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    
019    package org.apache.hadoop.mapreduce.lib.db;
020    
021    import java.io.DataInput;
022    import java.io.DataOutput;
023    import java.io.IOException;
024    import java.sql.Connection;
025    import java.sql.DatabaseMetaData;
026    import java.sql.PreparedStatement;
027    import java.sql.ResultSet;
028    import java.sql.SQLException;
029    import java.sql.Statement;
030    import java.sql.Types;
031    import java.util.ArrayList;
032    import java.util.List;
033    
034    import org.apache.commons.logging.Log;
035    import org.apache.commons.logging.LogFactory;
036    
037    import org.apache.hadoop.io.LongWritable;
038    import org.apache.hadoop.io.Text;
039    import org.apache.hadoop.io.Writable;
040    import org.apache.hadoop.mapreduce.InputFormat;
041    import org.apache.hadoop.mapreduce.InputSplit;
042    import org.apache.hadoop.mapreduce.Job;
043    import org.apache.hadoop.mapreduce.JobContext;
044    import org.apache.hadoop.mapreduce.RecordReader;
045    import org.apache.hadoop.mapreduce.TaskAttemptContext;
046    import org.apache.hadoop.util.ReflectionUtils;
047    import org.apache.hadoop.classification.InterfaceAudience;
048    import org.apache.hadoop.classification.InterfaceStability;
049    import org.apache.hadoop.conf.Configurable;
050    import 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
057    public 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, getConnection(), dbConf, dbConf.getInputConditions(),
088              dbConf.getInputFieldNames(), dbConf.getInputTableName());
089        } catch (SQLException ex) {
090          throw new IOException(ex.getMessage());
091        }
092      }
093    }