001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.hadoop.mapreduce.lib.db;
020
021import java.io.DataInput;
022import java.io.DataOutput;
023import java.io.IOException;
024import java.sql.Connection;
025import java.sql.DatabaseMetaData;
026import java.sql.PreparedStatement;
027import java.sql.ResultSet;
028import java.sql.SQLException;
029import java.sql.Statement;
030import java.sql.Types;
031import java.util.ArrayList;
032import java.util.List;
033
034import org.apache.commons.logging.Log;
035import org.apache.commons.logging.LogFactory;
036
037import org.apache.hadoop.io.LongWritable;
038import org.apache.hadoop.io.Text;
039import org.apache.hadoop.io.Writable;
040import org.apache.hadoop.mapreduce.InputFormat;
041import org.apache.hadoop.mapreduce.InputSplit;
042import org.apache.hadoop.mapreduce.Job;
043import org.apache.hadoop.mapreduce.JobContext;
044import org.apache.hadoop.mapreduce.RecordReader;
045import org.apache.hadoop.mapreduce.TaskAttemptContext;
046import org.apache.hadoop.util.ReflectionUtils;
047import org.apache.hadoop.classification.InterfaceAudience;
048import org.apache.hadoop.classification.InterfaceStability;
049import org.apache.hadoop.conf.Configurable;
050import org.apache.hadoop.conf.Configuration;
051
052/**
053 * A InputFormat that reads input data from an SQL table in an Oracle db.
054 */
055@InterfaceAudience.Public
056@InterfaceStability.Evolving
057public class OracleDataDrivenDBInputFormat<T extends DBWritable>
058    extends DataDrivenDBInputFormat<T> implements Configurable {
059
060  /**
061   * @return the DBSplitter implementation to use to divide the table/query into InputSplits.
062   */
063  @Override
064  protected DBSplitter getSplitter(int sqlDataType) {
065    switch (sqlDataType) {
066    case Types.DATE:
067    case Types.TIME:
068    case Types.TIMESTAMP:
069      return new OracleDateSplitter();
070
071    default:
072      return super.getSplitter(sqlDataType);
073    }
074  }
075
076  @Override
077  protected RecordReader<LongWritable, T> createDBRecordReader(DBInputSplit split,
078      Configuration conf) throws IOException {
079
080    DBConfiguration dbConf = getDBConf();
081    @SuppressWarnings("unchecked")
082    Class<T> inputClass = (Class<T>) (dbConf.getInputClass());
083
084    try {
085      // Use Oracle-specific db reader
086      return new OracleDataDrivenDBRecordReader<T>(split, inputClass,
087          conf, createConnection(), dbConf, dbConf.getInputConditions(),
088          dbConf.getInputFieldNames(), dbConf.getInputTableName());
089    } catch (SQLException ex) {
090      throw new IOException(ex.getMessage());
091    }
092  }
093}