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.AtomicInteger; 027 028/** 029 * A mutable int gauge 030 */ 031@InterfaceAudience.Public 032@InterfaceStability.Evolving 033public class MutableGaugeInt extends MutableGauge { 034 035 private AtomicInteger value = new AtomicInteger(); 036 037 MutableGaugeInt(MetricsInfo info, int initValue) { 038 super(info); 039 this.value.set(initValue); 040 } 041 042 public int value() { 043 return value.get(); 044 } 045 046 @Override 047 public void incr() { 048 incr(1); 049 } 050 051 /** 052 * Increment by delta 053 * @param delta of the increment 054 */ 055 public void incr(int delta) { 056 value.addAndGet(delta); 057 setChanged(); 058 } 059 060 @Override 061 public void decr() { 062 decr(1); 063 } 064 065 /** 066 * decrement by delta 067 * @param delta of the decrement 068 */ 069 public void decr(int delta) { 070 value.addAndGet(-delta); 071 setChanged(); 072 } 073 074 /** 075 * Set the value of the metric 076 * @param value to set 077 */ 078 public void set(int value) { 079 this.value.set(value); 080 setChanged(); 081 } 082 083 @Override 084 public void snapshot(MetricsRecordBuilder builder, boolean all) { 085 if (all || changed()) { 086 builder.addGauge(info(), value()); 087 clearChanged(); 088 } 089 } 090}