| /* |
| * 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.lambda; |
| |
| import org.apache.tinkerpop.gremlin.process.traversal.Step; |
| import org.apache.tinkerpop.gremlin.process.traversal.Traversal; |
| import org.apache.tinkerpop.gremlin.process.traversal.TraversalSideEffects; |
| import org.apache.tinkerpop.gremlin.process.traversal.TraversalStrategies; |
| import org.apache.tinkerpop.gremlin.process.traversal.Traverser; |
| import org.apache.tinkerpop.gremlin.process.traversal.TraverserGenerator; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent; |
| import org.apache.tinkerpop.gremlin.process.traversal.step.util.EmptyStep; |
| import org.apache.tinkerpop.gremlin.process.traversal.traverser.B_O_TraverserGenerator; |
| import org.apache.tinkerpop.gremlin.process.traversal.traverser.TraverserRequirement; |
| import org.apache.tinkerpop.gremlin.process.traversal.util.EmptyTraversalSideEffects; |
| import org.apache.tinkerpop.gremlin.process.traversal.util.EmptyTraversalStrategies; |
| import org.apache.tinkerpop.gremlin.structure.Graph; |
| |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Optional; |
| import java.util.Set; |
| |
| /** |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| */ |
| public abstract class AbstractLambdaTraversal<S, E> implements Traversal.Admin<S, E> { |
| |
| private static final Set<TraverserRequirement> REQUIREMENTS = Collections.singleton(TraverserRequirement.OBJECT); |
| |
| public List<Step> getSteps() { |
| return Collections.emptyList(); |
| } |
| |
| @Override |
| public void reset() { |
| |
| } |
| |
| @Override |
| public <S2, E2> Traversal.Admin<S2, E2> addStep(final int index, final Step<?, ?> step) throws IllegalStateException { |
| return (Traversal.Admin<S2, E2>) this; |
| } |
| |
| @Override |
| public <S2, E2> Traversal.Admin<S2, E2> removeStep(final int index) throws IllegalStateException { |
| return (Traversal.Admin<S2, E2>) this; |
| } |
| |
| @Override |
| public void applyStrategies() throws IllegalStateException { |
| |
| } |
| |
| @Override |
| public TraverserGenerator getTraverserGenerator() { |
| return B_O_TraverserGenerator.instance(); |
| } |
| |
| @Override |
| public void setSideEffects(final TraversalSideEffects sideEffects) { |
| |
| } |
| |
| @Override |
| public TraversalSideEffects getSideEffects() { |
| return EmptyTraversalSideEffects.instance(); |
| } |
| |
| @Override |
| public void setStrategies(final TraversalStrategies strategies) { |
| |
| } |
| |
| @Override |
| public TraversalStrategies getStrategies() { |
| return EmptyTraversalStrategies.instance(); |
| } |
| |
| @Override |
| public void setParent(final TraversalParent step) { |
| |
| } |
| |
| @Override |
| public TraversalParent getParent() { |
| return EmptyStep.instance(); |
| } |
| |
| @Override |
| public Traversal.Admin<S, E> clone() { |
| try { |
| return (AbstractLambdaTraversal<S, E>) super.clone(); |
| } catch (final CloneNotSupportedException e) { |
| throw new IllegalStateException(e.getMessage(), e); |
| } |
| } |
| |
| @Override |
| public E next() { |
| throw new UnsupportedOperationException("The " + this.getClass().getSimpleName() + " can only be used as a predicate traversal"); |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return true; |
| } |
| |
| @Override |
| public void addStart(final Traverser.Admin<S> start) { |
| } |
| |
| @Override |
| public boolean isLocked() { |
| return true; |
| } |
| |
| @Override |
| public Optional<Graph> getGraph() { |
| return Optional.empty(); |
| } |
| |
| @Override |
| public void setGraph(final Graph graph) { |
| |
| } |
| |
| @Override |
| public Set<TraverserRequirement> getTraverserRequirements() { |
| return REQUIREMENTS; |
| } |
| |
| @Override |
| public int hashCode() { |
| return this.getClass().hashCode(); |
| } |
| |
| @Override |
| public boolean equals(final Object object) { |
| return this.getClass().equals(object.getClass()) && this.hashCode() == object.hashCode(); |
| } |
| |
| } |