| /* |
| * 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.hugegraph.traversal.algorithm; |
| |
| import java.util.Iterator; |
| import java.util.Set; |
| import java.util.function.Consumer; |
| |
| import org.apache.hugegraph.HugeException; |
| import org.apache.hugegraph.HugeGraph; |
| import org.apache.hugegraph.backend.id.Id; |
| import org.apache.hugegraph.structure.HugeEdge; |
| import org.apache.hugegraph.traversal.algorithm.records.KoutRecords; |
| import org.apache.hugegraph.traversal.algorithm.steps.EdgeStep; |
| import org.apache.hugegraph.type.define.Directions; |
| import org.apache.hugegraph.util.E; |
| import org.apache.tinkerpop.gremlin.structure.Edge; |
| |
| public class KoutTraverser extends OltpTraverser { |
| |
| public KoutTraverser(HugeGraph graph) { |
| super(graph); |
| } |
| |
| public Set<Id> kout(Id sourceV, Directions dir, String label, |
| int depth, boolean nearest, |
| long degree, long capacity, long limit) { |
| E.checkNotNull(sourceV, "source vertex id"); |
| this.checkVertexExist(sourceV, "source vertex"); |
| E.checkNotNull(dir, "direction"); |
| checkPositive(depth, "k-out max_depth"); |
| checkDegree(degree); |
| checkCapacity(capacity); |
| checkLimit(limit); |
| if (capacity != NO_LIMIT) { |
| // Capacity must > limit because sourceV is counted in capacity |
| E.checkArgument(capacity >= limit && limit != NO_LIMIT, |
| "Capacity can't be less than limit, " + |
| "but got capacity '%s' and limit '%s'", |
| capacity, limit); |
| } |
| |
| Id labelId = this.getEdgeLabelId(label); |
| |
| Set<Id> latest = newIdSet(); |
| latest.add(sourceV); |
| |
| Set<Id> all = newIdSet(); |
| all.add(sourceV); |
| |
| long remaining = capacity == NO_LIMIT ? |
| NO_LIMIT : capacity - latest.size(); |
| this.vertexIterCounter.addAndGet(1L); |
| while (depth-- > 0) { |
| // Just get limit nodes in last layer if limit < remaining capacity |
| if (depth == 0 && limit != NO_LIMIT && |
| (limit < remaining || remaining == NO_LIMIT)) { |
| remaining = limit; |
| } |
| if (nearest) { |
| latest = this.adjacentVertices(sourceV, latest, dir, labelId, |
| all, degree, remaining); |
| all.addAll(latest); |
| } else { |
| latest = this.adjacentVertices(sourceV, latest, dir, labelId, |
| null, degree, remaining); |
| } |
| this.vertexIterCounter.addAndGet(1L); |
| this.edgeIterCounter.addAndGet(latest.size()); |
| if (capacity != NO_LIMIT) { |
| // Update 'remaining' value to record remaining capacity |
| remaining -= latest.size(); |
| |
| if (remaining <= 0 && depth > 0) { |
| throw new HugeException( |
| "Reach capacity '%s' while remaining depth '%s'", |
| capacity, depth); |
| } |
| } |
| } |
| |
| return latest; |
| } |
| |
| public KoutRecords customizedKout(Id source, EdgeStep step, |
| int maxDepth, boolean nearest, |
| long capacity, long limit) { |
| E.checkNotNull(source, "source vertex id"); |
| this.checkVertexExist(source, "source vertex"); |
| checkPositive(maxDepth, "k-out max_depth"); |
| checkCapacity(capacity); |
| checkLimit(limit); |
| long[] depth = new long[1]; |
| depth[0] = maxDepth; |
| boolean concurrent = maxDepth >= this.concurrentDepth(); |
| |
| KoutRecords records = new KoutRecords(concurrent, source, nearest); |
| |
| Consumer<Id> consumer = v -> { |
| if (this.reachLimit(limit, depth[0], records.size())) { |
| return; |
| } |
| Iterator<Edge> edges = edgesOfVertex(v, step); |
| this.vertexIterCounter.addAndGet(1L); |
| while (!this.reachLimit(limit, depth[0], records.size()) && |
| edges.hasNext()) { |
| HugeEdge edge = (HugeEdge) edges.next(); |
| Id target = edge.id().otherVertexId(); |
| records.addPath(v, target); |
| this.checkCapacity(capacity, records.accessed(), depth[0]); |
| |
| records.edgeResults().addEdge(v, target, edge); |
| |
| this.edgeIterCounter.addAndGet(1L); |
| } |
| }; |
| |
| while (depth[0]-- > 0) { |
| records.startOneLayer(true); |
| this.traverseIds(records.keys(), consumer, concurrent); |
| records.finishOneLayer(); |
| } |
| return records; |
| } |
| |
| private void checkCapacity(long capacity, long accessed, long depth) { |
| if (capacity == NO_LIMIT) { |
| return; |
| } |
| if (accessed >= capacity && depth > 0) { |
| throw new HugeException( |
| "Reach capacity '%s' while remaining depth '%s'", |
| capacity, depth); |
| } |
| } |
| |
| private boolean reachLimit(long limit, long depth, int size) { |
| return limit != NO_LIMIT && depth <= 0 && size >= limit; |
| } |
| } |