| /* |
| * 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.tinkerpop.gremlin.process.traversal.step.map; |
| |
| import org.apache.commons.configuration.Configuration; |
| import org.apache.tinkerpop.gremlin.process.computer.KeyValue; |
| import org.apache.tinkerpop.gremlin.process.computer.MapReduce; |
| import org.apache.tinkerpop.gremlin.process.computer.traversal.TraversalVertexProgram; |
| import org.apache.tinkerpop.gremlin.process.traversal.Step; |
| import org.apache.tinkerpop.gremlin.process.traversal.Traversal; |
| import org.apache.tinkerpop.gremlin.process.traversal.TraversalEngine; |
| import org.apache.tinkerpop.gremlin.process.traversal.Traverser; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.EngineDependent; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.MapReducer; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.util.BulkSet; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.util.FinalGet; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.util.ReducingBarrierStep; |
| import org.apache.tinkerpop.gremlin.process.traversal.traverser.TraverserRequirement; |
| import org.apache.tinkerpop.gremlin.process.traversal.traverser.util.TraverserSet; |
| import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalHelper; |
| import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalMatrix; |
| import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalUtil; |
| import org.apache.tinkerpop.gremlin.structure.Graph; |
| import org.apache.tinkerpop.gremlin.structure.Vertex; |
| import org.apache.tinkerpop.gremlin.structure.util.StringFactory; |
| |
| import java.io.Serializable; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.function.BiFunction; |
| import java.util.function.Supplier; |
| |
| /** |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| */ |
| @Deprecated |
| public final class GroupStepV3d0<S, K, V, R> extends ReducingBarrierStep<S, Map<K, R>> implements MapReducer, EngineDependent, TraversalParent { |
| |
| private char state = 'k'; |
| |
| private Traversal.Admin<S, K> keyTraversal = null; |
| private Traversal.Admin<S, V> valueTraversal = null; |
| private Traversal.Admin<Collection<V>, R> reduceTraversal = null; |
| private boolean byPass = false; |
| |
| public GroupStepV3d0(final Traversal.Admin traversal) { |
| super(traversal); |
| this.setSeedSupplier((Supplier) new GroupMapSupplierV3d0()); |
| this.setBiFunction(new GroupBiFunction(this)); |
| } |
| |
| @Override |
| public void onEngine(final TraversalEngine traversalEngine) { |
| this.byPass = traversalEngine.isComputer(); |
| } |
| |
| @Override |
| public <A, B> List<Traversal.Admin<A, B>> getLocalChildren() { |
| final List<Traversal.Admin<A, B>> children = new ArrayList<>(3); |
| if (null != this.keyTraversal) |
| children.add((Traversal.Admin) this.keyTraversal); |
| if (null != this.valueTraversal) |
| children.add((Traversal.Admin) this.valueTraversal); |
| if (null != this.reduceTraversal) |
| children.add((Traversal.Admin) this.reduceTraversal); |
| return children; |
| } |
| |
| public Traversal.Admin<Collection<V>, R> getReduceTraversal() { |
| return this.reduceTraversal; |
| } |
| |
| @Override |
| public void addLocalChild(final Traversal.Admin<?, ?> kvrTraversal) { |
| if ('k' == this.state) { |
| this.keyTraversal = this.integrateChild(kvrTraversal); |
| this.state = 'v'; |
| } else if ('v' == this.state) { |
| this.valueTraversal = this.integrateChild(kvrTraversal); |
| this.state = 'r'; |
| } else if ('r' == this.state) { |
| this.reduceTraversal = this.integrateChild(kvrTraversal); |
| this.state = 'x'; |
| } else { |
| throw new IllegalStateException("The key, value, and reduce functions for group()-step have already been set"); |
| } |
| } |
| |
| @Override |
| public Set<TraverserRequirement> getRequirements() { |
| return this.getSelfAndChildRequirements(TraverserRequirement.SIDE_EFFECTS, TraverserRequirement.BULK); |
| } |
| |
| @Override |
| public GroupStepV3d0<S, K, V, R> clone() { |
| final GroupStepV3d0<S, K, V, R> clone = (GroupStepV3d0<S, K, V, R>) super.clone(); |
| if (null != this.keyTraversal) |
| clone.keyTraversal = clone.integrateChild(this.keyTraversal.clone()); |
| if (null != this.valueTraversal) |
| clone.valueTraversal = clone.integrateChild(this.valueTraversal.clone()); |
| if (null != this.reduceTraversal) |
| clone.reduceTraversal = clone.integrateChild(this.reduceTraversal.clone()); |
| clone.setBiFunction(new GroupBiFunction<>((GroupStepV3d0) clone)); |
| return clone; |
| } |
| |
| @Override |
| public int hashCode() { |
| int result = super.hashCode(); |
| for (final Traversal.Admin traversal : this.getLocalChildren()) { |
| result ^= traversal.hashCode(); |
| } |
| return result; |
| } |
| |
| @Override |
| public MapReduce<K, Collection<V>, K, R, Map<K, R>> getMapReduce() { |
| return new GroupMapReduceV3d0<>(this); |
| } |
| |
| @Override |
| public Traverser<Map<K, R>> processNextStart() { |
| if (this.byPass) { |
| final Traverser.Admin<S> traverser = this.starts.next(); |
| final Object[] kvPair = new Object[]{TraversalUtil.applyNullable(traverser, (Traversal.Admin<S, Map>) this.keyTraversal), TraversalUtil.applyNullable(traverser, (Traversal.Admin<S, Map>) this.valueTraversal)}; |
| return traverser.asAdmin().split(kvPair, (Step) this); |
| } else { |
| return super.processNextStart(); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return StringFactory.stepString(this, this.keyTraversal, this.valueTraversal, this.reduceTraversal); |
| } |
| |
| /////////// |
| |
| private static class GroupBiFunction<S, K, V> implements BiFunction<Map<K, Collection<V>>, Traverser.Admin<S>, Map<K, Collection<V>>>, Serializable { |
| |
| private final GroupStepV3d0<S, K, V, ?> groupStep; |
| |
| private GroupBiFunction(final GroupStepV3d0<S, K, V, ?> groupStep) { |
| this.groupStep = groupStep; |
| } |
| |
| @Override |
| public Map<K, Collection<V>> apply(final Map<K, Collection<V>> mutatingSeed, final Traverser.Admin<S> traverser) { |
| final K key = TraversalUtil.applyNullable(traverser, this.groupStep.keyTraversal); |
| final V value = TraversalUtil.applyNullable(traverser, this.groupStep.valueTraversal); |
| Collection<V> values = mutatingSeed.get(key); |
| if (null == values) { |
| values = new BulkSet<>(); |
| mutatingSeed.put(key, values); |
| } |
| TraversalHelper.addToCollectionUnrollIterator(values, value, traverser.bulk()); |
| return mutatingSeed; |
| } |
| } |
| |
| ////////// |
| |
| private class GroupMapV3d0 extends HashMap<K, Collection<V>> implements FinalGet<Map<K, R>> { |
| |
| @Override |
| public Map<K, R> getFinal() { |
| if (null == GroupStepV3d0.this.reduceTraversal) |
| return (Map<K, R>) this; |
| else { |
| final Map<K, R> reduceMap = new HashMap<>(); |
| this.forEach((k, vv) -> reduceMap.put(k, TraversalUtil.applyNullable(vv, GroupStepV3d0.this.reduceTraversal))); |
| return reduceMap; |
| } |
| } |
| } |
| |
| private class GroupMapSupplierV3d0 implements Supplier<GroupMapV3d0>, Serializable { |
| |
| private GroupMapSupplierV3d0() { |
| } |
| |
| @Override |
| public GroupMapV3d0 get() { |
| return new GroupMapV3d0(); |
| } |
| } |
| |
| /////////// |
| |
| public static final class GroupMapReduceV3d0<K, V, R> implements MapReduce<K, Collection<V>, K, R, Map<K, R>> { |
| |
| public static final String GROUP_BY_STEP_STEP_ID = "gremlin.groupStep.stepId"; |
| |
| private String groupStepId; |
| private Traversal.Admin<Collection<V>, R> reduceTraversal; |
| |
| private GroupMapReduceV3d0() { |
| |
| } |
| |
| public GroupMapReduceV3d0(final GroupStepV3d0<?, K, V, R> step) { |
| this.groupStepId = step.getId(); |
| this.reduceTraversal = step.getReduceTraversal(); |
| } |
| |
| @Override |
| public void storeState(final Configuration configuration) { |
| MapReduce.super.storeState(configuration); |
| configuration.setProperty(GROUP_BY_STEP_STEP_ID, this.groupStepId); |
| } |
| |
| @Override |
| public void loadState(final Graph graph, final Configuration configuration) { |
| this.groupStepId = configuration.getString(GROUP_BY_STEP_STEP_ID); |
| this.reduceTraversal = ((GroupStepV3d0) new TraversalMatrix<>(TraversalVertexProgram.getTraversal(graph, configuration)).getStepById(this.groupStepId)).getReduceTraversal(); |
| } |
| |
| @Override |
| public boolean doStage(final Stage stage) { |
| return !stage.equals(Stage.COMBINE); |
| } |
| |
| @Override |
| public void map(final Vertex vertex, final MapEmitter<K, Collection<V>> emitter) { |
| vertex.<TraverserSet<Object[]>>property(TraversalVertexProgram.HALTED_TRAVERSERS).ifPresent(traverserSet -> traverserSet.forEach(traverser -> { |
| final Object[] objects = traverser.get(); |
| for (int i = 0; i < traverser.bulk(); i++) { |
| if (objects[1] instanceof Collection) |
| emitter.emit((K) objects[0], (Collection<V>) objects[1]); |
| else { |
| final List<V> collection = new ArrayList<>(); |
| collection.add((V) objects[1]); |
| emitter.emit((K) objects[0], collection); |
| } |
| } |
| })); |
| } |
| |
| @Override |
| public void reduce(final K key, final Iterator<Collection<V>> values, final ReduceEmitter<K, R> emitter) { |
| final Set<V> set = new BulkSet<>(); |
| values.forEachRemaining(set::addAll); |
| emitter.emit(key, TraversalUtil.applyNullable(set, this.reduceTraversal)); |
| } |
| |
| @Override |
| public Map<K, R> generateFinalResult(final Iterator<KeyValue<K, R>> keyValues) { |
| final Map<K, R> map = new HashMap<>(); |
| keyValues.forEachRemaining(keyValue -> map.put(keyValue.getKey(), keyValue.getValue())); |
| return map; |
| } |
| |
| @Override |
| public String getMemoryKey() { |
| return REDUCING; |
| } |
| |
| @Override |
| public GroupMapReduceV3d0<K, V, R> clone() { |
| try { |
| final GroupMapReduceV3d0<K, V, R> clone = (GroupMapReduceV3d0<K, V, R>) super.clone(); |
| if (null != clone.reduceTraversal) |
| clone.reduceTraversal = this.reduceTraversal.clone(); |
| return clone; |
| } catch (final CloneNotSupportedException e) { |
| throw new IllegalStateException(e.getMessage(), e); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return StringFactory.mapReduceString(this, this.getMemoryKey()); |
| } |
| } |
| } |
