| package com.datatorrent.lib.util; |
| /* |
| * Copyright (c) 2013 DataTorrent, Inc. ALL Rights Reserved. |
| * |
| * Licensed 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. |
| */ |
| import java.util.ArrayList; |
| |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.api.Context.OperatorContext; |
| import com.datatorrent.api.Operator.Unifier; |
| |
| /** |
| * This unifier takes lists as input tuples. |
| * The unifier combines all the lists it receives within an application window and emits them at the end of the window. |
| * <p> |
| * The processing is done with sticky key partitioning, i.e. each one key belongs only to one partition. |
| * </p> |
| * @displayName Unifier Array List |
| * @category Algorithmic |
| * @tags unifier |
| * @since 0.3.3 |
| */ |
| public class UnifierArrayList<K> implements Unifier<ArrayList<K>> |
| { |
| // merged list |
| private ArrayList<K> mergedList; |
| |
| @Override |
| public void beginWindow(long arg0) |
| { |
| mergedList = new ArrayList<K>(); |
| } |
| |
| @Override |
| public void endWindow() |
| { |
| mergedport.emit(mergedList); |
| } |
| |
| @Override |
| public void setup(OperatorContext arg0) |
| { |
| // TODO Auto-generated method stub |
| |
| } |
| |
| @Override |
| public void teardown() |
| { |
| // TODO Auto-generated method stub |
| |
| } |
| |
| /** |
| * This is the output port that emits a merged list constructed from input lists. |
| */ |
| public final transient DefaultOutputPort<ArrayList<K>> mergedport = new DefaultOutputPort<ArrayList<K>>(); |
| |
| @Override |
| public void process(ArrayList<K> tuple) |
| { |
| for (int i = 0; i < tuple.size(); i++) { |
| mergedList.add(tuple.get(i)); |
| } |
| } |
| |
| } |