/**
* 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.mahout.fpm.pfpgrowth.convertors;
import java.io.IOException;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapreduce.Reducer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* An output collector for {@link Reducer} for PFPGrowth which updates the status as well as writes the
* patterns generated by the algorithm
*
* @param <IK>
* @param <IV>
* @param <K>
* @param <V>
*/
public class ContextWriteOutputCollector<IK extends Writable,IV extends Writable,K extends Writable,V extends Writable>
implements OutputCollector<K,V> {
private static final Logger log = LoggerFactory.getLogger(ContextWriteOutputCollector.class);
private final Reducer<IK,IV,K,V>.Context context;
public ContextWriteOutputCollector(Reducer<IK,IV,K,V>.Context context) {
this.context = context;
}
@Override
public final void collect(K key, V value) throws IOException {
try {
context.setStatus("Writing Top K patterns for: " + key);
context.write(key, value);
} catch (InterruptedException e) {
log.error("{}", e);
}
}
}