| /* |
| * 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.pirk.responder.wideskies.mapreduce; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.io.Text; |
| import org.apache.hadoop.mapreduce.Reducer; |
| import org.apache.hadoop.mapreduce.lib.output.MultipleOutputs; |
| import org.apache.pirk.utils.FileConst; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Reducer class to complete the exp lookup table and add to the Query object |
| * |
| */ |
| public class ExpTableReducer extends Reducer<Text,Text,Text,Text> |
| { |
| private static final Logger logger = LoggerFactory.getLogger(ExpTableReducer.class); |
| |
| private MultipleOutputs<Text,Text> mos = null; |
| private String reducerID = null; |
| |
| @Override |
| public void setup(Context ctx) throws IOException, InterruptedException |
| { |
| super.setup(ctx); |
| mos = new MultipleOutputs<>(ctx); |
| reducerID = String.format("%05d", ctx.getTaskAttemptID().getTaskID().getId()); |
| logger.info("reducerID = " + reducerID); |
| } |
| |
| @Override |
| public void reduce(Text key, Iterable<Text> vals, Context ctx) throws IOException, InterruptedException |
| { |
| logger.debug("Processing reducer for key = " + key.toString()); |
| |
| for (Text val : vals) // val: <power>-<element^power mod N^2> |
| { |
| mos.write(FileConst.EXP, key, val); |
| } |
| mos.write(FileConst.PIR, key, reducerID); |
| } |
| |
| @Override |
| public void cleanup(Context ctx) throws IOException, InterruptedException |
| { |
| mos.close(); |
| } |
| } |