Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 org.apache.beam.runners.core.metrics; import com.google.auto.value.AutoValue; import com.google.common.collect.Iterables; import java.io.Serializable; import java.util.Collections; import org.apache.beam.sdk.annotations.Experimental; import org.apache.beam.sdk.annotations.Experimental.Kind; /** * Representation of multiple metric updates. */ @Experimental(Kind.METRICS) @AutoValue public abstract class MetricUpdates { public static final MetricUpdates EMPTY = MetricUpdates.create(Collections.<MetricUpdate<Long>>emptyList(), Collections.<MetricUpdate<DistributionData>>emptyList(), Collections.<MetricUpdate<GaugeData>>emptyList()); /** * Representation of a single metric update. * @param <T> The type of value representing the update. */ @AutoValue public abstract static class MetricUpdate<T> implements Serializable { /** The key being updated. */ public abstract MetricKey getKey(); /** The value of the update. */ public abstract T getUpdate(); public static <T> MetricUpdate<T> create(MetricKey key, T update) { return new AutoValue_MetricUpdates_MetricUpdate(key, update); } } /** Returns true if there are no updates in this MetricUpdates object. */ public boolean isEmpty() { return Iterables.isEmpty(counterUpdates()) && Iterables.isEmpty(distributionUpdates()); } /** All of the counter updates. */ public abstract Iterable<MetricUpdate<Long>> counterUpdates(); /** All of the distribution updates. */ public abstract Iterable<MetricUpdate<DistributionData>> distributionUpdates(); /** All of the gauges updates. */ public abstract Iterable<MetricUpdate<GaugeData>> gaugeUpdates(); /** Create a new {@link MetricUpdates} bundle. */ public static MetricUpdates create(Iterable<MetricUpdate<Long>> counterUpdates, Iterable<MetricUpdate<DistributionData>> distributionUpdates, Iterable<MetricUpdate<GaugeData>> gaugeUpdates) { return new AutoValue_MetricUpdates(counterUpdates, distributionUpdates, gaugeUpdates); } }