[#906] Fix VirtualExecutorService.awaitTermination(..) to behave like specified in the javadocs

src/main/java/org/jboss/netty/util/VirtualExecutorService.java

@@ -135,10 +135,9 @@ public class VirtualExecutorService extends AbstractExecutorService {
     public boolean awaitTermination(long timeout, TimeUnit unit)
             throws InterruptedException {
         synchronized (startStopLock) {
-            while (!isTerminated()) {
+            if (!isTerminated()) {
                 startStopLock.wait(TimeUnit.MILLISECONDS.convert(timeout, unit));
             }
-
             return isTerminated();
         }
     }

src/test/java/org/jboss/netty/util/VirtualExecutorServiceTest.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2013 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package org.jboss.netty.util;
+
+import static junit.framework.Assert.*;
+import org.junit.Test;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+
+public class VirtualExecutorServiceTest {
+
+    // https://github.com/netty/netty/issues/906
+    @Test
+    public void awaitTerminationTest() throws InterruptedException {
+        final CountDownLatch started = new CountDownLatch(1);
+        final CountDownLatch latch = new CountDownLatch(1);
+        Runnable task = new Runnable() {
+            public void run() {
+                try {
+                    started.countDown();
+                    latch.await();
+                } catch (InterruptedException e) {
+                    // ignore
+                }
+            }
+        };
+        ExecutorService executorService = Executors.newCachedThreadPool();
+        VirtualExecutorService virtualExecutorService = new VirtualExecutorService(executorService);
+        virtualExecutorService.execute(task);
+
+        started.await();
+
+        virtualExecutorService.shutdown();
+        assertFalse(virtualExecutorService.awaitTermination(1, TimeUnit.SECONDS));
+        latch.countDown();
+        assertTrue(virtualExecutorService.awaitTermination(1, TimeUnit.SECONDS));
+
+    }
+}