/**
* 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.*;
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.Mapper;
import org.apache.hadoop.mapred.OutputFormat;
import org.apache.hadoop.mrunit.internal.counters.CounterWrapper;
import org.apache.hadoop.mrunit.internal.mapred.MockReporter;
import org.apache.hadoop.mrunit.internal.output.MockOutputCreator;
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 Mapper instance. You provide the input
* (k, v)* pairs that should be sent to the Mapper, and outputs you expect to be
* sent by the Mapper to the collector for those inputs. By calling runTest(),
* the harness will deliver the input to the Mapper and will check its outputs
* against the expected results.
*/
public class MapDriver<K1, V1, K2, V2> extends MapDriverBase<K1, V1, K2, V2, MapDriver<K1, V1, K2, V2>> {
public static final Log LOG = LogFactory.getLog(MapDriver.class);
private Mapper<K1, V1, K2, V2> myMapper;
private Counters counters;
private final MockOutputCreator<K2, V2> mockOutputCreator = new MockOutputCreator<K2, V2>();
public MapDriver(final Mapper<K1, V1, K2, V2> m) {
this();
setMapper(m);
}
public MapDriver() {
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(counters);
}
/** Sets the counters to use and returns self for fluent style */
public MapDriver<K1, V1, K2, V2> withCounters(final Counters ctrs) {
setCounters(ctrs);
return this;
}
/**
* Set the Mapper instance to use with this test driver
*
* @param m
* the Mapper instance to use
*/
public void setMapper(final Mapper<K1, V1, K2, V2> m) {
myMapper = returnNonNull(m);
}
/** Sets the Mapper instance to use and returns self for fluent style */
public MapDriver<K1, V1, K2, V2> withMapper(final Mapper<K1, V1, K2, V2> m) {
setMapper(m);
return this;
}
/**
* @return the Mapper object being used by this test
*/
public Mapper<K1, V1, K2, V2> getMapper() {
return myMapper;
}
/**
* Configure {@link Mapper} 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 MapDriver<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(myMapper);
initDistributedCache();
final OutputCollectable<K2, V2> outputCollectable = mockOutputCreator
.createMapredOutputCollectable(getConfiguration(),
getOutputSerializationConfiguration());
final MockReporter reporter = new MockReporter(
MockReporter.ReporterType.Mapper, getCounters(),
getMapInputPath());
ReflectionUtils.setConf(myMapper, new JobConf(getConfiguration()));
for (Pair<K1, V1> kv : inputs) {
myMapper.map(kv.getFirst(), kv.getSecond(), outputCollectable, reporter);
}
myMapper.close();
return outputCollectable.getOutputs();
} finally {
cleanupDistributedCache();
}
}
@Override
public String toString() {
return "MapDriver (" + myMapper + ")";
}
/**
* Returns a new MapDriver without having to specify the generic types on the
* right hand side of the object create statement.
*
* @return new MapDriver
*/
public static <K1, V1, K2, V2> MapDriver<K1, V1, K2, V2> newMapDriver() {
return new MapDriver<K1, V1, K2, V2>();
}
/**
* Returns a new MapDriver without having to specify the generic types on the
* right hand side of the object create statement.
*
* @param mapper
* @return new MapDriver
*/
public static <K1, V1, K2, V2> MapDriver<K1, V1, K2, V2> newMapDriver(
final Mapper<K1, V1, K2, V2> mapper) {
return new MapDriver<K1, V1, K2, V2>(mapper);
}
}