| // Copyright 2016 Twitter. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.twitter.heron.api.metric; |
| |
| import java.io.Serializable; |
| |
| /** |
| * Singleton class which exposes a simple globally available counter for heron jobs. |
| * Anywhere in the execution of heron job, user can put- |
| * <code>GlobalMetrics.incr("mycounter")</code> to add a counter. There will be no need to |
| * explicitly declare the counter before. If the counter doesn't exist it will be created. |
| * The creation is lazy which means, unless the counter not being available, it is counted as 0 |
| * CounterFactory.init() should be called in prepare and open methods of bolt and spout respectively. |
| * The counters will be named __auto__/mycounter (note the __auto__ prefix) |
| */ |
| public enum GlobalMetrics implements Serializable { |
| INSTANCE; |
| public static final String ROOT_NAME = "__auto__"; |
| private MultiCountMetric metricsContainer; |
| private boolean registered; |
| |
| GlobalMetrics() { |
| metricsContainer = new MultiCountMetric(); |
| registered = false; |
| } |
| |
| /** |
| * Not thread safe increment of counterName. Counter doesn't exist unless incremented once |
| */ |
| public static void incr(String counterName) { |
| INSTANCE.metricsContainer.scope(counterName).incr(); |
| } |
| |
| /** |
| * Not thread safe 'incrementing by' of counterName. Counter doesn't exist unless incremented once |
| */ |
| public static void incrBy(String counterName, int incrValue) { |
| INSTANCE.metricsContainer.scope(counterName).incrBy(incrValue); |
| } |
| |
| /** |
| * Thread safe created increment of counterName. (Slow) |
| */ |
| public static void safeIncr(String counterName) { |
| synchronized (INSTANCE) { |
| if (INSTANCE.registered) { |
| INSTANCE.metricsContainer.scope(counterName).incr(); |
| } |
| } |
| } |
| |
| /** |
| * Thread safe created increment of counterName. (Slow) |
| */ |
| public static void safeIncrBy(String counterName, int incrValue) { |
| synchronized (INSTANCE) { |
| if (INSTANCE.registered) { |
| INSTANCE.metricsContainer.scope(counterName).incrBy(incrValue); |
| } |
| } |
| } |
| |
| /** |
| * Initialize the counter by registering the metricContainer. Should be done in open/prepare call. |
| * TODO: Investigate if it is possible to do this part in ctor. One thing to note is how this will |
| * affect the serialization of CounterFactory. |
| */ |
| public static void init(IMetricsRegister metricsRegister, int metricsBucket) { |
| synchronized (INSTANCE) { |
| if (!INSTANCE.registered) { |
| metricsRegister.registerMetric(ROOT_NAME, INSTANCE.metricsContainer, metricsBucket); |
| INSTANCE.registered = true; |
| } |
| } |
| } |
| |
| /** |
| * test-only |
| */ |
| public static MultiCountMetric getUnderlyingCounter() { |
| return INSTANCE.metricsContainer; |
| } |
| |
| /** |
| * During serialization don't create a copy of this class. 'readResolve' is used by reflection |
| * for java serialization. |
| */ |
| protected Object readResolve() { |
| return INSTANCE; |
| } |
| } |