1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache license, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the license for the specific language governing permissions and 15 * limitations under the license. 16 */ 17 package org.apache.logging.log4j.core.util; 18 19 import java.util.concurrent.ExecutorService; 20 import java.util.concurrent.TimeUnit; 21 22 import org.apache.logging.log4j.Logger; 23 import org.apache.logging.log4j.status.StatusLogger; 24 25 public class ExecutorServices { 26 27 private static final Logger LOGGER = StatusLogger.getLogger(); 28 29 /** 30 * Shuts down the given {@link ExecutorService} in an orderly fashion. Disables new tasks from submission and then 31 * waits for existing tasks to terminate. Eventually cancels running tasks if too much time elapses. 32 * <p> 33 * If the timeout is 0, then a plain shutdown takes place. 34 * </p> 35 * 36 * @param executorService 37 * the pool to shutdown. 38 * @param timeout 39 * the maximum time to wait, or 0 to not wait for existing tasks to terminate. 40 * @param timeUnit 41 * the time unit of the timeout argument 42 * @param source 43 * use this string in any log messages. 44 * @return {@code true} if the given executor terminated and {@code false} if the timeout elapsed before 45 * termination. 46 */ 47 public static boolean shutdown(final ExecutorService executorService, final long timeout, final TimeUnit timeUnit, final String source) { 48 if (executorService == null || executorService.isTerminated()) { 49 return true; 50 } 51 executorService.shutdown(); // Disable new tasks from being submitted 52 if (timeout > 0 && timeUnit == null) { 53 throw new IllegalArgumentException( 54 String.format("%s can't shutdown %s when timeout = %,d and timeUnit = %s.", source, executorService, 55 timeout, timeUnit)); 56 } 57 if (timeout > 0) { 58 try { 59 // Wait a while for existing tasks to terminate 60 if (!executorService.awaitTermination(timeout, timeUnit)) { 61 executorService.shutdownNow(); // Cancel currently executing tasks 62 // Wait a while for tasks to respond to being cancelled 63 if (!executorService.awaitTermination(timeout, timeUnit)) { 64 LOGGER.error("{} pool {} did not terminate after {} {}", source, executorService, timeout, 65 timeUnit); 66 } 67 return false; 68 } 69 } catch (final InterruptedException ie) { 70 // (Re-)Cancel if current thread also interrupted 71 executorService.shutdownNow(); 72 // Preserve interrupt status 73 Thread.currentThread().interrupt(); 74 } 75 } else { 76 executorService.shutdown(); 77 } 78 return true; 79 } 80 81 }