org.apache.beam.runners.dataflow.internal.DataflowAggregatorTransforms.java Source code

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Here is the source code for org.apache.beam.runners.dataflow.internal.DataflowAggregatorTransforms.java

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/*
 * 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.dataflow.internal;

import com.google.common.collect.BiMap;
import com.google.common.collect.HashBiMap;
import com.google.common.collect.HashMultimap;
import com.google.common.collect.Multimap;
import java.util.Collection;
import java.util.HashSet;
import java.util.Map;
import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.transforms.Aggregator;
import org.apache.beam.sdk.transforms.AppliedPTransform;
import org.apache.beam.sdk.transforms.PTransform;

/**
 * A mapping relating {@link Aggregator}s and the {@link PTransform} in which they are used.
 */
public class DataflowAggregatorTransforms {
    private final Map<Aggregator<?, ?>, Collection<PTransform<?, ?>>> aggregatorTransforms;
    private final Multimap<PTransform<?, ?>, AppliedPTransform<?, ?, ?>> transformAppliedTransforms;
    private final BiMap<AppliedPTransform<?, ?, ?>, String> appliedStepNames;

    public DataflowAggregatorTransforms(Map<Aggregator<?, ?>, Collection<PTransform<?, ?>>> aggregatorTransforms,
            Map<AppliedPTransform<?, ?, ?>, String> transformStepNames) {
        this.aggregatorTransforms = aggregatorTransforms;
        appliedStepNames = HashBiMap.create(transformStepNames);

        transformAppliedTransforms = HashMultimap.create();
        for (AppliedPTransform<?, ?, ?> appliedTransform : transformStepNames.keySet()) {
            transformAppliedTransforms.put(appliedTransform.getTransform(), appliedTransform);
        }
    }

    /**
     * Returns true if the provided {@link Aggregator} is used in the constructing {@link Pipeline}.
     */
    public boolean contains(Aggregator<?, ?> aggregator) {
        return aggregatorTransforms.containsKey(aggregator);
    }

    /**
     * Gets the step names in which the {@link Aggregator} is used.
     */
    public Collection<String> getAggregatorStepNames(Aggregator<?, ?> aggregator) {
        Collection<String> names = new HashSet<>();
        Collection<PTransform<?, ?>> transforms = aggregatorTransforms.get(aggregator);
        for (PTransform<?, ?> transform : transforms) {
            for (AppliedPTransform<?, ?, ?> applied : transformAppliedTransforms.get(transform)) {
                names.add(appliedStepNames.get(applied));
            }
        }
        return names;
    }

    /**
     * Gets the {@link PTransform} that was assigned the provided step name.
     */
    public AppliedPTransform<?, ?, ?> getAppliedTransformForStepName(String stepName) {
        return appliedStepNames.inverse().get(stepName);
    }
}