=head1 NAME

Inline::Java::PerlNatives - Map Java native methods to Perl functions.


=for comment

   use Inline Java => <<'END' ;
      import org.perl.inline.java.* ;

      class Pod_PN extends InlineJavaPerlNatives {
         public Pod_PN() throws InlineJavaException {

         native public String hello() ;

   package Pod_PN ;
   sub hello {
      return "hi!" ;

   package main ;
   my $b = new Pod_PN() ;
   print($b->hello() . "\n") ; # prints hi!

=for comment


WARNING: C<Inline::Java::PerlNatives> is still experimental.

C<Inline::Java::PerlNatives> allows you to define your callbacks as native 
Java methods that are automatically linked to Perl subroutines. You implement 
the Perl subroutine directly in the package in which C<Inline::Java> binds 
your class. You can do this by making your Java code extend the
C<org.perl.inline.java.InlineJavaPerlNatives> class.

Note: PerlNatives requires J2SDK version >= 1.4

=head1 USING THE org.perl.inline.java.InlineJavaPerlNatives CLASS

Let's revisit an example from the L<Inline::Java::Callback> documentation:

=for comment

   use Inline Java => <<'END' ;
      import java.util.* ;
      import org.perl.inline.java.* ;
      import javax.swing.* ;
      import java.awt.event.* ;

      class Pod_Button_PN extends InlineJavaPerlNatives
                          implements ActionListener {
         public Pod_Button_PN() throws InlineJavaException {
            JFrame frame = new JFrame("Pod_Button") ;
            frame.setSize(100,100) ;
            JButton button = new JButton("Click Me!") ;
            frame.getContentPane().add(button) ;
            button.addActionListener(this) ;
            frame.show() ;

         public void actionPerformed(ActionEvent e){
            button_pressed() ;

         native public void button_pressed() ;

   package Pod_Button_PN ;
   sub button_pressed {
      print('click!' . "\n") ; # prints click!
      $main::b->StopCallbackLoop() ;

   package main ;
   $main::b = new Pod_Button_PN() ;
   $main::b->StartCallbackLoop() ;

=for comment

Extending InlineJavaPerlNatives tells C<Inline::Java> that all native methods 
declared in that class should be linked to Perl subroutines implemented in the 
approriate package. You can then call these methods from Java just like regular 
methods. You can even call them from Perl if they are public. 


C<Inline::Java::PerlNatives> has a few limits that one must be aware of:

=over 4

=item 1

You cannot declare 2 native methods with the same name in a class (even if they 
have different signatures).

=item 2

Native methods can have arguments of any type, but they must return either void 
or an Object (use wrappers like Integer and Double to return primitive types).

=item 3

Even if you do not declare them, InlineJavaException and InlineJavaPerlException 
exceptions (as well as others) may be thrown from within the native methods


=head1 SEE ALSO

L<Inline::Java>, L<Inline::Java::Callback>, L<Inline::Java::PerlInterpreter>.

=head1 AUTHOR

Patrick LeBoutillier <patl@cpan.org> is the author of Inline::Java.


Copyright (c) 2001-2004, Patrick LeBoutillier.

All Rights Reserved. This module is free software. It may be used,
redistributed and/or modified under the terms of the Perl Artistic
License. See http://www.perl.com/perl/misc/Artistic.html for more