Add Context refresh thread in DesktopContext

modules/DesktopContext/src/main/java/org/gephi/desktop/context/ContextRefreshThread.java

+/*
+ Copyright 2008-2010 Gephi
+ Authors : Mathieu Bastian <mathieu.bastian@gephi.org>
+ Website : http://www.gephi.org
+
+ This file is part of Gephi.
+
+ DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+
+ Copyright 2011 Gephi Consortium. All rights reserved.
+
+ The contents of this file are subject to the terms of either the GNU
+ General Public License Version 3 only ("GPL") or the Common
+ Development and Distribution License("CDDL") (collectively, the
+ "License"). You may not use this file except in compliance with the
+ License. You can obtain a copy of the License at
+ http://gephi.org/about/legal/license-notice/
+ or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the
+ specific language governing permissions and limitations under the
+ License.  When distributing the software, include this License Header
+ Notice in each file and include the License files at
+ /cddl-1.0.txt and /gpl-3.0.txt. If applicable, add the following below the
+ License Header, with the fields enclosed by brackets [] replaced by
+ your own identifying information:
+ "Portions Copyrighted [year] [name of copyright owner]"
+
+ If you wish your version of this file to be governed by only the CDDL
+ or only the GPL Version 3, indicate your decision by adding
+ "[Contributor] elects to include this software in this distribution
+ under the [CDDL or GPL Version 3] license." If you do not indicate a
+ single choice of license, a recipient has the option to distribute
+ your version of this file under either the CDDL, the GPL Version 3 or
+ to extend the choice of license to its licensees as provided above.
+ However, if you add GPL Version 3 code and therefore, elected the GPL
+ Version 3 license, then the option applies only if the new code is
+ made subject to such option by the copyright holder.
+
+ Contributor(s):
+
+ Portions Copyrighted 2011 Gephi Consortium.
+ */
+package org.gephi.desktop.context;
+
+import java.util.Timer;
+import java.util.TimerTask;
+import org.gephi.graph.api.GraphModel;
+import org.gephi.graph.api.GraphObserver;
+
+/**
+ *
+ * @author mbastian
+ */
+public class ContextRefreshThread extends TimerTask {
+
+    private static final long PERIOD = 500;
+    private final Timer timer;
+    private final GraphModel graphModel;
+    private final Runnable listener;
+    private GraphObserver observer;
+
+    public ContextRefreshThread(GraphModel graphModel, Runnable listener) {
+        this.timer = new Timer("Context Refresh Thread", true);
+        this.graphModel = graphModel;
+        this.listener = listener;
+
+        //Schedule
+        timer.schedule(this, 0, PERIOD);
+    }
+
+    private void initObserver() {
+        if (observer == null || observer.isDestroyed()) {
+            observer = graphModel.getGraphObserver(graphModel.getGraph(graphModel.getVisibleView()), false);
+        }
+    }
+
+    @Override
+    public void run() {
+        initObserver();
+        if (observer.hasGraphChanged()) {
+            listener.run();
+        }
+    }
+
+    public void shutdown() {
+        timer.cancel();
+    }
+
+    public GraphModel getGraphModel() {
+        return graphModel;
+    }
+}