1 /* Desktop.java -- enable desktop integration between java programs and system
2  programs.
3  Copyright (C) 2006 Free Software Foundation, Inc.
4 
5  This file is part of GNU Classpath.
6 
7  GNU Classpath is free software; you can redistribute it and/or modify
8  it under the terms of the GNU General Public License as published by
9  the Free Software Foundation; either version 2, or (at your option)
10  any later version.
11 
12  GNU Classpath is distributed in the hope that it will be useful, but
13  WITHOUT ANY WARRANTY; without even the implied warranty of
14  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  General Public License for more details.
16 
17  You should have received a copy of the GNU General Public License
18  along with GNU Classpath; see the file COPYING.  If not, write to the
19  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20  02110-1301 USA.
21 
22  Linking this library statically or dynamically with other modules is
23  making a combined work based on this library.  Thus, the terms and
24  conditions of the GNU General Public License cover the whole
25  combination.
26 
27  As a special exception, the copyright holders of this library give you
28  permission to link this library with independent modules to produce an
29  executable, regardless of the license terms of these independent
30  modules, and to copy and distribute the resulting executable under
31  terms of your choice, provided that you also meet, for each linked
32  independent module, the terms and conditions of the license of that
33  module.  An independent module is a module which is not derived from
34  or based on this library.  If you modify this library, you may extend
35  this exception to your version of the library, but you are not
36  obligated to do so.  If you do not wish to do so, delete this
37  exception statement from your version. */
38 
39 
40 package java.awt;
41 
42 import java.awt.peer.DesktopPeer;
43 import java.io.File;
44 import java.io.IOException;
45 import java.net.URI;
46 
47 /**
48  * This class enables Java application to access system commands to perform
49  * desktop oriented operations, like writing and sending emails, or surfing
50  * webpages with the system browser or editing/printing files with a default
51  * editor. Methods are provided to handle these common operations, plus an
52  * <code>open</code> command selects a default registered application for the
53  * specified file type. For example, opening an odf file results in launching
54  * OpenOffice. If an operation is not supported, or the application fails to
55  * launch, an exception is generated.
56  *
57  * <strong>Implementation note: </strong>As this class is used to manage Desktop
58  * integration, we provide some extension to configure the behaviour of this
59  * class depending on the type of dektop that is detected.<br />
60  *
61  * First of all, we support 5 system properties that can be used to define
62  * the application to launch in any given case. These properties are:<br />
63  * <br />
64  * <code>gnu.java.awt.peer.Desktop.html.command</code><br />
65  * <code>gnu.java.awt.peer.Desktop.mail.command</code><br />
66  * <code>gnu.java.awt.peer.Desktop.edit.command</code><br />
67  * <code>gnu.java.awt.peer.Desktop.print.command</code><br />
68  * <code>gnu.java.awt.peer.Desktop.open.command</code><br />
69  * <br />
70  * <br />
71  * These can be specified from the command line and have priority on every
72  * other setting.<br />
73  * <br />
74  * The second method supported is defining a Java preference.<br />
75  * The main preference node is a <strong>user node</strong> relative to the
76  * class <code>gnu.java.awt.peer.ClasspathDesktopPeer</code>. This node
77  * contains a child for each supported operation. The key for each type is
78  * always <code>command</code>:
79  * <br /><br />
80  * <code>gnu.java.awt.peer.Desktop.html.command</code><br />
81  * <code>gnu.java.awt.peer.Desktop.mail.command</code><br />
82  * <code>gnu.java.awt.peer.Desktop.edit.command</code><br />
83  * <code>gnu.java.awt.peer.Desktop.print.command</code><br />
84  * <code>gnu.java.awt.peer.Desktop.open.command</code><br />
85  * <br />
86  * <br />
87  * The access to these keys is done with the Preference API or, if outside
88  * of the java scope, is done in a backend dependent way. For example,
89  * with the GConf backend, you can access these properties
90  * with (may not be accurate on your system):
91  * <br /><br />
92  * <code>
93  * gconftool-2 -g /apps/classpath/gnu/java/awt/peer/Desktop/html/command
94  * </code>
95  *
96  * @author Mario Torre <neugens@limasoftware.net>
97  * @since 1.6
98  */
99 public class Desktop
100 {
101   /**
102    * Represents an action type supported by a platform.
103    *
104    * To determine if a given action is supported by the platform,
105    * use the <code>Desktop.isSupported(java.awt.Desktop.Action)</code>
106    * method.
107    *
108    * @author Mario Torre <neugens@limasoftware.net>
109    */
110   public enum Action
111   {
112     BROWSE, EDIT, MAIL, OPEN, PRINT
113   }
114 
115   private DesktopPeer peer;
116 
Desktop()117   private Desktop()
118   {
119     /* nothing to be done */
120   }
121 
122   /**
123    * Returns an instance of the Desktop Class.
124    *
125    * If this implementation does not support Desktop, an
126    * UnsupportedOperationException will be thrown.
127    * Also, an HeadlessException will be generated if
128    * GraphicsEnvironment.isHeadless() returns true.
129    *
130    * @throws UnsupportedOperationException
131    * @throws HeadlessException
132    */
getDesktop()133   public static Desktop getDesktop() throws UnsupportedOperationException,
134       HeadlessException
135   {
136     if (GraphicsEnvironment.isHeadless())
137       throw new HeadlessException();
138 
139     if (!Desktop.isDesktopSupported())
140       throw new UnsupportedOperationException();
141 
142     Desktop desktop = new Desktop();
143     desktop.peer = Toolkit.getDefaultToolkit().createDesktopPeer(desktop);
144 
145     return desktop;
146   }
147 
148   /**
149    * Check if this implementation supports Desktop.
150    * If true, use getDesktop to get an instance of this class.
151    *
152    * This implementation will return false when GraphicsEnvironment.isHeadless
153    * returns true.
154    *
155    * @return true if this class is supported on the current platform;
156    * false otherwise
157    */
isDesktopSupported()158   public static boolean isDesktopSupported()
159   {
160     if (GraphicsEnvironment.isHeadless())
161       return false;
162 
163     return true;
164   }
165 
166   /**
167    * Check if the given Action is supported by this implementation.
168    *
169    * @param action
170    * @return
171    */
isSupported(Desktop.Action action)172   public boolean isSupported(Desktop.Action action)
173   {
174     return peer.isSupported(action);
175   }
176 
177   /**
178    * Launches the Desktop default browser to open the given <code>uri</code>.
179    *
180    * If a security manager exists and denies
181    * AWTPermission("showWindowWithoutWarningBanner"),a SecurityException will
182    * be generated.
183    *
184    * @param uri
185    * @throws IOException
186    */
browse(URI uri)187   public void browse(URI uri)
188     throws IOException
189   {
190     peer.browse(uri);
191   }
192 
193   /**
194    * Launch the edit command to edit this file.
195    * File should already exist before the editing starts.
196    *
197    * If a security manager exists and
198    * SecurityManager.checkRead(java.lang.String) method denies read access to
199    * the file, or SecurityManager.checkPrintJobAccess() method denies the
200    * permission to print the file, a SecurityException will be generated.
201    *
202    * @param file
203    * @throws IOException
204    */
edit(File file)205   public void edit(File file)
206     throws IOException
207   {
208     peer.edit(file);
209   }
210 
211   /**
212    * Launches the Desktop default mailer.
213    *
214    * If a security manager exists and denies
215    * AWTPermission("showWindowWithoutWarningBanner"), a SecurityException will
216    * be generated.
217    *
218    * @throws IOException
219    */
mail()220   public void mail()
221     throws IOException
222   {
223     peer.mail();
224   }
225 
226   /**
227    * Launches the Desktop default mailer, with the given mailtoURI
228    * as agrument. The <code>mailtoURI</code> must conform to the
229    * {@link http://www.ietf.org/rfc/rfc2368.txt The mailto URL scheme (RFC 2368)}
230    *
231    * If a security manager exists and denies
232    * AWTPermission("showWindowWithoutWarningBanner"), a SecurityException will
233    * be generated.
234    *
235    * @param mailtoURI
236    * @throws IOException
237    */
mail(URI mailtoURI)238   public void mail(URI mailtoURI)
239     throws IOException
240   {
241     peer.mail(mailtoURI);
242   }
243 
244   /**
245    * Launches the Desktop default application to open the given File.
246    * If <code>file</code> is a directory, a file manager is launched.
247    *
248    * @param file
249    * @throws IOException
250    */
open(File file)251   public void open(File file)
252     throws IOException
253   {
254     peer.open(file);
255   }
256 
257   /**
258    * Launch the print program to print this file.
259    *
260    * @param file
261    * @throws IOException
262    */
print(File file)263   public void print(File file)
264     throws IOException
265   {
266     peer.print(file);
267   }
268 }
269