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 */ 018 019package org.apache.hadoop.metrics2.lib; 020 021import org.apache.hadoop.classification.InterfaceAudience; 022import org.apache.hadoop.classification.InterfaceStability; 023import org.apache.hadoop.metrics2.MetricsInfo; 024import org.apache.hadoop.metrics2.MetricsRecordBuilder; 025 026import java.util.concurrent.atomic.AtomicLong; 027 028/** 029 * A mutable long counter 030 */ 031@InterfaceAudience.Public 032@InterfaceStability.Evolving 033public class MutableCounterLong extends MutableCounter { 034 035 private AtomicLong value = new AtomicLong(); 036 037 MutableCounterLong(MetricsInfo info, long initValue) { 038 super(info); 039 this.value.set(initValue); 040 } 041 042 @Override 043 public void incr() { 044 incr(1); 045 } 046 047 /** 048 * Increment the value by a delta 049 * @param delta of the increment 050 */ 051 public void incr(long delta) { 052 value.addAndGet(delta); 053 setChanged(); 054 } 055 056 public long value() { 057 return value.get(); 058 } 059 060 @Override 061 public void snapshot(MetricsRecordBuilder builder, boolean all) { 062 if (all || changed()) { 063 builder.addCounter(info(), value()); 064 clearChanged(); 065 } 066 } 067 068}