SWT: Custom AWT event queue to trap X errors and avoid application crash

git-svn-id: http://svn.code.sf.net/p/davmail/code/trunk@1509 3d1905a2-6b24-0410-a738-b14d5a86fcbd

src/java/davmail/ui/tray/SwtAwtEventQueue.java

@@ -0,0 +1,116 @@
+/*
+ * DavMail POP/IMAP/SMTP/CalDav/LDAP Exchange Gateway
+ * Copyright (C) 2010  Mickael Guessant
+ *
+ * This program 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
+ * of the License, or (at your option) any later version.
+ *
+ * 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
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package davmail.ui.tray;
+
+import org.apache.log4j.Logger;
+import org.eclipse.swt.internal.gtk.OS;
+
+import java.awt.*;
+import java.util.EmptyStackException;
+
+/**
+ * Custom AWT event queue to trap X errors and avoid application crash.
+ */
+public class SwtAwtEventQueue extends EventQueue {
+    protected static final Logger LOGGER = Logger.getLogger(SwtAwtEventQueue.class);
+
+    /**
+     * Register SWT GDK error handler
+     */
+    public static void registerErrorHandler() {
+        OS.gdk_error_trap_push();
+    }
+
+    /**
+     * Handle errors caught by SWT GDK error handler
+     */
+    public static void handleGdkError() {
+        OS.gdk_flush();
+        int errorCode = OS.gdk_error_trap_pop();
+        if (errorCode != 0) {
+            LOGGER.debug("Uncaught GDK X error: " + errorCode);
+        }
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public void postEvent(AWTEvent event) {
+        registerErrorHandler();
+        super.postEvent(event);
+        handleGdkError();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected void dispatchEvent(AWTEvent event) {
+        registerErrorHandler();
+        super.dispatchEvent(event);
+        handleGdkError();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public AWTEvent getNextEvent() throws InterruptedException {
+        registerErrorHandler();
+        AWTEvent event = super.getNextEvent();
+        handleGdkError();
+        return event;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public synchronized AWTEvent peekEvent() {
+        registerErrorHandler();
+        AWTEvent event = super.peekEvent();
+        handleGdkError();
+        return event;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public synchronized AWTEvent peekEvent(int id) {
+        registerErrorHandler();
+        AWTEvent event = super.peekEvent(id);
+        handleGdkError();
+        return event;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected void pop() throws EmptyStackException {
+        registerErrorHandler();
+        super.pop();
+        handleGdkError();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public synchronized void push(EventQueue newEventQueue) {
+        registerErrorHandler();
+        super.push(newEventQueue);
+        handleGdkError();
+    }
+}

src/java/davmail/ui/tray/SwtGatewayTray.java

@@ -29,11 +29,14 @@ import org.apache.log4j.lf5.LF5Appender;
 import org.apache.log4j.lf5.LogLevel;
 import org.apache.log4j.lf5.viewer.LogBrokerMonitor;
 import org.eclipse.swt.SWT;
-import org.eclipse.swt.graphics.DeviceData;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.widgets.*;
+import org.eclipse.swt.widgets.Event;
+import org.eclipse.swt.widgets.Menu;
+import org.eclipse.swt.widgets.MenuItem;
 
 import javax.swing.*;
+import java.awt.*;
 import java.io.IOException;
 import java.net.URL;
 
@@ -174,20 +177,24 @@ public class SwtGatewayTray implements DavGatewayTrayInterface {
             // workaround for bug when SWT and AWT both try to access Gtk
             if (lafClassName.indexOf("gtk") > 0) {
                 lafClassName = UIManager.getCrossPlatformLookAndFeelClassName();
+                // replace AWT event queue Gdk error handler to avoid application crash
+                Toolkit.getDefaultToolkit().getSystemEventQueue().push(new SwtAwtEventQueue());
+                SwtAwtEventQueue.registerErrorHandler();
+                UIManager.setLookAndFeel(lafClassName);
+                SwtAwtEventQueue.handleGdkError();
+            } else {
+                UIManager.setLookAndFeel(lafClassName);
             }
-            UIManager.setLookAndFeel(lafClassName);
         } catch (Exception e) {
             DavGatewayTray.warn(new BundleMessage("LOG_UNABLE_TO_SET_LOOK_AND_FEEL"));
         }
 
+
         new Thread("SWT") {
             @Override
             public void run() {
                 try {
-                    DeviceData data = new DeviceData();
+                    display = new Display();
-                    data.debug = true;
-                    display = new Display(data);
-
                     shell = new Shell(display);
 
                     final Tray tray = display.getSystemTray();