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 gobblin.util; import java.util.Collection; import java.util.Map; import lombok.AllArgsConstructor; import lombok.Getter; import com.google.common.base.Predicate; import com.google.common.collect.ArrayListMultimap; import com.google.common.collect.Iterables; import com.google.common.collect.Multimap; import gobblin.configuration.WorkUnitState; import gobblin.configuration.WorkUnitState.WorkingState; import gobblin.publisher.DataPublisher; import gobblin.source.workunit.Extract; /** * Utility class for {@link DataPublisher}. */ public class PublisherUtils { /** * Creates a {@link Multimap} that maps {@link Extract} to their corresponds {@link WorkUnitState}s. * * @see Multimap */ public static Multimap<Extract, WorkUnitState> createExtractToWorkUnitStateMap( Collection<? extends WorkUnitState> workUnitStates) { Multimap<Extract, WorkUnitState> extractToWorkUnitStateMap = ArrayListMultimap.create(); for (WorkUnitState workUnitState : workUnitStates) { extractToWorkUnitStateMap.put(workUnitState.getExtract(), workUnitState); } return extractToWorkUnitStateMap; } /** * Given a {@link Multimap} of {@link Extract}s to {@link WorkUnitState}s, filter out any {@link Extract}s where all * of the corresponding {@link WorkUnitState}s do not meet the given {@link Predicate}. */ public static Multimap<Extract, WorkUnitState> getExtractsForPredicate( Multimap<Extract, WorkUnitState> extractToWorkUnitStateMap, Predicate<WorkUnitState> predicate) { Multimap<Extract, WorkUnitState> successfulExtracts = ArrayListMultimap.create(); for (Map.Entry<Extract, Collection<WorkUnitState>> entry : extractToWorkUnitStateMap.asMap().entrySet()) { if (Iterables.all(entry.getValue(), predicate)) { successfulExtracts.putAll(entry.getKey(), entry.getValue()); } } return successfulExtracts; } /** * Given a {@link Multimap} of {@link Extract}s to {@link WorkUnitState}s, filter out any {@link Extract}s where all * of the corresponding {@link WorkUnitState}s do not meet the given {@link Predicate}. * <ul> * <li> The filtered {@link Extract}s will be available in {@link SplitExtractsResult#getFiltered()}</li> * <li> The {@link Extract}s satisfying the predicated will be available in {@link SplitExtractsResult#getRetained()}</li> * </ul> * */ public static SplitExtractsResult splitExtractsByPredicate( Multimap<Extract, WorkUnitState> extractToWorkUnitStateMap, Predicate<WorkUnitState> predicate) { Multimap<Extract, WorkUnitState> retained = ArrayListMultimap.create(); Multimap<Extract, WorkUnitState> filtered = ArrayListMultimap.create(); for (Map.Entry<Extract, Collection<WorkUnitState>> entry : extractToWorkUnitStateMap.asMap().entrySet()) { if (Iterables.all(entry.getValue(), predicate)) { retained.putAll(entry.getKey(), entry.getValue()); } else { filtered.putAll(entry.getKey(), entry.getValue()); } } return new SplitExtractsResult(retained, filtered); } /** * Implementation of {@link Predicate} that checks if a given {@link WorkUnitState} has a {@link WorkingState} equal * to {@link WorkingState#SUCCESSFUL}. */ public static class WorkUnitStateSuccess implements Predicate<WorkUnitState> { @Override public boolean apply(WorkUnitState workUnitState) { return workUnitState.getWorkingState().equals(WorkingState.SUCCESSFUL); } } @AllArgsConstructor @Getter public static class SplitExtractsResult { private Multimap<Extract, WorkUnitState> retained; private Multimap<Extract, WorkUnitState> filtered; } }