HADOOP-9787. ShutdownHelper util to shutdown threads and threadpools. (Karthik Kambatla via Sandy Ryza)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1509053 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -41,6 +41,9 @@ Release 2.1.1-beta - UNRELEASED
 
   IMPROVEMENTS
  
+    HADOOP-9787. ShutdownHelper util to shutdown threads and threadpools.
+    (Karthik Kambatla via Sandy Ryza)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/ShutdownThreadsHelper.java

@@ -0,0 +1,106 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF 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.apache.hadoop.util;
+
+import com.google.common.annotations.VisibleForTesting;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Helper class to shutdown {@link Thread}s and {@link ExecutorService}s.
+ */
+public class ShutdownThreadsHelper {
+  private static Log LOG = LogFactory.getLog(ShutdownThreadsHelper.class);
+
+  @VisibleForTesting
+  static final int SHUTDOWN_WAIT_MS = 3000;
+
+  /**
+   * @param thread {@link Thread to be shutdown}
+   * @return <tt>true</tt> if the thread is successfully interrupted,
+   * <tt>false</tt> otherwise
+   * @throws InterruptedException
+   */
+  public static boolean shutdownThread(Thread thread) {
+    return shutdownThread(thread, SHUTDOWN_WAIT_MS);
+  }
+
+  /**
+   * @param thread {@link Thread to be shutdown}
+   * @param timeoutInMilliSeconds time to wait for thread to join after being
+   *                              interrupted
+   * @return <tt>true</tt> if the thread is successfully interrupted,
+   * <tt>false</tt> otherwise
+   * @throws InterruptedException
+   */
+  public static boolean shutdownThread(Thread thread,
+                                    long timeoutInMilliSeconds) {
+    if (thread == null) {
+      return true;
+    }
+
+    try {
+      thread.interrupt();
+      thread.join(timeoutInMilliSeconds);
+      return true;
+    } catch (InterruptedException ie) {
+      LOG.warn("Interrupted while shutting down thread - " + thread.getName());
+      return false;
+    }
+  }
+
+  /**
+   * @param service {@link ExecutorService to be shutdown}
+   * @return <tt>true</tt> if the service is terminated,
+   * <tt>false</tt> otherwise
+   * @throws InterruptedException
+   */
+  public static boolean shutdownExecutorService(ExecutorService service)
+      throws InterruptedException {
+    return shutdownExecutorService(service, SHUTDOWN_WAIT_MS);
+  }
+
+  /**
+   * @param service {@link ExecutorService to be shutdown}
+   * @param timeoutInMs time to wait for {@link
+   * ExecutorService#awaitTermination(long, java.util.concurrent.TimeUnit)}
+   *                    calls in milli seconds.
+   * @return <tt>true</tt> if the service is terminated,
+   * <tt>false</tt> otherwise
+   * @throws InterruptedException
+   */
+  public static boolean shutdownExecutorService(ExecutorService service,
+                                        long timeoutInMs)
+      throws InterruptedException {
+    if (service == null) {
+      return true;
+    }
+
+    service.shutdown();
+    if (!service.awaitTermination(timeoutInMs, TimeUnit.MILLISECONDS)) {
+      service.shutdownNow();
+      return service.awaitTermination(timeoutInMs, TimeUnit.MILLISECONDS);
+    } else {
+      return true;
+    }
+  }
+}

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/TestShutdownThreadsHelper.java

@@ -0,0 +1,58 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF 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.apache.hadoop.util;
+
+import org.junit.Test;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class TestShutdownThreadsHelper {
+  private Runnable sampleRunnable = new Runnable() {
+    @Override
+    public void run() {
+      try {
+        Thread.sleep(2 * ShutdownThreadsHelper.SHUTDOWN_WAIT_MS);
+      } catch (InterruptedException ie)  {
+        System.out.println("Thread interrupted");
+      }
+    }
+  };
+
+  @Test (timeout = 3000)
+  public void testShutdownThread() {
+    Thread thread = new Thread(sampleRunnable);
+    thread.start();
+    boolean ret = ShutdownThreadsHelper.shutdownThread(thread);
+    boolean isTerminated = !thread.isAlive();
+    assertEquals("Incorrect return value", ret, isTerminated);
+    assertTrue("Thread is not shutdown", isTerminated);
+
+  }
+
+  @Test
+  public void testShutdownThreadPool() throws InterruptedException {
+    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(1);
+    executor.execute(sampleRunnable);
+    boolean ret = ShutdownThreadsHelper.shutdownExecutorService(executor);
+    boolean isTerminated = executor.isTerminated();
+    assertEquals("Incorrect return value", ret, isTerminated);
+    assertTrue("ExecutorService is not shutdown", isTerminated);
+  }
+}