org.gradoop.flink.algorithms.fsm.transactional.tle.functions.SubgraphDecoder.java Source code

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Here is the source code for org.gradoop.flink.algorithms.fsm.transactional.tle.functions.SubgraphDecoder.java

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/**
 * Copyright  2014 - 2018 Leipzig University (Database Research Group)
 *
 * Licensed 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.gradoop.flink.algorithms.fsm.transactional.tle.functions;

import com.google.common.collect.Maps;
import com.google.common.collect.Sets;

import org.gradoop.common.model.api.entities.EPGMEdgeFactory;
import org.gradoop.common.model.api.entities.EPGMGraphHeadFactory;
import org.gradoop.common.model.api.entities.EPGMVertexFactory;
import org.gradoop.common.model.impl.id.GradoopId;
import org.gradoop.common.model.impl.id.GradoopIdSet;
import org.gradoop.common.model.impl.pojo.Edge;
import org.gradoop.common.model.impl.pojo.GraphHead;
import org.gradoop.common.model.impl.pojo.Vertex;
import org.gradoop.common.model.impl.properties.Properties;
import org.gradoop.flink.algorithms.fsm.transactional.common.TFSMConstants;
import org.gradoop.flink.algorithms.fsm.transactional.tle.pojos.FSMEdge;
import org.gradoop.flink.algorithms.fsm.transactional.tle.tuples.Subgraph;
import org.gradoop.flink.model.impl.layouts.transactional.tuples.GraphTransaction;
import org.gradoop.flink.util.GradoopFlinkConfig;

import java.io.Serializable;
import java.util.Collection;
import java.util.Map;
import java.util.Set;

/**
 * Superclass of map functions mapping FSM-fitted subgraph representations to
 * Gradoop graph transactions.
 */
public abstract class SubgraphDecoder implements Serializable {

    /**
     * graph Head Factory
     */
    protected final EPGMGraphHeadFactory<GraphHead> graphHeadFactory;
    /**
     * vertex Factory
     */
    protected final EPGMVertexFactory<Vertex> vertexFactory;
    /**
     * edge Factory
     */
    protected final EPGMEdgeFactory<Edge> edgeFactory;

    /**
     * Constructor.
     *
     * @param config Gradoop configuration
     */
    public SubgraphDecoder(GradoopFlinkConfig config) {
        vertexFactory = config.getVertexFactory();
        graphHeadFactory = config.getGraphHeadFactory();
        edgeFactory = config.getEdgeFactory();
    }

    /**
     * Turns the subgraph into a Gradoop graph transaction.
     *
     * @param subgraph subgraph
     * @param canonicalLabel canonical label
     * @return graph transaction
     */
    protected GraphTransaction createTransaction(Subgraph subgraph, String canonicalLabel) {

        // GRAPH HEAD

        Properties properties = new Properties();

        properties.set(TFSMConstants.SUPPORT_KEY, subgraph.getCount());
        properties.set(TFSMConstants.CANONICAL_LABEL_KEY, subgraph.getCanonicalLabel());

        GraphHead epgmGraphHead = graphHeadFactory.createGraphHead(canonicalLabel, properties);

        GradoopIdSet graphIds = GradoopIdSet.fromExisting(epgmGraphHead.getId());

        // VERTICES

        Map<Integer, String> vertices = subgraph.getEmbedding().getVertices();
        Set<Vertex> epgmVertices = Sets.newHashSetWithExpectedSize(vertices.size());
        Map<Integer, GradoopId> vertexIdMap = Maps.newHashMapWithExpectedSize(vertices.size());

        for (Map.Entry<Integer, String> vertex : vertices.entrySet()) {
            Vertex epgmVertex = vertexFactory.createVertex(vertex.getValue(), graphIds);

            vertexIdMap.put(vertex.getKey(), epgmVertex.getId());
            epgmVertices.add(epgmVertex);
        }

        // EDGES

        Collection<FSMEdge> edges = subgraph.getEmbedding().getEdges().values();
        Set<Edge> epgmEdges = Sets.newHashSetWithExpectedSize(edges.size());

        for (FSMEdge edge : edges) {
            epgmEdges.add(edgeFactory.createEdge(edge.getLabel(), vertexIdMap.get(edge.getSourceId()),
                    vertexIdMap.get(edge.getTargetId()), graphIds));
        }

        return new GraphTransaction(epgmGraphHead, epgmVertices, epgmEdges);
    }
}