/** * 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 org.apache.hadoop.io.LongWritable; import org.apache.hadoop.mapreduce.Reducer; /** * takes each group of transactions and runs Vanilla FPGrowth on it and * outputs the the Top K frequent Patterns for each group. * */ public class TransactionSortingReducer extends Reducer<LongWritable,TransactionTree,LongWritable,TransactionTree> { private static final LongWritable ONE = new LongWritable(1); @Override protected void reduce(LongWritable key, Iterable<TransactionTree> values, Context context) throws IOException, InterruptedException { for (TransactionTree tr : values) { context.write(ONE, tr); } } }