package Log::Log4perl::JavaMap;

use Carp;
use strict;

use constant _INTERNAL_DEBUG => 0;

our %translate = (
    'org.apache.log4j.ConsoleAppender' => 
        'Log::Log4perl::JavaMap::ConsoleAppender',
    'org.apache.log4j.FileAppender'    => 
        'Log::Log4perl::JavaMap::FileAppender',
    'org.apache.log4j.RollingFileAppender'    => 
        'Log::Log4perl::JavaMap::RollingFileAppender',
    'org.apache.log4j.TestBuffer'    => 
        'Log::Log4perl::JavaMap::TestBuffer',
     'org.apache.log4j.jdbc.JDBCAppender'    => 
        'Log::Log4perl::JavaMap::JDBCAppender',
     'org.apache.log4j.SyslogAppender'    => 
        'Log::Log4perl::JavaMap::SyslogAppender',
     'org.apache.log4j.NTEventLogAppender'    => 
        'Log::Log4perl::JavaMap::NTEventLogAppender',
);

our %user_defined;

sub get {
    my ($appender_name, $appender_data) = @_;

    print "Trying to map $appender_name\n" if _INTERNAL_DEBUG;

    $appender_data->{value} ||
            die "ERROR: you didn't tell me how to implement your appender " .
                "'$appender_name'";

    my $perl_class = $translate{$appender_data->{value}} || 
                     $user_defined{$appender_data->{value}} ||
            die "ERROR:  I don't know how to make a '$appender_data->{value}' " .
                "to implement your appender '$appender_name', that's not a " .
                "supported class\n";
    eval {
        eval "require $perl_class";  #see 'perldoc -f require' for why two evals
        die $@ if $@;
    };
    $@ and die "ERROR: trying to set appender for $appender_name to " .
               "$appender_data->{value} using $perl_class failed\n$@  \n";

    my $app = $perl_class->new($appender_name, $appender_data);
    return $app;
}

#an external api to the two hashes
sub translate {
    my $java_class = shift;

    return $translate{$java_class} || 
            $user_defined{$java_class};
}

1;


=head1 NAME

Log::Log4perl::JavaMap - maps java log4j appenders to Log::Dispatch classes

=head1 SYNOPSIS

     ###############################
     log4j.appender.FileAppndr1        = org.apache.log4j.FileAppender
     log4j.appender.FileAppndr1.File   = /var/log/onetime.log
     log4j.appender.FileAppndr1.Append = false

     log4j.appender.FileAppndr1.layout = org.apache.log4j.PatternLayout
     log4j.appender.FileAppndr1.layout.ConversionPattern=%d %4r [%t] %-5p %c %x - %m%n
     ###############################


=head1 DESCRIPTION

If somebody wants to create an appender called C<org.apache.log4j.ConsoleAppender>,
we want to translate it to Log::Dispatch::Screen, and then translate
the log4j options into Log::Dispatch parameters..

=head2 What's Implemented

(Note that you can always use the Log::Dispatch::* module.  By 'implemented'
I mean having a translation class that translates log4j options into
the Log::Dispatch options so you can use log4j rather than log4perl 
syntax in your config file.)

Here's the list of appenders I see on the current (6/2002) log4j site.

These are implemented

    ConsoleAppender     - Log::Dispatch::Screen
    FileAppender        - Log::Dispatch::File
    RollingFileAppender - Log::Dispatch::FileRotate (by Mark Pfeiffer)
    JDBCAppender        - Log::Log4perl::Appender::DBI
    SyslogAppender      - Log::Dispatch::Syslog
    NTEventLogAppender  - Log::Dispatch::Win32EventLog


These should/will/might be implemented
    
    DailyRollingFileAppender - 
    SMTPAppender     - Log::Dispatch::Email::MailSender
    

These might be implemented but they don't have corresponding classes
in Log::Dispatch (yet):

    NullAppender
    TelnetAppender

These might be simulated

    LF5Appender - use Tk?
    ExternallyRolledFileAppender - catch a HUP instead?

These will probably not be implemented

    AsyncAppender
    JMSAppender
    SocketAppender - (ships a serialized LoggingEvent to the server side)
    SocketHubAppender

=head1 ROLL YOUR OWN

Let's say you've in a mixed Java/Perl enviroment and you've
come up with some custom Java appender with behavior you want to 
use in both worlds, C<myorg.customAppender>.  You write a
Perl appender with the same behavior C<Myorg::CustomAppender>. You
want to use one config file accross both applications, so the
config file will have to say 'myorg.customAppender'.  But
the mapping from C<myorg.customAppender> to C<Myorg::CustomAppender>
isn't in this JavaMap class, so what do you do?

In  your Perl code, before you call Log::Log4perl::init(), do this:

    $Log::Log4perl::JavaMap::user_defined{'myorg.customAppender'} = 
        'Myorg::CustomAppender';

and you can use 'myorg.customAppender' in your config file with
impunity.

=head1 SEE ALSO

http://jakarta.apache.org/log4j/docs/

=head1 LICENSE

Copyright 2002-2012 by Mike Schilli E<lt>m@perlmeister.comE<gt> 
and Kevin Goess E<lt>cpan@goess.orgE<gt>.

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself. 

=head1 AUTHOR

Please contribute patches to the project on Github:

    http://github.com/mschilli/log4perl

Send bug reports or requests for enhancements to the authors via our

MAILING LIST (questions, bug reports, suggestions/patches): 
log4perl-devel@lists.sourceforge.net

Authors (please contact them via the list above, not directly):
Mike Schilli <m@perlmeister.com>,
Kevin Goess <cpan@goess.org>

Contributors (in alphabetical order):
Ateeq Altaf, Cory Bennett, Jens Berthold, Jeremy Bopp, Hutton
Davidson, Chris R. Donnelly, Matisse Enzer, Hugh Esco, Anthony
Foiani, James FitzGibbon, Carl Franks, Dennis Gregorovic, Andy
Grundman, Paul Harrington, David Hull, Robert Jacobson, Jason Kohles, 
Jeff Macdonald, Markus Peter, Brett Rann, Peter Rabbitson, Erik
Selberg, Aaron Straup Cope, Lars Thegler, David Viner, Mac Yang.