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 */ 018 019 package org.apache.hadoop.metrics2.lib; 020 021 import java.lang.reflect.Method; 022 import java.util.Set; 023 024 import static com.google.common.base.Preconditions.*; 025 import com.google.common.collect.Sets; 026 027 import org.apache.commons.logging.Log; 028 import org.apache.commons.logging.LogFactory; 029 030 import org.apache.hadoop.classification.InterfaceAudience; 031 import org.apache.hadoop.classification.InterfaceStability; 032 import org.apache.hadoop.metrics2.MetricsRecordBuilder; 033 034 /** 035 * Helper class to manage a group of mutable rate metrics 036 */ 037 @InterfaceAudience.Public 038 @InterfaceStability.Evolving 039 public class MutableRates extends MutableMetric { 040 static final Log LOG = LogFactory.getLog(MutableRates.class); 041 private final MetricsRegistry registry; 042 private final Set<Class<?>> protocolCache = Sets.newHashSet(); 043 044 MutableRates(MetricsRegistry registry) { 045 this.registry = checkNotNull(registry, "metrics registry"); 046 } 047 048 /** 049 * Initialize the registry with all the methods in a protocol 050 * so they all show up in the first snapshot. 051 * Convenient for JMX implementations. 052 * @param protocol the protocol class 053 */ 054 public void init(Class<?> protocol) { 055 if (protocolCache.contains(protocol)) return; 056 protocolCache.add(protocol); 057 for (Method method : protocol.getDeclaredMethods()) { 058 String name = method.getName(); 059 LOG.debug(name); 060 try { registry.newRate(name, name, false, true); } 061 catch (Exception e) { 062 LOG.error("Error creating rate metrics for "+ method.getName(), e); 063 } 064 } 065 } 066 067 /** 068 * Add a rate sample for a rate metric 069 * @param name of the rate metric 070 * @param elapsed time 071 */ 072 public void add(String name, long elapsed) { 073 registry.add(name, elapsed); 074 } 075 076 @Override 077 public void snapshot(MetricsRecordBuilder rb, boolean all) { 078 registry.snapshot(rb, all); 079 } 080 }