| /** |
| * 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.hbase.util; |
| |
| |
| /** |
| * This class provides ShutdownHookManager shims for HBase to interact with the Hadoop 1.0.x and the |
| * Hadoop 2.0+ series. |
| * |
| * NOTE: No testing done against 0.22.x, or 0.21.x. |
| */ |
| abstract public class ShutdownHookManager { |
| private static ShutdownHookManager instance; |
| |
| static Class shutdownHookManagerClass = null; |
| static { |
| try { |
| // This class exists in hadoop 2.0+ but not in Hadoop 20.x/1.x |
| shutdownHookManagerClass = Class.forName("org.apache.hadoop.util.ShutdownHookManager"); |
| instance = new ShutdownHookManagerV2(); |
| } catch (Exception e) { |
| instance = new ShutdownHookManagerV1(); |
| } |
| } |
| |
| abstract public void addShutdownHook(Thread shutdownHook, int priority); |
| |
| abstract public boolean removeShutdownHook(Runnable shutdownHook); |
| |
| public static void affixShutdownHook(Thread shutdownHook, int priority) { |
| instance.addShutdownHook(shutdownHook, priority); |
| } |
| |
| public static boolean deleteShutdownHook(Runnable shutdownHook) { |
| return instance.removeShutdownHook(shutdownHook); |
| } |
| |
| private static class ShutdownHookManagerV1 extends ShutdownHookManager { |
| // priority is ignored in hadoop versions earlier than 2.0 |
| public void addShutdownHook(Thread shutdownHookThread, int priority) { |
| Runtime.getRuntime().addShutdownHook(shutdownHookThread); |
| } |
| |
| public boolean removeShutdownHook(Runnable shutdownHook) { |
| Thread shutdownHookThread = null; |
| if (!(shutdownHook instanceof Thread)) { |
| shutdownHookThread = new Thread(shutdownHook); |
| } else shutdownHookThread = (Thread) shutdownHook; |
| |
| return Runtime.getRuntime().removeShutdownHook(shutdownHookThread); |
| } |
| }; |
| |
| private static class ShutdownHookManagerV2 extends ShutdownHookManager { |
| public void addShutdownHook(Thread shutdownHookThread, int priority) { |
| try { |
| Methods.call(shutdownHookManagerClass, |
| Methods.call(shutdownHookManagerClass, null, "get", null, null), |
| "addShutdownHook", |
| new Class[] { Runnable.class, int.class }, |
| new Object[] { shutdownHookThread, priority }); |
| } catch (Exception ex) { |
| throw new RuntimeException("we could not use ShutdownHookManager.addShutdownHook", ex); |
| } |
| } |
| |
| public boolean removeShutdownHook(Runnable shutdownHook) { |
| try { |
| return (Boolean) |
| Methods.call(shutdownHookManagerClass, |
| Methods.call(shutdownHookManagerClass, null, "get", null, null), |
| "removeShutdownHook", |
| new Class[] { Runnable.class }, |
| new Object[] { shutdownHook }); |
| } catch (Exception ex) { |
| throw new RuntimeException("we could not use ShutdownHookManager", ex); |
| } |
| } |
| }; |
| |
| } |