001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.util;
019
020import org.apache.commons.logging.Log;
021import org.apache.commons.logging.LogFactory;
022
023import org.apache.hadoop.classification.InterfaceStability;
024
025@InterfaceStability.Evolving
026public class ThreadUtil {
027  
028  private static final Log LOG = LogFactory.getLog(ThreadUtil.class);
029
030  /**
031   * Cause the current thread to sleep as close as possible to the provided
032   * number of milliseconds. This method will log and ignore any
033   * {@link InterruptedException} encountered.
034   * 
035   * @param millis the number of milliseconds for the current thread to sleep
036   */
037  public static void sleepAtLeastIgnoreInterrupts(long millis) {
038    long start = Time.now();
039    while (Time.now() - start < millis) {
040      long timeToSleep = millis -
041          (Time.now() - start);
042      try {
043        Thread.sleep(timeToSleep);
044      } catch (InterruptedException ie) {
045        LOG.warn("interrupted while sleeping", ie);
046      }
047    }
048  }
049}