--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/javauis/eswt_qt/com.nokia.swt.extensions/midp/org/eclipse/ercp/swt/midp/UIThreadSupport.java	Fri Jun 11 13:33:44 2010 +0300
@@ -0,0 +1,88 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2010 Nokia Corporation and/or its subsidiary(-ies).
+ * All rights reserved. This program and the accompanying materials 
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Contributors:
+ *     Nokia Corporation - initial implementation 
+ *******************************************************************************/
+package org.eclipse.ercp.swt.midp;
+
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.internal.qt.UIThreadManager;
+
+/**
+ * <p>
+ * To use eSWT API a MIDlet needs to dedicate a thread as the UI thread for
+ * running the event loop. This can't happen in the MIDlet.startApp() because
+ * it's required by the MIDP specification that the call to startApp() returns
+ * quickly. Additionally, many native UI toolkits have restrictions for the
+ * thread that can be used as the UI thread. Thus, a random Java thread can't be
+ * used either.
+ * </p>
+ * <p>
+ * This class provides means to obtain a thread that can be used as the UI
+ * thread on the platform. All MIDlets must use this class to obtain the UI
+ * thread. If a MIDlet uses some other thread as the UI thread then the behavior
+ * is undefined.
+ * </p>
+ * 
+ * @see MIDlet
+ * @see MIDlet#startApp
+ */
+public class UIThreadSupport {
+
+private static boolean started;
+
+/**
+ * <p>
+ * Calls back the given Runnable in a thread that can be used as the UI thread.
+ * The method must not be called more than once as there might be only one
+ * thread in the process capable of being used as the UI thread.
+ * </p>
+ * 
+ * An example: <code><pre>
+ * ...
+ * class MyMIDlet extends javax.microedition.midlet.MIDlet {
+ *     ...
+ *     public void startApp() {
+ *         UIThreadSupport.startInUIThread(new Runnable() {
+ *             public void run() {
+ *                 Display display = new Display();
+ *                 ...
+ *             }
+ *          });
+ *     }
+ *     ...
+ * }
+ * </pre></code>
+ * 
+ * @param runnable The Runnable object to call back
+ * @exception SWTError <ul>
+ *                <li>ERROR_NULL_ARGUMENT if the runnable is null</li>
+ * @exception SWTError <ul>
+ *                <li>ERROR_NO_HANDLES if a handle could not be obtained for
+ *                thread creation</li>
+ * @exception SWTError <ul>
+ *                <li>ERROR_FAILED_EXEC if called more than once</li>
+ * @see MIDlet
+ * @see MIDlet#startApp
+ */
+public static void startInUIThread(Runnable runnable) {
+	if(runnable == null) {
+		SWT.error(SWT.ERROR_NULL_ARGUMENT);
+	}
+    synchronized(UIThreadSupport.class) {
+        if(started) {
+            SWT.error(SWT.ERROR_FAILED_EXEC);
+        }
+        started = true;
+    }
+    if(!UIThreadManager.startInUIThread(runnable)) {
+        SWT.error(SWT.ERROR_NO_HANDLES);
+    }
+}
+
+}