org.apache.jena.hadoop.rdf.io.output.writers

Class AbstractWholeFileNodeTupleWriter<TKey,TValue,T extends AbstractNodeTupleWritable<TValue>>

java.lang.Object

org.apache.hadoop.mapreduce.RecordWriter<TKey,T>

org.apache.jena.hadoop.rdf.io.output.writers.AbstractWholeFileNodeTupleWriter<TKey,TValue,T>

Type Parameters:

TKey -

TValue -

T -

Direct Known Subclasses:

AbstractWholeFileQuadWriter, AbstractWholeFileTripleWriter

public abstract class AbstractWholeFileNodeTupleWriter<TKey,TValue,T extends AbstractNodeTupleWritable<TValue>>
extends org.apache.hadoop.mapreduce.RecordWriter<TKey,T>

An abstract implementation of a record writer that writes records to whole file formats.

It is important to note that the writer does not actually write any output until the close(TaskAttemptContext) method is called as it must write the entire output in one go otherwise the output would be invalid. Also writing in one go increases the chances that the writer will be able to effectively use the syntax compressions of the RDF serialization being used.

The implementation only writes the value portion of the key value pair since it is the value portion that is used to convey the node tuples

Method Summary

Modifier and Type	Method and Description
void	close(org.apache.hadoop.mapreduce.TaskAttemptContext context)
void	write(TKey key, T value)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

write

public final void write(TKey key,
                        T value)

Specified by:

write in class org.apache.hadoop.mapreduce.RecordWriter<TKey,T extends AbstractNodeTupleWritable<TValue>>

close

public void close(org.apache.hadoop.mapreduce.TaskAttemptContext context)
           throws IOException

Specified by:

close in class org.apache.hadoop.mapreduce.RecordWriter<TKey,T extends AbstractNodeTupleWritable<TValue>>

Throws:

IOException