/**
w * 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;
import java.io.IOException;
import java.util.regex.Pattern;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.mahout.common.Parameters;
/**
*
* maps all items in a particular transaction like the way it is done in Hadoop
* WordCount example
*
*/
public class ParallelCountingMapper extends Mapper<LongWritable,Text,Text,LongWritable> {
private static final LongWritable ONE = new LongWritable(1);
private Pattern splitter;
@Override
protected void map(LongWritable offset, Text input, Context context) throws IOException,
InterruptedException {
String[] items = splitter.split(input.toString());
for (String item : items) {
if (item.trim().isEmpty()) {
continue;
}
context.setStatus("Parallel Counting Mapper: " + item);
context.write(new Text(item), ONE);
}
}
@Override
protected void setup(Context context) throws IOException, InterruptedException {
super.setup(context);
Parameters params = new Parameters(context.getConfiguration().get(PFPGrowth.PFP_PARAMETERS, ""));
splitter = Pattern.compile(params.get(PFPGrowth.SPLIT_PATTERN, PFPGrowth.SPLITTER.toString()));
}
}