Initial revision

From-SVN: r104578

libjava/classpath/gnu/java/awt/peer/gtk/GtkClipboardNotifier.java

@@ -0,0 +1,112 @@
+/* GtkClipboardNotifier.java -- Helper for announcing GtkSelection changes.
+   Copyright (C) 2005  Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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.
+
+GNU Classpath 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 GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.peer.gtk;
+
+import java.awt.datatransfer.*;
+
+class GtkClipboardNotifier extends Thread
+{
+  /** Whether or not to announce a GtkSelection change. */
+  private static boolean announceChange;
+
+  /**
+   * The one and only instance. All operations are synchronized on
+   * this.
+   */
+  private static GtkClipboardNotifier notifier = new GtkClipboardNotifier();
+
+  /**
+   * Creates a deamon thread that monitors this for change
+   * announcements.
+   */
+  private GtkClipboardNotifier()
+  {
+    super("GtkClipBoardNotifier");
+    setDaemon(true);
+    start();
+  }
+
+  /**
+   * Notifies that a new GtkSelection has to be announced.
+   */
+  static void announce()
+  {
+    synchronized (notifier)
+      {
+	announceChange = true;
+	notifier.notifyAll();
+      }
+  }
+
+  public void run()
+  {
+    final GtkClipboard clipboard = GtkClipboard.getInstance();
+    while (true)
+      {
+	synchronized (this)
+	  {
+	    while (!announceChange)
+	      {
+		try
+		  {
+		    this.wait();
+		  }
+		catch (InterruptedException ie)
+		  {
+		    // ignore
+		  }
+	      }
+	    announceChange = false;
+	  }
+
+	// Do the actual announcement without the lock held.  We will
+	// notice a new change after this notification has finished.
+	try
+	  {
+	    clipboard.setContents(new GtkSelection(), null);
+	  }
+	catch (Throwable t)
+	  {
+	    // should never happen, but might if we have some faulty
+	    // listener.
+	    t.printStackTrace();
+	  }
+      }
+  }
+}