Re: Generics ?

From:

Peter Duniho <NpOeStPeAdM@NnOwSlPiAnMk.com>

Newsgroups:

comp.lang.java.programmer

Date:

Thu, 15 Dec 2011 22:03:42 -0800

Message-ID:

<RfWdnc8NJNSiQnfTnZ2dnUVZ_uCdnZ2d@posted.palinacquisition>

On 12/15/11 9:48 PM, Knute Johnson wrote:

Using Java 7, given the class file:

import javax.swing.*;

public class KList extends JList {
[...]
Klist.java:7: warning: [unchecked] unchecked call to
setModel(ListModel<E>) as a
member of the raw type JList
setModel(model);
^
where E is a type-variable:
E extends Object declared in class JList
1 warning

How do you extend this class with generic types?

I haven't been keeping up with the v7 stuff. I take it that in that
version, JList is now generic?

If so, then you need to decide whether KList will also be generic, or
simply inherit some concrete version of JList.

Generic:

   public class KList<E> extends JList<E>
   {
     ListModel<E> model = new DefaultListModel<E>();

     public KList()
     {
       setModel(model);
     }
   }

Concrete:

   // "int" is just for example???could be anything
   public class KList extends JList<int>
   {
     ListModel<int> model = new DefaultListModel<int>();

     public KList()
     {
       setModel(model);
     }
   }

Either of those ought to work.

Pete