| /* |
| * 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.service.launcher; |
| |
| import java.lang.Thread.UncaughtExceptionHandler; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import org.apache.hadoop.classification.InterfaceAudience.Public; |
| import org.apache.hadoop.classification.InterfaceStability.Evolving; |
| import org.apache.hadoop.util.ExitUtil; |
| import org.apache.hadoop.util.ShutdownHookManager; |
| |
| /** |
| * This class is intended to be installed by calling |
| * {@link Thread#setDefaultUncaughtExceptionHandler(UncaughtExceptionHandler)} |
| * in the main entry point. |
| * |
| * The base class will always attempt to shut down the process if an Error |
| * was raised; the behavior on a standard Exception, raised outside |
| * process shutdown, is simply to log it. |
| * |
| * (Based on the class {@code YarnUncaughtExceptionHandler}) |
| */ |
| @SuppressWarnings("UseOfSystemOutOrSystemErr") |
| @Public |
| @Evolving |
| public class HadoopUncaughtExceptionHandler |
| implements UncaughtExceptionHandler { |
| |
| /** |
| * Logger. |
| */ |
| private static final Logger LOG = LoggerFactory.getLogger( |
| HadoopUncaughtExceptionHandler.class); |
| |
| /** |
| * Delegate for simple exceptions. |
| */ |
| private final UncaughtExceptionHandler delegate; |
| |
| /** |
| * Create an instance delegating to the supplied handler if |
| * the exception is considered "simple". |
| * @param delegate a delegate exception handler. |
| */ |
| public HadoopUncaughtExceptionHandler(UncaughtExceptionHandler delegate) { |
| this.delegate = delegate; |
| } |
| |
| /** |
| * Basic exception handler -logs simple exceptions, then continues. |
| */ |
| public HadoopUncaughtExceptionHandler() { |
| this(null); |
| } |
| |
| /** |
| * Uncaught exception handler. |
| * If an error is raised: shutdown |
| * The state of the system is unknown at this point -attempting |
| * a clean shutdown is dangerous. Instead: exit |
| * @param thread thread that failed |
| * @param exception the raised exception |
| */ |
| @Override |
| public void uncaughtException(Thread thread, Throwable exception) { |
| if (ShutdownHookManager.get().isShutdownInProgress()) { |
| LOG.error("Thread {} threw an error during shutdown: {}.", |
| thread.toString(), |
| exception, |
| exception); |
| } else if (exception instanceof Error) { |
| try { |
| LOG.error("Thread {} threw an error: {}. Shutting down", |
| thread.toString(), |
| exception, |
| exception); |
| } catch (Throwable err) { |
| // We don't want to not exit because of an issue with logging |
| } |
| if (exception instanceof OutOfMemoryError) { |
| // After catching an OOM java says it is undefined behavior, so don't |
| // even try to clean up or we can get stuck on shutdown. |
| try { |
| System.err.println("Halting due to Out Of Memory Error..."); |
| } catch (Throwable err) { |
| // Again we don't want to exit because of logging issues. |
| } |
| ExitUtil.haltOnOutOfMemory((OutOfMemoryError) exception); |
| } else { |
| // error other than OutOfMemory |
| ExitUtil.ExitException ee = |
| ServiceLauncher.convertToExitException(exception); |
| ExitUtil.terminate(ee.status, ee); |
| } |
| } else { |
| // simple exception in a thread. There's a policy decision here: |
| // terminate the process vs. keep going after a thread has failed |
| // base implementation: do nothing but log |
| LOG.error("Thread {} threw an exception: {}", |
| thread.toString(), |
| exception, |
| exception); |
| if (delegate != null) { |
| delegate.uncaughtException(thread, exception); |
| } |
| } |
| |
| } |
| |
| } |