {
         try {
            Class cls = Class.forName("A");
            boolean b1 
              = cls.isInstance(new Integer(37));
            System.out.println(b1);
            boolean b2 = cls.isInstance(new A());
            System.out.println(b2);
         }
         catch (Throwable e) {
            System.err.println(e);
         }
      }
   }

I took this example from the official guide but when I run this in Netbeans 6.9.1 it return a "ClassNotFoundException".. WTF the class A is there!! Why is this happen?
I believe it has something to do with netbeans.

Please help.

Thanks

[Markas Korotkovas]

are you using default package? if not you need to specify fully qualified name for A when doing the Class.forName("...")

[andrea casini]

Markas Korotkovas wrote:are you using default package? if not you need to specify fully qualified name for A when doing the Class.forName("...")

Ok.. The class is in "build/classes/model/". But I don't know the sintax to specify the classpath in the "forName" method. Could you please tell me how?

[David O'Meara]

if the class is on the model directory then it should have

package model;

at the start of the class file.
The fully qualified class name is now model.A
You refer to the class in Class.forName() using the fully qualified class name ie Class.forName("model.A")

[andrea casini]

Damn it was so simple..

Thank you..

[David O'Meara]

No one said things have to be hard. Reflection is a great tool.
Good job