| /** |
| * 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.hadoop.mrunit; |
| |
| import static org.apache.hadoop.mrunit.internal.util.ArgumentChecker.returnNonNull; |
| |
| import java.io.IOException; |
| import java.util.List; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.mapred.Counters; |
| import org.apache.hadoop.mapred.InputFormat; |
| import org.apache.hadoop.mapred.JobConf; |
| import org.apache.hadoop.mapred.OutputFormat; |
| import org.apache.hadoop.mapred.Reducer; |
| import org.apache.hadoop.mrunit.internal.counters.CounterWrapper; |
| import org.apache.hadoop.mrunit.internal.mapred.MockReporter; |
| import org.apache.hadoop.mrunit.internal.output.OutputCollectable; |
| import org.apache.hadoop.mrunit.types.Pair; |
| import org.apache.hadoop.util.ReflectionUtils; |
| |
| /** |
| * Harness that allows you to test a Reducer instance. You provide a key and a |
| * set of intermediate values for that key that represent inputs that should be |
| * sent to the Reducer (as if they came from a Mapper), and outputs you expect |
| * to be sent by the Reducer to the collector. By calling runTest(), the harness |
| * will deliver the input to the Reducer and will check its outputs against the |
| * expected results. |
| */ |
| public class ReduceDriver<K1, V1, K2, V2> extends |
| ReduceDriverBase<K1, V1, K2, V2, ReduceDriver<K1, V1, K2, V2>> { |
| |
| public static final Log LOG = LogFactory.getLog(ReduceDriver.class); |
| |
| private Reducer<K1, V1, K2, V2> myReducer; |
| private Counters counters; |
| |
| public ReduceDriver(final Reducer<K1, V1, K2, V2> r) { |
| this(); |
| setReducer(r); |
| } |
| |
| public ReduceDriver() { |
| setCounters(new Counters()); |
| } |
| |
| /** @return the counters used in this test */ |
| public Counters getCounters() { |
| return counters; |
| } |
| |
| /** |
| * Sets the counters object to use for this test. |
| * |
| * @param ctrs |
| * The counters object to use. |
| */ |
| public void setCounters(final Counters ctrs) { |
| counters = ctrs; |
| counterWrapper = new CounterWrapper(ctrs); |
| } |
| |
| /** Sets the counters to use and returns self for fluent style */ |
| public ReduceDriver<K1, V1, K2, V2> withCounters(final Counters ctrs) { |
| setCounters(ctrs); |
| return this; |
| } |
| |
| /** |
| * Sets the reducer object to use for this test |
| * |
| * @param r |
| * The reducer object to use |
| */ |
| public void setReducer(final Reducer<K1, V1, K2, V2> r) { |
| myReducer = returnNonNull(r); |
| } |
| |
| /** |
| * Identical to setReducer(), but with fluent programming style |
| * |
| * @param r |
| * The Reducer to use |
| * @return this |
| */ |
| public ReduceDriver<K1, V1, K2, V2> withReducer( |
| final Reducer<K1, V1, K2, V2> r) { |
| setReducer(r); |
| return this; |
| } |
| |
| public Reducer<K1, V1, K2, V2> getReducer() { |
| return myReducer; |
| } |
| |
| /** |
| * Configure {@link Reducer} to output with a real {@link OutputFormat}. Set |
| * {@link InputFormat} to read output back in for use with run* methods |
| * |
| * @param outputFormatClass |
| * @param inputFormatClass |
| * @return this for fluent style |
| */ |
| @SuppressWarnings("rawtypes") |
| public ReduceDriver<K1, V1, K2, V2> withOutputFormat( |
| final Class<? extends OutputFormat> outputFormatClass, |
| final Class<? extends InputFormat> inputFormatClass) { |
| mockOutputCreator.setMapredFormats(outputFormatClass, inputFormatClass); |
| return this; |
| } |
| |
| @Override |
| public List<Pair<K2, V2>> run() throws IOException { |
| try { |
| preRunChecks(myReducer); |
| initDistributedCache(); |
| final OutputCollectable<K2, V2> outputCollectable = mockOutputCreator |
| .createMapredOutputCollectable(getConfiguration(), |
| getOutputSerializationConfiguration()); |
| final MockReporter reporter = new MockReporter( |
| MockReporter.ReporterType.Reducer, getCounters()); |
| |
| ReflectionUtils.setConf(myReducer, new JobConf(getConfiguration())); |
| |
| for (Pair<K1, List<V1>> kv : inputs) { |
| myReducer.reduce(kv.getFirst(), kv.getSecond().iterator(), |
| outputCollectable, reporter); |
| } |
| myReducer.close(); |
| return outputCollectable.getOutputs(); |
| } finally { |
| cleanupDistributedCache(); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return "ReduceDriver (" + myReducer + ")"; |
| } |
| |
| /** |
| * Returns a new ReduceDriver without having to specify the generic types on |
| * the right hand side of the object create statement. |
| * |
| * @return new ReduceDriver |
| */ |
| public static <K1, V1, K2, V2> ReduceDriver<K1, V1, K2, V2> newReduceDriver() { |
| return new ReduceDriver<K1, V1, K2, V2>(); |
| } |
| |
| /** |
| * Returns a new ReduceDriver without having to specify the generic types on |
| * the right hand side of the object create statement. |
| * |
| * |
| * @param reducer |
| * passed to ReduceDriver constructor |
| * @return new ReduceDriver |
| */ |
| public static <K1, V1, K2, V2> ReduceDriver<K1, V1, K2, V2> newReduceDriver( |
| final Reducer<K1, V1, K2, V2> reducer) { |
| return new ReduceDriver<K1, V1, K2, V2>(reducer); |
| } |
| } |