source: trunk/jabberit_messenger/java_source/src/nu/fw/jeti/plugins/PluginsInfo.java @ 1097

/* 
 *      Jeti, a Java Jabber client, Copyright (C) 2003 E.S. de Boer  
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *      For questions, comments etc, 
 *      use the website at http://jeti.jabberstudio.org
 *  or mail/IM me at jeti@jabber.org
 *
 *      Created on 26-dec-2003
 */
 
package nu.fw.jeti.plugins;

import java.lang.ref.WeakReference;
import java.lang.reflect.Method;
import java.text.MessageFormat;
import java.util.*;
import javax.xml.parsers.SAXParser;
import nu.fw.jeti.backend.Start;
import nu.fw.jeti.jabber.Backend;
import nu.fw.jeti.util.I18N;
import nu.fw.jeti.util.Preferences;

/**
 * @author E.S. de Boer
 *
 */
public class PluginsInfo
{
        private static Backend backend;
        private static Map loadedPlugins = new HashMap();
        public static Map loadedPreferencePanels = new HashMap();
        private static Map pluginInstances = new HashMap();
        private static String pluginsJava;
                        
        public PluginsInfo( Backend backend, Start start )
        {
                PluginsInfo.backend             = backend;
                PluginsInfo.pluginsJava = nu.fw.jeti.applet.Jeti.JAVAPLUGINS;
                
                /**
                 * Carregando plugins:
                 * 
                 * nu.fw.jeti.plugins.<NOME_do_Plugin>.Plugin.init( backend );
                 * loadedPlugins.put("<NOME_do_Plugin>", nu.fw.jeti.plugins.<NOME_do_Plugin>.Plugin.class);
                 * 
                 * Exemplo : Plugin xhtml
                 * nu.fw.jeti.plugins.xhtml.Plugin.init( backend );
                 * loadedPlugins.put("xhtml", nu.fw.jeti.plugins.xhtml.Plugin.class);
                 */
                
                String[] plugins = pluginsJava.split(",");      
                
                for(int i = 0 ; i < plugins.length; i++)
                        PluginsInfo.loadPlugin(plugins[i].toString());
        }

        public static boolean isPluginLoaded(String name)
        {
                return loadedPlugins.containsKey(name);
        }

        private static void loadPlugin(String name)
        {
                Class loadedClass = nu.fw.jeti.applet.Jeti.getPlugin(name);
                
                try
                {
                        //Init plugin
                        Method m = loadedClass.getMethod("init",new Class[]{Backend.class});
                        m.invoke(null,new Object[]{backend});
                }
                catch(Exception e)
                {
                        e.printStackTrace();
                        return;
                }
                
                loadedPlugins.put(name, loadedClass);
        }
        
        public static void unloadPlugin(String name)
        {
                Class loadedClass = (Class)loadedPlugins.remove(name);
        
                if (loadedClass == null)
                        return;

        System.out.println(I18N.gettext("main.pluginsInfo.Plugin_removing") + " : " + name);
                
        loadedPreferencePanels.remove(name);
        
                List list = (List) pluginInstances.remove(name);
                
                try
                {
                        //unload cleaning
                        Method m = loadedClass.getMethod("unload",new Class[]{Backend.class});
                        m.invoke(null,new Object[]{backend});
                }
                catch(NoSuchMethodException e)
                {
                        System.out.println("ERRO : " + name + " " + I18N.gettext("main.pluginsInfo.has_no_remove"));
                }
                catch(Exception e)
                {
                        e.printStackTrace();
                }
                                
                if ( list == null)
                        return;
                
                for (Iterator i = list.iterator(); i.hasNext();)
                {       
                        //unload loaded plugins
                        Plugins plugin = (Plugins)((WeakReference)i.next()).get();
                        
                        if ( plugin != null )
                                plugin.unload();
                }
                
                System.out.println( "Removed plugin : " + name );
        }
        
        /**
         * Gets a single instance of a plugin, the plugin has to have the static getInstance() method
         * @param name name of the plugin
         * @return instance of the plugin
         */
        public static Object getPluginInstance(String name)
        {
                Object o = null;
                try
                {
                        Class loadedClass = (Class) loadedPlugins.get(name);
                        try
                        {
                                Method m = loadedClass.getMethod("getInstance",null);
                                o = m.invoke(null,null);
                        }
                        catch(NoSuchMethodException e)
                        {
                                System.out.println(name + " has no instance method");
                        }
                        catch(Exception e)
                        {
                                e.printStackTrace();
                        }
                }
                catch (Exception ie)
                {
                        ie.printStackTrace();
                        return null;
                }

                return o;
        }
        
        public static Plugins newPluginInstance(String name)
        {
                Object o = null;
                
                try
                {
                        o = ((Class) loadedPlugins.get(name)).newInstance();
                        addInstance(name,o);
                }
                catch (Exception ie)
                {
                        ie.printStackTrace();
                        return null;
                }
                
                return (Plugins) o;
        }

        private static void addInstance(String name, Object object)
        {
                List list = (List) pluginInstances.get(name);
                
                if (list == null)
                {
                        list = new LinkedList();
                        pluginInstances.put(name, list);
                }
                
                list.add(new WeakReference(object));
        }
        
        public static String getAbout()
        {
                StringBuffer buffer = new StringBuffer();
                
                for(Iterator i = loadedPlugins.entrySet().iterator();i.hasNext();)
                {
                        Map.Entry entry = (Map.Entry)i.next();
                        String text = null;
                        try
                        {
                                 text = (String) ((Class)entry.getValue()).getField("ABOUT").get(null);
                        }
                        catch (Exception e1){}
                        
                        if( text != null)
                                buffer.append("\n - " + (String)entry.getKey() + '\n' + text);
                }
                 
                return buffer.toString(); 
        } 
        
        // Remove plugins
        public void exit()
        {
                String[] temp = new String[loadedPlugins.size()];
                loadedPlugins.keySet().toArray(temp);
                
                for(int i=0;i<temp.length;i++)
                {
                        unloadPlugin(temp[i]);
                }
                
                System.out.println(I18N.gettext("main.pluginsInfo.plugins_unloaded"));
        }
}

/*
 * Overrides for emacs
 * Local variables:
 * tab-width: 4
 * End:
 */