/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* Licensed 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 eu.stratosphere.nephele.jobmanager;
import eu.stratosphere.core.io.StringRecord;
import eu.stratosphere.runtime.io.api.MutableRecordReader;
import eu.stratosphere.runtime.io.api.RecordWriter;
import eu.stratosphere.runtime.io.api.UnionRecordReader;
import eu.stratosphere.nephele.template.AbstractTask;
/**
* A simple implementation of a task using a {@link UnionRecordReader}.
*/
public class UnionTask extends AbstractTask {
/**
* The union record reader to be used during the tests.
*/
private UnionRecordReader<StringRecord> unionReader;
private RecordWriter<StringRecord> writer;
@Override
public void registerInputOutput() {
@SuppressWarnings("unchecked")
MutableRecordReader<StringRecord>[] recordReaders = (MutableRecordReader<StringRecord>[]) new MutableRecordReader<?>[2];
recordReaders[0] = new MutableRecordReader<StringRecord>(this);
recordReaders[1] = new MutableRecordReader<StringRecord>(this);
this.unionReader = new UnionRecordReader<StringRecord>(recordReaders, StringRecord.class);
this.writer = new RecordWriter<StringRecord>(this);
}
@Override
public void invoke() throws Exception {
this.writer.initializeSerializers();
while (this.unionReader.hasNext()) {
this.writer.emit(this.unionReader.next());
}
this.writer.flush();
}
}