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.hbase.util;
019
020import java.util.concurrent.atomic.AtomicLong;
021
022import org.apache.yetus.audience.InterfaceAudience;
023
024/**
025 * Utilities related to atomic operations.
026 */
027@InterfaceAudience.Private
028public final class AtomicUtils {
029  private AtomicUtils() {
030  }
031
032  /**
033   * Updates a AtomicLong which is supposed to maintain the minimum values. This method is not
034   * synchronized but is thread-safe.
035   */
036  public static void updateMin(AtomicLong min, long value) {
037    while (true) {
038      long cur = min.get();
039      if (value >= cur) {
040        break;
041      }
042
043      if (min.compareAndSet(cur, value)) {
044        break;
045      }
046    }
047  }
048
049  /**
050   * Updates a AtomicLong which is supposed to maintain the maximum values. This method is not
051   * synchronized but is thread-safe.
052   */
053  public static void updateMax(AtomicLong max, long value) {
054    while (true) {
055      long cur = max.get();
056      if (value <= cur) {
057        break;
058      }
059
060      if (max.compareAndSet(cur, value)) {
061        break;
062      }
063    }
064  }
065}