oracle.kv.hadoop.table.TableInputFormat Maven / Gradle / Ivy
/*-
* Copyright (C) 2011, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This file was distributed by Oracle as part of a version of Oracle NoSQL
* Database made available at:
*
* http://www.oracle.com/technetwork/database/database-technologies/nosqldb/downloads/index.html
*
* Please see the LICENSE file included in the top-level directory of the
* appropriate version of Oracle NoSQL Database for a copy of the license and
* additional information.
*/
package oracle.kv.hadoop.table;
import java.io.IOException;
import oracle.kv.table.PrimaryKey;
import oracle.kv.table.Row;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
/**
* A Hadoop InputFormat class for reading data from an Oracle NoSQL Database.
* Map/reduce keys and values are returned as PrimaryKey and Row objects
* respectively.
*
* For information on the parameters that may be passed to this class,
* refer to the javadoc for the parent class of this class;
* TableInputFormatBase.
*
* A simple example demonstrating the Oracle NoSQL DB Hadoop
* oracle.kv.hadoop.table.TableInputFormat class can be found in the
* KVHOME/example/table/hadoop directory. It demonstrates how, in a MapReduce
* job, to read records from an Oracle NoSQL Database that were written using
* Table API. The javadoc for that program describes the simple Map/Reduce
* processing as well as how to invoke the program in Hadoop.
*
* @since 3.1
*/
public class TableInputFormat extends TableInputFormatBase {
/**
* Returns the RecordReader for the given InputSplit.
*/
@Override
public RecordReader
createRecordReader(InputSplit split, TaskAttemptContext context)
throws IOException, InterruptedException {
final TableRecordReader ret = new TableRecordReader();
ret.initialize(split, context);
return ret;
}
}