1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 package org.apache.giraph.metrics; 20 21 import com.yammer.metrics.core.Gauge; 22 23 /** 24 * A Gauge that holds a value. 25 * 26 * @param <T> type of value being held. 27 */ 28 public class ValueGauge<T extends Number> extends Gauge<T> { 29 /** value held by this class */ 30 private T val; 31 32 /** 33 * Constructor that registers Gauge in MetricsRegistry. 34 * 35 * @param registry GiraphMetricsRegistry to use. 36 * @param name String name of Gauge. 37 */ 38 public ValueGauge(GiraphMetricsRegistry registry, String name) { 39 registry.getGauge(name, this); 40 } 41 42 @Override 43 public T value() { 44 return val; 45 } 46 47 /** 48 * Get double representation of value held. 49 * 50 * @return double value 51 */ 52 public double getDouble() { 53 return val != null ? val.doubleValue() : 0.0d; 54 } 55 56 /** 57 * Get long representation of value held. 58 * 59 * @return long value 60 */ 61 public long getLong() { 62 return val != null ? val.longValue() : 0L; 63 } 64 65 /** 66 * Set value held by this object. 67 * 68 * @param value value to set. 69 * @return this 70 */ 71 public ValueGauge<T> set(T value) { 72 this.val = value; 73 return this; 74 } 75 }