| /* |
| * 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.crunch; |
| |
| import static org.junit.Assert.assertEquals; |
| import static org.junit.Assert.assertTrue; |
| |
| import org.apache.crunch.impl.mem.MemPipeline; |
| import org.apache.crunch.impl.mr.MRPipeline; |
| import org.apache.crunch.io.From; |
| import org.apache.crunch.test.TemporaryPath; |
| import org.apache.crunch.test.TemporaryPaths; |
| import org.apache.crunch.types.avro.Avros; |
| import org.junit.Before; |
| import org.junit.Rule; |
| import org.junit.Test; |
| |
| import com.google.common.collect.ImmutableMultiset; |
| import com.google.common.collect.Multiset; |
| |
| /** |
| * Tests for two phase (combine and reduce) CombineFns. |
| */ |
| public class CombineReduceIT { |
| |
| @Rule |
| public TemporaryPath tmpDir = TemporaryPaths.create(); |
| private String docsPath; |
| |
| @Before |
| public void setUp() throws Exception { |
| docsPath = tmpDir.copyResourceFileName("docs.txt"); |
| } |
| |
| static class CountCombiner extends CombineFn<String,Long> { |
| |
| private final int stringLengthLimit; |
| |
| public CountCombiner(int stringLengthLimit) { |
| this.stringLengthLimit = stringLengthLimit; |
| } |
| |
| @Override |
| public void process(Pair<String, Iterable<Long>> input, Emitter<Pair<String, Long>> emitter) { |
| String key = input.first(); |
| if (key.length() <= stringLengthLimit) { |
| long sum = 0L; |
| for (Long countValue : input.second()) { |
| sum += countValue; |
| } |
| emitter.emit(Pair.of(key, sum)); |
| } else { |
| for (Long countValue : input.second()) { |
| emitter.emit(Pair.of(key, countValue)); |
| } |
| } |
| } |
| |
| } |
| |
| @Test |
| public void testCombineValues_NoCombineOrReduceOfLongWords() throws Exception { |
| Iterable<Pair<String, Long>> mrResult = run( |
| new MRPipeline(CombineReduceIT.class, tmpDir.getDefaultConfiguration()), |
| docsPath, false, false); |
| Iterable<Pair<String, Long>> memResult = run( |
| MemPipeline.getInstance(), docsPath, false, false); |
| Multiset<Pair<String, Long>> mrResultSet = ImmutableMultiset.copyOf(mrResult); |
| Multiset<Pair<String, Long>> memResultSet = ImmutableMultiset.copyOf(memResult); |
| |
| assertEquals(mrResultSet, memResultSet); |
| |
| // Words with more than 3 characters shouldn't be combined at all |
| assertTrue(mrResultSet.contains(Pair.of("this", 1L))); |
| assertEquals(5, mrResultSet.count(Pair.of("this", 1L))); |
| } |
| |
| @Test |
| public void testCombineValues_OnlyReduceLongWords() throws Exception { |
| Iterable<Pair<String, Long>> mrResult = run( |
| new MRPipeline(CombineReduceIT.class, tmpDir.getDefaultConfiguration()), |
| docsPath, false, true); |
| Iterable<Pair<String, Long>> memResult = run( |
| MemPipeline.getInstance(), docsPath, false, true); |
| |
| Multiset<Pair<String, Long>> mrResultSet = ImmutableMultiset.copyOf(mrResult); |
| Multiset<Pair<String, Long>> memResultSet = ImmutableMultiset.copyOf(memResult); |
| |
| assertEquals(mrResultSet, memResultSet); |
| |
| // All words should be combined, although longer words will only |
| // have been combined in the reduce phase |
| assertTrue(mrResultSet.contains(Pair.of("this", 5L))); |
| assertEquals(1, mrResultSet.count(Pair.of("this", 5L))); |
| } |
| |
| @Test |
| public void testCombineValues_CombineAndReduceLongWords() throws Exception { |
| Iterable<Pair<String, Long>> mrResult = run( |
| new MRPipeline(CombineReduceIT.class, tmpDir.getDefaultConfiguration()), |
| docsPath, true, true); |
| Iterable<Pair<String, Long>> memResult = run( |
| MemPipeline.getInstance(), docsPath, true, true); |
| |
| Multiset<Pair<String, Long>> mrResultSet = ImmutableMultiset.copyOf(mrResult); |
| Multiset<Pair<String, Long>> memResultSet = ImmutableMultiset.copyOf(memResult); |
| |
| assertEquals(mrResultSet, memResultSet); |
| |
| // All words should be combined, both in the combiner and reducer |
| assertTrue(mrResultSet.contains(Pair.of("this", 5L))); |
| assertEquals(1, mrResultSet.count(Pair.of("this", 5L))); |
| } |
| |
| public static Iterable<Pair<String, Long>> run(Pipeline p, String inputPath, boolean combineLongWords, boolean reduceLongWords) |
| throws Exception { |
| return p.read(From.textFile(inputPath)) |
| .parallelDo("split", new DoFn<String, Pair<String, Long>>() { |
| @Override |
| public void process(String input, Emitter<Pair<String, Long>> emitter) { |
| for (String word : input.split("\\s+")) { |
| emitter.emit(Pair.of(word, 1L)); |
| } |
| } |
| }, Avros.tableOf(Avros.strings(), Avros.longs())) |
| .groupByKey() |
| .combineValues( |
| new CountCombiner(combineLongWords ? Integer.MAX_VALUE : 3), |
| new CountCombiner(reduceLongWords ? Integer.MAX_VALUE : 3)) |
| .materialize(); |
| } |
| } |