applet.java

java 平台 telnet 繁体中文版

/*
 * This file is part of "The Java Telnet Application".
 *
 * This 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, or (at your option)
 * any later version.
 *
 * "The Java Telnet Application" 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 software; see the file COPYING.  If not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */
package de.mud.jta;

import de.mud.jta.event.OnlineStatusListener;
import de.mud.jta.event.SocketRequest;
import de.mud.jta.event.ReturnFocusRequest;
import de.mud.jta.event.FocusStatusListener;
import de.mud.jta.event.AppletRequest;
import de.mud.jta.event.SoundListener;

import java.util.Properties;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Vector;

import java.io.IOException;
import java.net.URL;

import java.awt.Frame;
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.Panel;
import java.awt.Label;
import java.awt.Button;
import java.awt.Color;
import java.awt.Component;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.MenuShortcut;
import java.awt.PrintJob;

import java.awt.datatransfer.Clipboard;

import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;

import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;

/**
 * <B>The Java Telnet Applet</B><P>
 * This is the implementation of whole set of applications. It's modular
 * structure allows to configure the software to act either as a sophisticated
 * terminal emulation and/or, adding the network backend, as telnet 
 * implementation. Additional modules provide features like scripting or an
 * improved graphical user interface.<P>
 * This software is written entirely in Java<SUP>tm</SUP>.<P>
 * This is the <I>Applet</I> implementation for the software. It initializes
 * the system and adds all needed components, such as the telnet backend and
 * the terminal front end. 
 * <P>
 * <B>Maintainer:</B> Matthias L. Jugel
 *
 * @version $Id: Applet.java,v 2.32 2001/03/06 12:05:22 leo Exp $
 * @author Matthias L. Jugel, Marcus Mei遪er
 */
public class Applet extends java.applet.Applet {

  private final static int debug = 0;

  private String frameTitle = null;
  private java.awt.Container appletFrame;

  /** holds the defaults */
  private Properties options = new Properties();

  /** hold the common part of the jta */
  private Common pluginLoader;

  /** hold the host and port for our connection */
  private String host, port;

  /** disconnect on leave, this is to force applets to break the connection */
  private boolean disconnect = true;
  /** connect on startup, this is to force applets to connect on detach */
  private boolean connect = false;
  /** close the window (if it exists) after the connection is lost */
  private boolean disconnectCloseWindow = true;

  private Plugin focussedPlugin;
  private Clipboard clipboard;
  private boolean online = false;

  /**
   * Read all parameters from the applet configuration and
   * do initializations for the plugins and the applet.
   */
  public void init() {
    if(debug > 0) System.err.println("Applet: init()");
    if(pluginLoader == null) {
      try {
        options.load(Applet.class
	  .getResourceAsStream("/de/mud/jta/default.conf"));
      } catch(Exception e) {
	try {
          URL url = new URL(getCodeBase() + "default.conf");
          options.load(url.openStream());
	} catch(Exception e1) {
	  System.err.println("jta: cannot load default.conf");
	  System.err.println("jta: try extracting it from the jar file");
	  System.err.println("jta: expected file here: "
	                    +getCodeBase()+ "default.conf");
        }
      }

      String value;

      // try to load the local configuration and merge it with the defaults
      if((value = getParameter("config")) != null) {
        Properties appletParams = new Properties();
	URL url = null;
	try {
	  url = new URL(value);
	} catch(Exception e) {
	  try {
	    url = new URL(getCodeBase() + value);
	  } catch(Exception ce) {
	    System.err.println("jta: could not find config file: "+ce);
	  }
	}

	if(url != null) {
	  try {
	    appletParams.load(Applet.class.getResourceAsStream("/de/mud/jta/" + value));
	    Enumeration ape = appletParams.keys();
	    while(ape.hasMoreElements()) {
	      String key = (String)ape.nextElement();
	      options.put(key, appletParams.getProperty(key));
	    }
	  } catch ( Exception e )
	  {
	    try
	    {
	      appletParams.load(url.openStream());
	      Enumeration ape = appletParams.keys();
	      while(ape.hasMoreElements()) {
	        String key = (String)ape.nextElement();
	        options.put(key, appletParams.getProperty(key));
	      }
	    } catch ( Exception e2 )
	    {
	      System.err.println("jta: could not load config file: "+e2);
	    }
	  }
	}
      }

      // see if there are parameters in the html to override properties
      parameterOverride(options);

      // configure the application and load all plugins
      pluginLoader = new Common(options);

      // set the host to our code base, no other hosts are allowed anyway
      host = options.getProperty("Socket.host");
      if(host == null)
        host = getCodeBase().getHost();
      port = options.getProperty("Socket.port");
      if(port == null)
        port = "23";

    if((new Boolean(options.getProperty("Applet.connect"))
       .booleanValue()))
      connect = true;
    if(!(new Boolean(options.getProperty("Applet.disconnect"))
       .booleanValue()))
      disconnect = false;

    if(!(new Boolean(options.getProperty("Applet.disconnect.closeWindow"))
            .booleanValue()))
       disconnectCloseWindow = false;

    frameTitle = options.getProperty("Applet.detach.title");

    if((new Boolean(options.getProperty("Applet.detach"))).booleanValue()) {
       if(frameTitle == null)
         appletFrame = new Frame("jta: "+host+(port.equals("23")?"":" "+port));
       else
         appletFrame = new Frame(frameTitle);
     } else
       appletFrame = this;

      appletFrame.setLayout(new BorderLayout());

      Hashtable componentList = pluginLoader.getComponents();
      Enumeration names = componentList.keys();
      while(names.hasMoreElements()) {
        String name = (String)names.nextElement();
        Component c = (Component)componentList.get(name);
        if((value = options.getProperty("layout."+name)) != null) {
          appletFrame.add(value, c);
        } else {
          System.err.println("jta: no layout property set for '"+name+"'");
          System.err.println("jta: ignoring '"+name+"'");
	}
      }

      pluginLoader.registerPluginListener(new SoundListener() {
        public void playSound(URL audioClip) {
	  Applet.this.getAudioClip(audioClip).play();
	}
      });

      pluginLoader.broadcast(new AppletRequest(this));
      if(appletFrame != this) {
	final String startText = options.getProperty("Applet.detach.startText");
	final String stopText = options.getProperty("Applet.detach.stopText");
	final Button close =  new Button();

	// this works for Netscape only!
        Vector privileges = 
	  Common.split(options.getProperty("Applet.Netscape.privilege"), ',');
	Class privilegeManager = null;
	Method enable = null;
        try {
	  privilegeManager = 
	    Class.forName("netscape.security.PrivilegeManager");
	  enable = privilegeManager
	    .getMethod("enablePrivilege", new Class[] { String.class });
	} catch(Exception e) {
	  System.err.println("Applet: This is not Netscape ...");
        }

	if(privilegeManager != null && enable != null)
	  for(int i = 0; i < privileges.size(); i++) try {
	    enable.invoke(privilegeManager, 
	                  new Object[] { privileges.elementAt(i) });