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/** * 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.mapreduce.lib.reduce; import java.io.IOException; import java.net.URI; import org.apache.hadoop.classification.InterfaceAudience; import org.apache.hadoop.classification.InterfaceStability; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.conf.Configuration.IntegerRanges; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.RawComparator; import org.apache.hadoop.mapreduce.Counter; import org.apache.hadoop.mapreduce.InputFormat; import org.apache.hadoop.mapreduce.JobID; import org.apache.hadoop.mapreduce.Mapper; import org.apache.hadoop.mapreduce.OutputCommitter; import org.apache.hadoop.mapreduce.OutputFormat; import org.apache.hadoop.mapreduce.Partitioner; import org.apache.hadoop.mapreduce.ReduceContext; import org.apache.hadoop.mapreduce.Reducer; import org.apache.hadoop.mapreduce.TaskAttemptID; import org.apache.hadoop.security.Credentials; /** * A {@link Reducer} which wraps a given one to allow for custom * {@link Reducer.Context} implementations. */ @InterfaceAudience.Public @InterfaceStability.Evolving public class WrappedReducer<KEYIN, VALUEIN, KEYOUT, VALUEOUT> extends Reducer<KEYIN, VALUEIN, KEYOUT, VALUEOUT> { /** * A a wrapped {@link Reducer.Context} for custom implementations. * @param reduceContext <code>ReduceContext</code> to be wrapped * @return a wrapped <code>Reducer.Context</code> for custom implementations */ public Reducer<KEYIN, VALUEIN, KEYOUT, VALUEOUT>.Context getReducerContext( ReduceContext<KEYIN, VALUEIN, KEYOUT, VALUEOUT> reduceContext) { return new Context(reduceContext); } @InterfaceStability.Evolving public class Context extends Reducer<KEYIN, VALUEIN, KEYOUT, VALUEOUT>.Context { protected ReduceContext<KEYIN, VALUEIN, KEYOUT, VALUEOUT> reduceContext; public Context(ReduceContext<KEYIN, VALUEIN, KEYOUT, VALUEOUT> reduceContext) { this.reduceContext = reduceContext; } @Override public KEYIN getCurrentKey() throws IOException, InterruptedException { return reduceContext.getCurrentKey(); } @Override public VALUEIN getCurrentValue() throws IOException, InterruptedException { return reduceContext.getCurrentValue(); } @Override public boolean nextKeyValue() throws IOException, InterruptedException { return reduceContext.nextKeyValue(); } @Override public Counter getCounter(Enum counterName) { return reduceContext.getCounter(counterName); } @Override public Counter getCounter(String groupName, String counterName) { return reduceContext.getCounter(groupName, counterName); } @Override public OutputCommitter getOutputCommitter() { return reduceContext.getOutputCommitter(); } @Override public void write(KEYOUT key, VALUEOUT value) throws IOException, InterruptedException { reduceContext.write(key, value); } @Override public String getStatus() { return reduceContext.getStatus(); } @Override public TaskAttemptID getTaskAttemptID() { return reduceContext.getTaskAttemptID(); } @Override public void setStatus(String msg) { reduceContext.setStatus(msg); } @Override public Path[] getArchiveClassPaths() { return reduceContext.getArchiveClassPaths(); } @Override public String[] getArchiveTimestamps() { return reduceContext.getArchiveTimestamps(); } @Override public URI[] getCacheArchives() throws IOException { return reduceContext.getCacheArchives(); } @Override public URI[] getCacheFiles() throws IOException { return reduceContext.getCacheFiles(); } @Override public Class<? extends Reducer<?, ?, ?, ?>> getCombinerClass() throws ClassNotFoundException { return reduceContext.getCombinerClass(); } @Override public Configuration getConfiguration() { return reduceContext.getConfiguration(); } @Override public Path[] getFileClassPaths() { return reduceContext.getFileClassPaths(); } @Override public String[] getFileTimestamps() { return reduceContext.getFileTimestamps(); } @Override public RawComparator<?> getCombinerKeyGroupingComparator() { return reduceContext.getCombinerKeyGroupingComparator(); } @Override public RawComparator<?> getGroupingComparator() { return reduceContext.getGroupingComparator(); } @Override public Class<? extends InputFormat<?, ?>> getInputFormatClass() throws ClassNotFoundException { return reduceContext.getInputFormatClass(); } @Override public String getJar() { return reduceContext.getJar(); } @Override public JobID getJobID() { return reduceContext.getJobID(); } @Override public String getJobName() { return reduceContext.getJobName(); } @Override public boolean getJobSetupCleanupNeeded() { return reduceContext.getJobSetupCleanupNeeded(); } @Override public boolean getTaskCleanupNeeded() { return reduceContext.getTaskCleanupNeeded(); } @Override public Path[] getLocalCacheArchives() throws IOException { return reduceContext.getLocalCacheArchives(); } @Override public Path[] getLocalCacheFiles() throws IOException { return reduceContext.getLocalCacheFiles(); } @Override public Class<?> getMapOutputKeyClass() { return reduceContext.getMapOutputKeyClass(); } @Override public Class<?> getMapOutputValueClass() { return reduceContext.getMapOutputValueClass(); } @Override public Class<? extends Mapper<?, ?, ?, ?>> getMapperClass() throws ClassNotFoundException { return reduceContext.getMapperClass(); } @Override public int getMaxMapAttempts() { return reduceContext.getMaxMapAttempts(); } @Override public int getMaxReduceAttempts() { return reduceContext.getMaxReduceAttempts(); } @Override public int getNumReduceTasks() { return reduceContext.getNumReduceTasks(); } @Override public Class<? extends OutputFormat<?, ?>> getOutputFormatClass() throws ClassNotFoundException { return reduceContext.getOutputFormatClass(); } @Override public Class<?> getOutputKeyClass() { return reduceContext.getOutputKeyClass(); } @Override public Class<?> getOutputValueClass() { return reduceContext.getOutputValueClass(); } @Override public Class<? extends Partitioner<?, ?>> getPartitionerClass() throws ClassNotFoundException { return reduceContext.getPartitionerClass(); } @Override public Class<? extends Reducer<?, ?, ?, ?>> getReducerClass() throws ClassNotFoundException { return reduceContext.getReducerClass(); } @Override public RawComparator<?> getSortComparator() { return reduceContext.getSortComparator(); } @Override public boolean getSymlink() { return reduceContext.getSymlink(); } @Override public Path getWorkingDirectory() throws IOException { return reduceContext.getWorkingDirectory(); } @Override public void progress() { reduceContext.progress(); } @Override public Iterable<VALUEIN> getValues() throws IOException, InterruptedException { return reduceContext.getValues(); } @Override public boolean nextKey() throws IOException, InterruptedException { return reduceContext.nextKey(); } @Override public boolean getProfileEnabled() { return reduceContext.getProfileEnabled(); } @Override public String getProfileParams() { return reduceContext.getProfileParams(); } @Override public IntegerRanges getProfileTaskRange(boolean isMap) { return reduceContext.getProfileTaskRange(isMap); } @Override public String getUser() { return reduceContext.getUser(); } @Override public Credentials getCredentials() { return reduceContext.getCredentials(); } @Override public float getProgress() { return reduceContext.getProgress(); } } }