/*
* 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 org.apache.jena.hadoop.rdf.io.input.readers;
import java.io.IOException;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.jena.graph.Node ;
import org.apache.jena.hadoop.rdf.types.QuadWritable;
import org.apache.jena.hadoop.rdf.types.TripleWritable;
import org.apache.jena.sparql.core.Quad ;
/**
* A record reader that converts triples into quads by wrapping a
* {@code RecordReader<LongWritable, TripleWritable>} implementation
*
*
*
*/
public class TriplesToQuadsReader extends RecordReader<LongWritable, QuadWritable> {
private final RecordReader<LongWritable, TripleWritable> reader;
private Node graph;
/**
* Creates a new reader
*
* @param reader
* Triple reader
*/
public TriplesToQuadsReader(RecordReader<LongWritable, TripleWritable> reader) {
this(reader, Quad.defaultGraphNodeGenerated);
}
/**
* Creates a new reader
*
* @param reader
* Triple reader
* @param graphNode
* Graph node
*/
public TriplesToQuadsReader(RecordReader<LongWritable, TripleWritable> reader, Node graphNode) {
if (reader == null)
throw new NullPointerException("reader cannot be null");
if (graphNode == null)
throw new NullPointerException("Graph node cannot be null");
this.reader = reader;
this.graph = graphNode;
}
@Override
public void initialize(InputSplit split, TaskAttemptContext context) throws IOException, InterruptedException {
this.reader.initialize(split, context);
}
@Override
public final boolean nextKeyValue() throws IOException, InterruptedException {
return this.reader.nextKeyValue();
}
@Override
public final LongWritable getCurrentKey() throws IOException, InterruptedException {
return this.reader.getCurrentKey();
}
@Override
public final QuadWritable getCurrentValue() throws IOException, InterruptedException {
TripleWritable t = this.reader.getCurrentValue();
return new QuadWritable(new Quad(this.graph, t.get()));
}
@Override
public final float getProgress() throws IOException, InterruptedException {
return this.reader.getProgress();
}
@Override
public final void close() throws IOException {
this.reader.close();
}
}