/***********************************************************************************************************************
* 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.test.iterative;
import java.io.Serializable;
import java.util.Iterator;
import eu.stratosphere.test.util.RecordAPITestBase;
import org.junit.Assert;
import eu.stratosphere.api.common.Plan;
import eu.stratosphere.api.java.record.operators.BulkIteration;
import eu.stratosphere.api.java.record.operators.FileDataSink;
import eu.stratosphere.api.java.record.operators.FileDataSource;
import eu.stratosphere.api.java.record.functions.MapFunction;
import eu.stratosphere.api.java.record.functions.ReduceFunction;
import eu.stratosphere.api.java.record.io.CsvOutputFormat;
import eu.stratosphere.api.java.record.io.TextInputFormat;
import eu.stratosphere.api.java.record.operators.MapOperator;
import eu.stratosphere.api.java.record.operators.ReduceOperator;
import eu.stratosphere.types.Record;
import eu.stratosphere.types.StringValue;
import eu.stratosphere.util.Collector;
public class IterationTerminationWithTwoTails extends RecordAPITestBase {
private static final String INPUT = "1\n" + "2\n" + "3\n" + "4\n" + "5\n";
private static final String EXPECTED = "22\n";
protected String dataPath;
protected String resultPath;
@Override
protected void preSubmit() throws Exception {
dataPath = createTempFile("datapoints.txt", INPUT);
resultPath = getTempFilePath("result");
}
@Override
protected void postSubmit() throws Exception {
compareResultsByLinesInMemory(EXPECTED, resultPath);
}
@Override
protected Plan getTestJob() {
return getTestPlanPlan(4, dataPath, resultPath);
}
private static Plan getTestPlanPlan(int numSubTasks, String input, String output) {
FileDataSource initialInput = new FileDataSource(TextInputFormat.class, input, "input");
BulkIteration iteration = new BulkIteration("Loop");
iteration.setInput(initialInput);
iteration.setMaximumNumberOfIterations(5);
Assert.assertTrue(iteration.getMaximumNumberOfIterations() > 1);
ReduceOperator sumReduce = ReduceOperator.builder(new SumReducer())
.input(iteration.getPartialSolution())
.name("Compute sum (Reduce)")
.build();
iteration.setNextPartialSolution(sumReduce);
MapOperator terminationMapper = MapOperator.builder(new TerminationMapper())
.input(iteration.getPartialSolution())
.name("Compute termination criterion (Map)")
.build();
iteration.setTerminationCriterion(terminationMapper);
FileDataSink finalResult = new FileDataSink(CsvOutputFormat.class, output, iteration, "Output");
CsvOutputFormat.configureRecordFormat(finalResult)
.recordDelimiter('\n')
.fieldDelimiter(' ')
.field(StringValue.class, 0);
Plan plan = new Plan(finalResult, "Iteration with AllReducer (keyless Reducer)");
plan.setDefaultParallelism(4);
Assert.assertTrue(plan.getDefaultParallelism() > 1);
return plan;
}
static final class SumReducer extends ReduceFunction implements Serializable {
private static final long serialVersionUID = 1L;
@Override
public void reduce(Iterator<Record> it, Collector<Record> out) {
// Compute the sum
int sum = 0;
while (it.hasNext()) {
sum += Integer.parseInt(it.next().getField(0, StringValue.class).getValue()) + 1;
}
out.collect(new Record(new StringValue(Integer.toString(sum))));
}
}
public static class TerminationMapper extends MapFunction implements Serializable {
private static final long serialVersionUID = 1L;
@Override
public void map(Record record, Collector<Record> collector) {
int currentSum = Integer.parseInt(record.getField(0, StringValue.class).getValue());
if(currentSum < 21)
collector.collect(record);
}
}
}