hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/traversal/algorithm/strategy/TraverseStrategy.java

/*
 * 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.
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package org.apache.hugegraph.traversal.algorithm.strategy;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.BiConsumer;

import org.apache.hugegraph.HugeGraph;
import org.apache.hugegraph.backend.id.Id;
import org.apache.hugegraph.traversal.algorithm.steps.EdgeStep;
import org.apache.hugegraph.traversal.algorithm.HugeTraverser;

public interface TraverseStrategy {

    void traverseOneLayer(Map<Id, List<HugeTraverser.Node>> vertices,
                          EdgeStep step, BiConsumer<Id, EdgeStep> consumer);

    Map<Id, List<HugeTraverser.Node>> newMultiValueMap();

    Set<HugeTraverser.Path> newPathSet();

    void addNode(Map<Id, List<HugeTraverser.Node>> vertices, Id id,
                 HugeTraverser.Node node);

    void addNewVerticesToAll(Map<Id, List<HugeTraverser.Node>> newVertices,
                             Map<Id, List<HugeTraverser.Node>> targets);

    static TraverseStrategy create(boolean concurrent, HugeGraph graph) {
        return concurrent ? new ConcurrentTraverseStrategy(graph) :
                            new SingleTraverseStrategy(graph);
    }
}