com.chinamobile.bcbsp.io.mysql.DBInputSplit.java Source code

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Here is the source code for com.chinamobile.bcbsp.io.mysql.DBInputSplit.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.io.mysql;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapreduce.InputSplit;

/**
 * A MySQL split corresponds to a key range (low, high). All references to row
 * below refer to the key of the row.
 */
public class DBInputSplit extends InputSplit implements Writable, Comparable<DBInputSplit> {
    /** The split end */
    private long end = 0;
    /** The split start */
    private long start = 0;
    /** the region location */
    private String regionLocation = null;

    /**
     * Default Constructor
     */
    public DBInputSplit() {
    }

    /**
     * Convenience Constructor
     *
     * @param start
     *        the index of the first row to select
     * @param end
     *        the index of the last row to select
     */
    public DBInputSplit(long start, long end) {
        this.start = start;
        this.end = end;
    }

    public String getRegionLocation() {
        return regionLocation;
    }

    /**
     * Returns the region's location as an array.
     *
     * @return The array containing the region location.
     */

    @Override
    public String[] getLocations() throws IOException {
        regionLocation = "";
        return new String[] { regionLocation };
    }

    /**
     * @return The index of the first row to select
     */
    public long getStart() {
        return start;
    }

    /**
     * @return The index of the last row to select
     */
    public long getEnd() {
        return end;
    }

    /**
     * @return The total row count in this split
     */
    @Override
    public long getLength() throws IOException {
        return end - start;
    }

    @Override
    public void readFields(DataInput input) throws IOException {
        start = input.readLong();
        end = input.readLong();
    }

    @Override
    public void write(DataOutput output) throws IOException {
        output.writeLong(start);
        output.writeLong(end);
    }

    @Override
    public int compareTo(DBInputSplit split) {
        // return long.compareTo(getStart(), split.getStart());
        return 0;
    }
}