| /* |
| * 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.pig.impl.builtin; |
| |
| import java.io.IOException; |
| import java.util.Map; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.pig.EvalFunc; |
| import org.apache.pig.PigConstants; |
| import org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapReduce; |
| import org.apache.pig.backend.hadoop.executionengine.util.MapRedUtil; |
| import org.apache.pig.data.DataType; |
| import org.apache.pig.data.Tuple; |
| import org.apache.pig.data.TupleFactory; |
| import org.apache.pig.impl.util.Pair; |
| import org.apache.pig.impl.util.UDFContext; |
| |
| public class IsFirstReduceOfKey extends EvalFunc<Boolean> { |
| protected static final TupleFactory tf = TupleFactory.getInstance(); |
| protected Map<Object, Pair<Integer, Integer> > reducerMap = null; |
| /* Loads the key distribution file obtained from the sampler */ |
| protected void init() { |
| Configuration conf = PigMapReduce.sJobConfInternal.get(); |
| String keyDistFile = conf.get("pig.keyDistFile", ""); |
| if (keyDistFile.length() == 0) { |
| throw new RuntimeException(this.getClass().getSimpleName() + |
| " used but no key distribution found"); |
| } |
| |
| try { |
| Integer [] redCnt = new Integer[1]; |
| reducerMap = MapRedUtil.loadPartitionFileFromLocalCache( |
| keyDistFile, redCnt, DataType.TUPLE, conf); |
| } catch (Exception e) { |
| throw new RuntimeException(e); |
| } |
| } |
| |
| @Override |
| public Boolean exec(Tuple input) throws IOException { |
| if (reducerMap == null) { |
| init(); |
| } |
| Object key = input.get(0); |
| Tuple keyTuple = tf.newTuple(1); |
| keyTuple.set(0, key); |
| if (!reducerMap.containsKey(keyTuple)) { |
| return true; |
| } |
| int firstReducerOfKey = reducerMap.get(keyTuple).first; |
| int reduceIndex = UDFContext.getUDFContext().getJobConf().getInt(PigConstants.TASK_INDEX, 0); |
| if (firstReducerOfKey == reduceIndex) { |
| return true; |
| } |
| return false; |
| } |
| |
| } |