com.chinamobile.bcbsp.partition.RecordParseDefault.java Source code

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Here is the source code for com.chinamobile.bcbsp.partition.RecordParseDefault.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.partition;

import java.util.StringTokenizer;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.Text;

import com.chinamobile.bcbsp.Constants;
import com.chinamobile.bcbsp.api.RecordParse;
import com.chinamobile.bcbsp.api.Vertex;
import com.chinamobile.bcbsp.util.BSPJob;

/**
 * RecordParseDefault This class is used to parse a record as a HeadNode object.
 */
public class RecordParseDefault extends RecordParse {
    /**The log of the class.*/
    private static final Log LOG = LogFactory.getLog(RecordParseDefault.class);
    /**The vertex to be Parse.*/
    private Class<? extends Vertex<?, ?, ?>> vertexClass;

    /**
     * @param key The key of the vertex
     * @param value The value of the vertex
     * @return The vertex of the key and value
     */
    @Override
    public Vertex recordParse(String key, String value) {
        Vertex vertex = null;
        try {
            vertex = vertexClass.newInstance();
            vertex.fromString(key + Constants.KV_SPLIT_FLAG + value);
        } catch (Exception e) {
            LOG.error("RecordParse", e);
            return null;
        }
        return vertex;
    }

    /**
     * This method is used to parse a record and obtain VertexID .
     * @param key The key of the vertex record
     * @return the vertex id
     */
    @Override
    public Text getVertexID(Text key) {
        try {
            StringTokenizer str = new StringTokenizer(key.toString(), Constants.SPLIT_FLAG);
            if (str.countTokens() != 2) {
                return null;
            }
            return new Text(str.nextToken());
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * This method is used to initialize the RecordParseDefault.
     * @param job The Bsp job.
     */
    @Override
    public void init(BSPJob job) {
        this.vertexClass = job.getVertexClass();
    }
}