Java tutorial
/*********************************************************************************************************************** * 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.pact.runtime.task; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import junit.framework.Assert; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.junit.Test; import eu.stratosphere.api.common.functions.GenericGroupReduce; import eu.stratosphere.api.java.record.functions.ReduceFunction; import eu.stratosphere.api.java.record.operators.ReduceOperator.Combinable; import eu.stratosphere.api.java.typeutils.runtime.record.RecordComparator; import eu.stratosphere.api.java.typeutils.runtime.record.RecordSerializerFactory; import eu.stratosphere.pact.runtime.sort.CombiningUnilateralSortMerger; import eu.stratosphere.pact.runtime.test.util.DriverTestBase; import eu.stratosphere.pact.runtime.test.util.UniformRecordGenerator; import eu.stratosphere.types.IntValue; import eu.stratosphere.types.Key; import eu.stratosphere.types.Record; import eu.stratosphere.util.Collector; public class ReduceTaskExternalITCase extends DriverTestBase<GenericGroupReduce<Record, Record>> { private static final Log LOG = LogFactory.getLog(ReduceTaskExternalITCase.class); @SuppressWarnings("unchecked") private final RecordComparator comparator = new RecordComparator(new int[] { 0 }, (Class<? extends Key<?>>[]) new Class[] { IntValue.class }); private final List<Record> outList = new ArrayList<Record>(); public ReduceTaskExternalITCase() { super(0, 1, 3 * 1024 * 1024); } @Test public void testSingleLevelMergeReduceTask() { final int keyCnt = 8192; final int valCnt = 8; setNumFileHandlesForSort(2); addInputComparator(this.comparator); setOutput(this.outList); getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE); try { addInputSorted(new UniformRecordGenerator(keyCnt, valCnt, false), this.comparator.duplicate()); GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>(); testDriver(testTask, MockReduceStub.class); } catch (Exception e) { LOG.debug(e); Assert.fail("Exception in Test."); } Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt, this.outList.size() == keyCnt); for (Record record : this.outList) { Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == valCnt - record.getField(0, IntValue.class).getValue()); } this.outList.clear(); } @Test public void testMultiLevelMergeReduceTask() { final int keyCnt = 32768; final int valCnt = 8; setNumFileHandlesForSort(2); addInputComparator(this.comparator); setOutput(this.outList); getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE); try { addInputSorted(new UniformRecordGenerator(keyCnt, valCnt, false), this.comparator.duplicate()); GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>(); testDriver(testTask, MockReduceStub.class); } catch (Exception e) { LOG.debug(e); Assert.fail("Exception in Test."); } Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt, this.outList.size() == keyCnt); for (Record record : this.outList) { Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == valCnt - record.getField(0, IntValue.class).getValue()); } this.outList.clear(); } @Test public void testSingleLevelMergeCombiningReduceTask() { final int keyCnt = 8192; final int valCnt = 8; addInputComparator(this.comparator); setOutput(this.outList); getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE); CombiningUnilateralSortMerger<Record> sorter = null; try { sorter = new CombiningUnilateralSortMerger<Record>(new MockCombiningReduceStub(), getMemoryManager(), getIOManager(), new UniformRecordGenerator(keyCnt, valCnt, false), getOwningNepheleTask(), RecordSerializerFactory.get(), this.comparator.duplicate(), this.perSortMem, 2, 0.8f); addInput(sorter.getIterator()); GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>(); testDriver(testTask, MockCombiningReduceStub.class); } catch (Exception e) { LOG.debug(e); Assert.fail("Invoke method caused exception."); } finally { if (sorter != null) { sorter.close(); } } int expSum = 0; for (int i = 1; i < valCnt; i++) { expSum += i; } Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt, this.outList.size() == keyCnt); for (Record record : this.outList) { Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == expSum - record.getField(0, IntValue.class).getValue()); } this.outList.clear(); } @Test public void testMultiLevelMergeCombiningReduceTask() { int keyCnt = 32768; int valCnt = 8; addInputComparator(this.comparator); setOutput(this.outList); getTaskConfig().setDriverStrategy(DriverStrategy.SORTED_GROUP_REDUCE); CombiningUnilateralSortMerger<Record> sorter = null; try { sorter = new CombiningUnilateralSortMerger<Record>(new MockCombiningReduceStub(), getMemoryManager(), getIOManager(), new UniformRecordGenerator(keyCnt, valCnt, false), getOwningNepheleTask(), RecordSerializerFactory.get(), this.comparator.duplicate(), this.perSortMem, 2, 0.8f); addInput(sorter.getIterator()); GroupReduceDriver<Record, Record> testTask = new GroupReduceDriver<Record, Record>(); testDriver(testTask, MockCombiningReduceStub.class); } catch (Exception e) { LOG.debug(e); Assert.fail("Invoke method caused exception."); } finally { if (sorter != null) { sorter.close(); } } int expSum = 0; for (int i = 1; i < valCnt; i++) { expSum += i; } Assert.assertTrue("Resultset size was " + this.outList.size() + ". Expected was " + keyCnt, this.outList.size() == keyCnt); for (Record record : this.outList) { Assert.assertTrue("Incorrect result", record.getField(1, IntValue.class).getValue() == expSum - record.getField(0, IntValue.class).getValue()); } this.outList.clear(); } public static class MockReduceStub extends ReduceFunction { private static final long serialVersionUID = 1L; private final IntValue key = new IntValue(); private final IntValue value = new IntValue(); @Override public void reduce(Iterator<Record> records, Collector<Record> out) throws Exception { Record element = null; int cnt = 0; while (records.hasNext()) { element = records.next(); cnt++; } element.getField(0, this.key); this.value.setValue(cnt - this.key.getValue()); element.setField(1, this.value); out.collect(element); } } @Combinable public static class MockCombiningReduceStub extends ReduceFunction { private static final long serialVersionUID = 1L; private final IntValue key = new IntValue(); private final IntValue value = new IntValue(); private final IntValue combineValue = new IntValue(); @Override public void reduce(Iterator<Record> records, Collector<Record> out) throws Exception { Record element = null; int sum = 0; while (records.hasNext()) { element = records.next(); element.getField(1, this.value); sum += this.value.getValue(); } element.getField(0, this.key); this.value.setValue(sum - this.key.getValue()); element.setField(1, this.value); out.collect(element); } @Override public void combine(Iterator<Record> records, Collector<Record> out) throws Exception { Record element = null; int sum = 0; while (records.hasNext()) { element = records.next(); element.getField(1, this.combineValue); sum += this.combineValue.getValue(); } this.combineValue.setValue(sum); element.setField(1, this.combineValue); out.collect(element); } } }