com.chinamobile.bcbsp.io.db.TableInputFormat.java Source code

Introduction

Here is the source code for com.chinamobile.bcbsp.io.db.TableInputFormat.java

Source

/**
 * 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.db;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.util.StringUtils;

/**
 * Convert HBase tabular data into a format that is consumable by BCBSP job.
 */
public class TableInputFormat extends TableInputFormatBase {
    /** Job parameter that specifies the input table. */
    public static final String INPUT_TABLE = "hbase.mapreduce.inputtable";

    /** Column Family to Scan */
    public static final String SCAN_COLUMN_FAMILY = "hbase.mapreduce.scan.column.family.input";

    /** Space delimited list of columns to scan. */
    public static final String SCAN_COLUMNS = "hbase.mapreduce.scan.columns.input";

    /** The timestamp used to filter columns with a specific timestamp. */
    public static final String SCAN_TIMESTAMP = "hbase.mapreduce.scan.timestamp";
    /**
     * The starting timestamp used to filter columns with a specific range of
     * versions.
     */
    public static final String SCAN_TIMERANGE_START = "hbase.mapreduce.scan.timerange.start";

    /**
     * The ending timestamp used to filter columns with a specific range of
     * versions.
     */
    public static final String SCAN_TIMERANGE_END = "hbase.mapreduce.scan.timerange.end";

    /** The maximum number of version to return. */
    public static final String SCAN_MAXVERSIONS = "hbase.mapreduce.scan.maxversions";

    /** Set to false to disable server-side caching of blocks for this scan. */
    public static final String SCAN_CACHEBLOCKS = "hbase.mapreduce.scan.cacheblocks";

    /** The number of rows for caching that will be passed to scanners. */
    public static final String SCAN_CACHEDROWS = "hbase.mapreduce.scan.cachedrows";

    /** Define LOG for outputting log information */
    private static final Log LOG = LogFactory.getLog(TableInputFormat.class);

    // Changed by Zhicheng Liu
    // 2013.4.17
    // Reason:"Scan.addColumns()" do not suit the new version of HBase API
    @Override
    public void initialize(Configuration configuration) {
        this.conf = HBaseConfiguration.create(configuration);
        this.conf.set("hbase.master", configuration.get("hbase.master"));
        this.conf.set("hbase.zookeeper.quorum", configuration.get("hbase.zookeeper.quorum"));
        //this.conf.set(INPUT_TABLE, configuration.get(INPUT_TABLE));
        this.conf.set(SCAN_COLUMN_FAMILY, configuration.get(SCAN_COLUMN_FAMILY));
        String tableName = conf.get(INPUT_TABLE);
        try {
            setTable(new HTable(conf, tableName));
        } catch (Exception e) {
            LOG.error(StringUtils.stringifyException(e));
        }
        Scan scan = null;
        try {
            scan = new Scan();
            if (conf.get(SCAN_COLUMNS) != null) {
                //scan.addColumns(conf.get(SCAN_COLUMNS));    
                scan.addColumn(Bytes.toBytes(conf.get(SCAN_COLUMN_FAMILY)), Bytes.toBytes(conf.get(SCAN_COLUMNS)));
            }
            if (conf.get(SCAN_COLUMN_FAMILY) != null) {
                scan.addFamily(Bytes.toBytes(conf.get(SCAN_COLUMN_FAMILY)));
            }
            if (conf.get(SCAN_TIMESTAMP) != null) {
                scan.setTimeStamp(Long.parseLong(conf.get(SCAN_TIMESTAMP)));
            }
            if (conf.get(SCAN_TIMERANGE_START) != null && conf.get(SCAN_TIMERANGE_END) != null) {
                scan.setTimeRange(Long.parseLong(conf.get(SCAN_TIMERANGE_START)),
                        Long.parseLong(conf.get(SCAN_TIMERANGE_END)));
            }
            if (conf.get(SCAN_MAXVERSIONS) != null) {
                scan.setMaxVersions(Integer.parseInt(conf.get(SCAN_MAXVERSIONS)));
            }
            if (conf.get(SCAN_CACHEDROWS) != null) {
                scan.setCaching(Integer.parseInt(conf.get(SCAN_CACHEDROWS)));
            }
            // false by default, full table scans generate too much BC churn
            scan.setCacheBlocks((conf.getBoolean(SCAN_CACHEBLOCKS, false)));
        } catch (Exception e) {
            LOG.error(StringUtils.stringifyException(e));
        }
        setScan(scan);
    }
}