001    /*--------------------------------------------------------------------------+
002    $Id: VersionUtils.java 26283 2010-02-18 11:18:57Z juergens $
003    |                                                                          |
004    | Copyright 2005-2010 Technische Universitaet Muenchen                     |
005    |                                                                          |
006    | Licensed under the Apache License, Version 2.0 (the "License");          |
007    | you may not use this file except in compliance with the License.         |
008    | You may obtain a copy of the License at                                  |
009    |                                                                          |
010    |    http://www.apache.org/licenses/LICENSE-2.0                            |
011    |                                                                          |
012    | Unless required by applicable law or agreed to in writing, software      |
013    | distributed under the License is distributed on an "AS IS" BASIS,        |
014    | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
015    | See the License for the specific language governing permissions and      |
016    | limitations under the License.                                           |
017    +--------------------------------------------------------------------------*/
018    package edu.tum.cs.commons.version;
019    
020    import java.io.IOException;
021    import java.io.InputStream;
022    import java.net.URL;
023    
024    import javax.swing.JOptionPane;
025    
026    import edu.tum.cs.commons.error.FormatException;
027    import edu.tum.cs.commons.filesystem.FileSystemUtils;
028    
029    /**
030     * Utility code for dealing with versions.
031     * 
032     * @author hummelb
033     * @author $Author: juergens $
034     * @version $Rev: 26283 $
035     * @levd.rating GREEN Hash: 38C0D10E9CCCD8B82949F4612A48AB1B
036     */
037    public class VersionUtils {
038    
039            /**
040             * Checks whether a new version of an application is available. This
041             * retrieves the most recent version from an URL using
042             * {@link #getMostRecentVersion(String)}. If the version could be retrieved
043             * and is more recent than the running version, an informative message box
044             * appears (Swing).
045             */
046            public static void checkForNewVersion(final String appName,
047                            String versionFileUrl, Version runningVersion) {
048                    final Version currentVersion;
049                    try {
050                            currentVersion = getMostRecentVersion(versionFileUrl);
051                    } catch (Exception e) {
052                            // just ignore
053                            return;
054                    }
055    
056                    if (currentVersion.compareTo(runningVersion) > 0) {
057                            javax.swing.SwingUtilities.invokeLater(new Runnable() {
058                                    public void run() {
059                                            JOptionPane
060                                                            .showMessageDialog(null, "The newer version "
061                                                                            + currentVersion + " of " + appName
062                                                                            + " is available for download!",
063                                                                            "Update available",
064                                                                            JOptionPane.INFORMATION_MESSAGE);
065                                    }
066                            });
067                    }
068            }
069    
070            /** Get the most recent version from a file available via an URL. */
071            public static Version getMostRecentVersion(String versionFileUrl)
072                            throws IOException, FormatException {
073                    URL versionURL = new URL(versionFileUrl);
074                    InputStream in = versionURL.openStream();
075                    String versionString = FileSystemUtils.readStream(in);
076                    in.close();
077                    return Version.parseVersion(versionString);
078            }
079    }