com.chinamobile.bcbsp.examples.bytearray.pagerank.PRBSPNew.java Source code

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Here is the source code for com.chinamobile.bcbsp.examples.bytearray.pagerank.PRBSPNew.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 com.chinamobile.bcbsp.examples.bytearray.pagerank;

import com.chinamobile.bcbsp.api.BSP;
import com.chinamobile.bcbsp.api.Edge;
import com.chinamobile.bcbsp.bspstaff.BSPStaffContextInterface;
import com.chinamobile.bcbsp.bspstaff.Staff;
import com.chinamobile.bcbsp.bspstaff.SuperStepContextInterface;

import java.util.Iterator;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * BSP program of PageRnak.
 *
 */
public class PRBSPNew extends BSP<PageRankMessage> {
    /** New vertex value */
    public static final Log LOG = LogFactory.getLog(PRBSPNew.class);
    /** New vertex value */
    public static final double CLICK_RP = 0.0001;
    /** New vertex value */
    public static final double FACTOR = 0.15;
    // Variables of the Graph.
    /** New vertex value */
    private float newVertexValue = 0.0f;
    /** New vertex value */
    private float receivedMsgValue = 0.0f;
    /** New vertex value */
    private float receivedMsgSum = 0.0f;
    /** New vertex value */
    private float sendMsgValue = 0.0f;
    /** New vertex value */
    private Iterator<Edge> outgoingEdges;
    /** New vertex value */
    private PREdgeLiteNew edge;
    /** New vertex value */
    private PageRankMessage msg;
    /** New vertex value */
    private int failCounter = 0;

    @Override
    public void setup(Staff staff) {
        this.failCounter = staff.getFailCounter();
    }

    @Override
    public void initBeforeSuperStep(SuperStepContextInterface arg0) {
    }

    @Override
    public void compute(Iterator<PageRankMessage> messages, BSPStaffContextInterface context) throws Exception {
        // Receive messages sent to this Vertex.
        //LOG.info("Vertex is processed! PRBSPNew");
        receivedMsgValue = 0.0f;
        receivedMsgSum = 0.0f;
        int i = 0;
        while (messages.hasNext()) {
            // Note Modified
            i++;
            receivedMsgValue = (messages.next()).getContent();
            receivedMsgSum += receivedMsgValue;
        }
        PRVertexLiteNew vertex = (PRVertexLiteNew) context.getVertex();
        // Handle received messages and Update vertex value.
        if (context.getCurrentSuperStepCounter() == 0) {
            sendMsgValue = Float.valueOf(vertex.getVertexValue()) / context.getOutgoingEdgesNum(); // old vertex value
        } else {
            newVertexValue = (float) (CLICK_RP * FACTOR + receivedMsgSum * (1 - FACTOR));
            sendMsgValue = newVertexValue / context.getOutgoingEdgesNum();
            vertex.setVertexValue(newVertexValue);
            context.updateVertex(vertex);
        }
        // Send new messages.
        outgoingEdges = context.getOutgoingEdges();
        while (outgoingEdges.hasNext()) {
            edge = (PREdgeLiteNew) outgoingEdges.next();
            // Note Improved For Message Reuse.
            msg = (PageRankMessage) context.getMessage();
            msg.setContent(sendMsgValue);
            msg.setMessageId(edge.getVertexID());
            context.send(msg);
        }
        return;
    }
}