applet.java

The Javatm Telnet Application/Applet 很好用的

/*
 * This file is part of "The Java Telnet Application".
 *
 * (c) Matthias L. Jugel, Marcus Meissner 1996-2002. All Rights Reserved.
 *
 * Please visit http://javatelnet.org/ for updates and contact.
 *
 * --LICENSE NOTICE--
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 * --LICENSE NOTICE--
 *
 */
package de.mud.jta;

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

import javax.swing.JApplet;
import javax.swing.JFrame;
import javax.swing.RootPaneContainer;
import java.awt.BorderLayout;
import java.awt.Button;
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.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URL;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;
import java.util.Vector;

/**
 * <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 2.42 2003/12/09 22:04:30 marcus Exp $
 * @author Matthias L. Jugel, Marcus Meissner
 */
public class Applet extends JApplet {

  private final static int debug = 0;

  private String frameTitle = null;
  private RootPaneContainer 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 = (RootPaneContainer)new JFrame("jta: " + host + (port.equals("23")?"":" " + port));
        } else {
          appletFrame = (RootPaneContainer)new JFrame(frameTitle);
        }
      } else {
        appletFrame = (RootPaneContainer)this;
      }
      appletFrame.getContentPane().setLayout(new BorderLayout());

      Map componentList = pluginLoader.getComponents();
      Iterator names = componentList.keySet().iterator();
      while (names.hasNext()) {
        String name = (String) names.next();
        Component c = (Component) componentList.get(name);
        if ((value = options.getProperty("layout." + name)) != null) {
          appletFrame.getContentPane().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 && privileges != null)
          for (int i = 0; i < privileges.size(); i++)
            try {
              enable.invoke(privilegeManager,
                            new Object[]{privileges.elementAt(i)});
              System.out.println("Applet: access for '" +
                                 privileges.elementAt(i) + "' allowed");

            } catch (Exception e) {
              System.err.println("Applet: access for '" +
                                 privileges.elementAt(i) + "' denied");
            }

        // set up the clipboard