/common/util/BrowserLauncher.java

/*
 *  SSHTools - Java SSH2 API
 *
 *  Copyright (C) 2002 Lee David Painter.
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public License
 *  as published by the Free Software Foundation; either version 2 of
 *  the License, or (at your option) any later version.
 *
 *  You may also distribute it and/or modify it under the terms of the
 *  Apache style J2SSH Software License. A copy of which should have
 *  been provided with the distribution.
 *
 *  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
 *  License document supplied with your distribution for more details.
 *
 */

package com.sshtools.common.util;

import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 *
 *
 * @author $author$
 * @version $Revision: 1.14 $
 */
public class BrowserLauncher {
  private static int jvm;
  private static Object browser;
  private static boolean loadedWithoutErrors;
  private static Class mrjFileUtilsClass;
  private static Class mrjOSTypeClass;
  private static Class macOSErrorClass;
  private static Class aeDescClass;
  private static Constructor aeTargetConstructor;
  private static Constructor appleEventConstructor;
  private static Constructor aeDescConstructor;
  private static Method findFolder;
  private static Method getFileType;
  private static Method makeOSType;
  private static Method putParameter;
  private static Method sendNoReply;
  private static Object kSystemFolderType;
  private static Integer keyDirectObject;
  private static Integer kAutoGenerateReturnID;
  private static Integer kAnyTransactionID;
  private static final int MRJ_2_0 = 0;
  private static final int MRJ_2_1 = 1;
  private static final int WINDOWS_NT = 2;
  private static final int WINDOWS_9x = 3;
  private static final int OTHER = -1;
  private static final String FINDER_TYPE = "FNDR";
  private static final String FINDER_CREATOR = "MACS";
  private static final String GURL_EVENT = "GURL";
  private static final String FIRST_WINDOWS_PARAMETER = "/c";
  private static final String SECOND_WINDOWS_PARAMETER = "start";
  private static final String NETSCAPE_OPEN_PARAMETER_START =
      " -remote 'openURL(";
  private static final String NETSCAPE_OPEN_PARAMETER_END = ")'";
  private static String errorMessage;

  static {
    loadedWithoutErrors = true;

    String osName = System.getProperty("os.name");

    if ("Mac OS".equals(osName)) {
      String mrjVersion = System.getProperty("mrj.version");
      String majorMRJVersion = mrjVersion.substring(0, 3);

      try {
        double version = Double.valueOf(majorMRJVersion).doubleValue();

        if (version == 2) {
          jvm = MRJ_2_0;
        }
        else if (version >= 2.1) {
          // For the time being, assume that all post-2.0 versions of MRJ work the same
          jvm = MRJ_2_1;
        }
        else {
          loadedWithoutErrors = false;
          errorMessage = "Unsupported MRJ version: " + version;
        }
      }
      catch (NumberFormatException nfe) {
        loadedWithoutErrors = false;
        errorMessage = "Invalid MRJ version: " + mrjVersion;
      }
    }
    else if (osName.startsWith("Windows")) {
      if (osName.indexOf("9") != -1) {
        jvm = WINDOWS_9x;
      }
      else {
        jvm = WINDOWS_NT;
      }
    }
    else {
      jvm = OTHER;
    }

    if (loadedWithoutErrors) { // if we haven't hit any errors yet
      loadedWithoutErrors = loadClasses();
    }
  }

  private BrowserLauncher() {
  }

  private static boolean loadClasses() {
    switch (jvm) {
      case MRJ_2_0:

        try {
          Class aeTargetClass = Class.forName("com.apple.MacOS.AETarget");
          macOSErrorClass = Class.forName("com.apple.MacOS.MacOSError");

          Class osUtilsClass = Class.forName("com.apple.MacOS.OSUtils");
          Class appleEventClass = Class.forName(
              "com.apple.MacOS.AppleEvent");
          Class aeClass = Class.forName("com.apple.MacOS.ae");
          aeDescClass = Class.forName("com.apple.MacOS.AEDesc");
          aeTargetConstructor = aeTargetClass.getDeclaredConstructor(new Class[] {
              int.class
          });
          appleEventConstructor = appleEventClass.getDeclaredConstructor(new
              Class[] {
              int.class, int.class, aeTargetClass, int.class,
              int.class
          });
          aeDescConstructor = aeDescClass.getDeclaredConstructor(new Class[] {
              String.class
          });
          makeOSType = osUtilsClass.getDeclaredMethod("makeOSType",
              new Class[] {String.class});
          putParameter = appleEventClass.getDeclaredMethod("putParameter",
              new Class[] {int.class, aeDescClass});
          sendNoReply = appleEventClass.getDeclaredMethod("sendNoReply",
              new Class[] {});

          Field keyDirectObjectField = aeClass.getDeclaredField(
              "keyDirectObject");
          keyDirectObject = (Integer) keyDirectObjectField.get(null);

          Field autoGenerateReturnIDField = appleEventClass
              .getDeclaredField("kAutoGenerateReturnID");
          kAutoGenerateReturnID = (Integer) autoGenerateReturnIDField.get(null);

          Field anyTransactionIDField = appleEventClass.getDeclaredField(
              "kAnyTransactionID");
          kAnyTransactionID = (Integer) anyTransactionIDField.get(null);
        }
        catch (ClassNotFoundException cnfe) {
          errorMessage = cnfe.getMessage();

          return false;
        }
        catch (NoSuchMethodException nsme) {
          errorMessage = nsme.getMessage();

          return false;
        }
        catch (NoSuchFieldException nsfe) {
          errorMessage = nsfe.getMessage();

          return false;
        }
        catch (IllegalAccessException iae) {
          errorMessage = iae.getMessage();

          return false;
        }

        break;

      case MRJ_2_1:

        try {
          mrjFileUtilsClass = Class.forName("com.apple.mrj.MRJFileUtils");
          mrjOSTypeClass = Class.forName("com.apple.mrj.MRJOSType");

          Field systemFolderField = mrjFileUtilsClass.getDeclaredField(
              "kSystemFolderType");
          kSystemFolderType = systemFolderField.get(null);
          findFolder = mrjFileUtilsClass.getDeclaredMethod("findFolder",
              new Class[] {mrjOSTypeClass});
          getFileType = mrjFileUtilsClass.getDeclaredMethod("getFileType",
              new Class[] {File.class});
        }
        catch (ClassNotFoundException cnfe) {
          errorMessage = cnfe.getMessage();

          return false;
        }
        catch (NoSuchFieldException nsfe) {
          errorMessage = nsfe.getMessage();

          return false;
        }
        catch (NoSuchMethodException nsme) {
          errorMessage = nsme.getMessage();

          return false;
        }
        catch (SecurityException se) {
          errorMessage = se.getMessage();

          return false;
        }
        catch (IllegalAccessException iae) {
          errorMessage = iae.getMessage();

          return false;
        }

        break;
    }

    return true;
  }

  private static Object locateBrowser() {
    if (browser != null) {
      return browser;
    }

    switch (jvm) {
      case MRJ_2_0:

        try {
          Integer finderCreatorCode = (Integer) makeOSType.invoke(null,
              new Object[] {FINDER_CREATOR});
          Object aeTarget = aeTargetConstructor.newInstance(new Object[] {
              finderCreatorCode
          });
          Integer gurlType = (Integer) makeOSType.invoke(null,
              new Object[] {GURL_EVENT});
          Object appleEvent = appleEventConstructor.newInstance(new Object[] {
              gurlType, gurlType, aeTarget, kAutoGenerateReturnID,
              kAnyTransactionID
          });

          // Don't set browser = appleEvent because then the next time we call
          // locateBrowser(), we'll get the same AppleEvent, to which we'll already have
          // added the relevant parameter. Instead, regenerate the AppleEvent every time.
          // There's probably a way to do this better; if any has any ideas, please let
          // me know.
          return appleEvent;
        }
        catch (IllegalAccessException iae) {
          browser = null;
          errorMessage = iae.getMessage();

          return browser;
        }
        catch (InstantiationException ie) {
          browser = null;
          errorMessage = ie.getMessage();

          return browser;
        }
        catch (InvocationTargetException ite) {
          browser = null;
          errorMessage = ite.getMessage();

          return browser;
        }

        case MRJ_2_1:

          File systemFolder;

          try {
            systemFolder = (File) findFolder.invoke(null,
                new Object[] {kSystemFolderType});
          }
          catch (IllegalArgumentException iare) {
            browser = null;
            errorMessage = iare.getMessage();

            return browser;
          }
          catch (IllegalAccessException iae) {
            browser = null;
            errorMessage = iae.getMessage();

            return browser;
          }
          catch (InvocationTargetException ite) {
            browser = null;
            errorMessage = ite.getTargetException().getClass() + ": "
                + ite.getTargetException().getMessage();

            return browser;
          }

          String[] systemFolderFiles = systemFolder.list();

          // Avoid a FilenameFilter because that can't be stopped mid-list
          for (int i = 0; i < systemFolderFiles.length; i++) {
            try {
              File file = new File(systemFolder, systemFolderFiles[i]);

              if (!file.isFile()) {
                continue;
              }

              Object fileType = getFileType.invoke(null,
                  new Object[] {file});

              if (FINDER_TYPE.equals(fileType.toString())) {
                browser = file.toString(); // Actually the Finder, but that's OK

                return browser;
              }
            }
            catch (IllegalArgumentException iare) {
              browser = browser;
              errorMessage = iare.getMessage();

              return null;
            }
            catch (IllegalAccessException iae) {
              browser = null;
              errorMessage = iae.getMessage();

              return browser;
            }
            catch (InvocationTargetException ite) {
              browser = null;
              errorMessage = ite.getTargetException().getClass() + ": "
                  + ite.getTargetException().getMessage();

              return browser;
            }
          }

          browser = null;

          break;

      case WINDOWS_NT:
        browser = "cmd.exe";

        break;

      case WINDOWS_9x:
        browser = "command.com";

        break;

      case OTHER:
      default:

        //browser = "netscape"; surely mozilla is the thing these days
        browser = "mozilla";

        break;
    }

    return browser;
  }

  /**
   *
   *
   * @param url
   *
   * @throws IOException
   */
  public static void openURL(String url) throws IOException {
    if (!loadedWithoutErrors) {
      throw new IOException("Exception in finding browser: "
                            + errorMessage);
    }

    Object browser = locateBrowser();

    if (browser == null) {
      throw new IOException("Unable to locate browser: " + errorMessage);
    }

    switch (jvm) {
      case MRJ_2_0:

        Object aeDesc = null;

        try {
          aeDesc = aeDescConstructor.newInstance(new Object[] {url});
          putParameter.invoke(browser,
                              new Object[] {keyDirectObject, aeDesc});
          sendNoReply.invoke(browser, new Object[] {});
        }
        catch (InvocationTargetException ite) {
          throw new IOException(
              "InvocationTargetException while creating AEDesc: "
              + ite.getMessage());
        }
        catch (IllegalAccessException iae) {
          throw new IOException(
              "IllegalAccessException while building AppleEvent: "
              + iae.getMessage());
        }
        catch (InstantiationException ie) {
          throw new IOException(
              "InstantiationException while creating AEDesc: "
              + ie.getMessage());
        }
        finally {
          aeDesc = null; // Encourage it to get disposed if it was created
          browser = null; // Ditto
        }

        break;

      case MRJ_2_1:
        Runtime.getRuntime().exec(new String[] { (String) browser, url});

        break;

      case WINDOWS_NT:
      case WINDOWS_9x:
        Runtime.getRuntime().exec(new String[] {
                                  (String) browser, FIRST_WINDOWS_PARAMETER,
                                  SECOND_WINDOWS_PARAMETER, url
        });

        break;

      case OTHER:

        // Assume that we're on Unix and that Netscape is installed
        // First, attempt to open the URL in a currently running session of Netscape
        Process process = Runtime.getRuntime().exec( (String) browser
            + NETSCAPE_OPEN_PARAMETER_START + url
            + NETSCAPE_OPEN_PARAMETER_END);

        try {
          int exitCode = process.waitFor();

          if (exitCode != 0) { // if Netscape was not open
            Runtime.getRuntime().exec(new String[] { (String) browser, url});
          }
        }
        catch (InterruptedException ie) {
          throw new IOException(
              "InterruptedException while launching browser: "
              + ie.getMessage());
        }

        break;

      default:

        // This should never occur, but if it does, we'll try the simplest thing possible
        Runtime.getRuntime().exec(new String[] { (String) browser, url});

        break;
    }
  }
}