org.apache.giraph.partition.SimplePartition.java Source code

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Here is the source code for org.apache.giraph.partition.SimplePartition.java

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/*
 * 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.giraph.partition;

import org.apache.giraph.graph.Vertex;
import org.apache.giraph.utils.WritableUtils;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.util.Progressable;

import com.google.common.collect.Maps;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.Iterator;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ConcurrentSkipListMap;

import static org.apache.giraph.conf.GiraphConstants.USE_OUT_OF_CORE_MESSAGES;

/**
 * A simple map-based container that stores vertices.  Vertex ids will map to
 * exactly one partition.
 *
 * @param <I> Vertex id
 * @param <V> Vertex data
 * @param <E> Edge data
 * @param <M> Message data
 */
@SuppressWarnings("rawtypes")
public class SimplePartition<I extends WritableComparable, V extends Writable, E extends Writable, M extends Writable>
        extends BasicPartition<I, V, E, M> {
    /** Vertex map for this range (keyed by index) */
    private ConcurrentMap<I, Vertex<I, V, E, M>> vertexMap;

    /**
     * Constructor for reflection.
     */
    public SimplePartition() {
    }

    @Override
    public void initialize(int partitionId, Progressable progressable) {
        super.initialize(partitionId, progressable);
        if (USE_OUT_OF_CORE_MESSAGES.get(getConf())) {
            vertexMap = new ConcurrentSkipListMap<I, Vertex<I, V, E, M>>();
        } else {
            vertexMap = Maps.newConcurrentMap();
        }
    }

    @Override
    public Vertex<I, V, E, M> getVertex(I vertexIndex) {
        return vertexMap.get(vertexIndex);
    }

    @Override
    public Vertex<I, V, E, M> putVertex(Vertex<I, V, E, M> vertex) {
        return vertexMap.put(vertex.getId(), vertex);
    }

    @Override
    public Vertex<I, V, E, M> removeVertex(I vertexIndex) {
        return vertexMap.remove(vertexIndex);
    }

    @Override
    public void addPartition(Partition<I, V, E, M> partition) {
        for (Vertex<I, V, E, M> vertex : partition) {
            vertexMap.put(vertex.getId(), vertex);
        }
    }

    @Override
    public long getVertexCount() {
        return vertexMap.size();
    }

    @Override
    public long getEdgeCount() {
        long edges = 0;
        for (Vertex<I, V, E, M> vertex : vertexMap.values()) {
            edges += vertex.getNumEdges();
        }
        return edges;
    }

    @Override
    public void saveVertex(Vertex<I, V, E, M> vertex) {
        // No-op, vertices are stored as Java objects in this partition
    }

    @Override
    public String toString() {
        return "(id=" + getId() + ",V=" + vertexMap.size() + ")";
    }

    @Override
    public void readFields(DataInput input) throws IOException {
        super.readFields(input);
        if (USE_OUT_OF_CORE_MESSAGES.get(getConf())) {
            vertexMap = new ConcurrentSkipListMap<I, Vertex<I, V, E, M>>();
        } else {
            vertexMap = Maps.newConcurrentMap();
        }
        int vertices = input.readInt();
        for (int i = 0; i < vertices; ++i) {
            progress();
            Vertex<I, V, E, M> vertex = WritableUtils.readVertexFromDataInput(input, getConf());
            if (vertexMap.put(vertex.getId(), vertex) != null) {
                throw new IllegalStateException("readFields: " + this + " already has same id " + vertex);
            }
        }
    }

    @Override
    public void write(DataOutput output) throws IOException {
        super.write(output);
        output.writeInt(vertexMap.size());
        for (Vertex<I, V, E, M> vertex : vertexMap.values()) {
            progress();
            WritableUtils.writeVertexToDataOutput(output, vertex, getConf());
        }
    }

    @Override
    public Iterator<Vertex<I, V, E, M>> iterator() {
        return vertexMap.values().iterator();
    }
}