| /** |
| * 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.apex.malhar.contrib.misc.algo; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.apex.malhar.lib.util.BaseKeyValueOperator; |
| |
| import com.datatorrent.api.DefaultInputPort; |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.api.annotation.OperatorAnnotation; |
| |
| /** |
| * This operator takes a stream of key value pairs each window, |
| * and outputs a set of inverted key value pairs at the end of each window. |
| * The values in the key value pairs received by this operator are an array lists, which may multiple values. |
| * <p> |
| * Inverts the index and sends out the tuple on output port "index" at the end of the window. |
| * </p> |
| * <p> |
| * This is an end of window operator<br> |
| * <br> |
| * <b>StateFull : Yes, </b> tuple are compare across application window(s). <br> |
| * <b>Partitions : Yes, </b> inverted indexes are unified by instance of same operator. <br> |
| * <br> |
| * <b>Ports</b>:<br> |
| * <b>data</b>: expects HashMap<K,ArrayList<V>><br> |
| * <b>index</b>: emits HashMap<V,ArrayList<K>>(1), one HashMap per V<br> |
| * <br> |
| * </p> |
| * |
| * @displayName Invert Key Value Pairs (Array) |
| * @category Stream Manipulators |
| * @tags key value |
| * |
| * @since 0.3.2 |
| * @deprecated |
| */ |
| @Deprecated |
| @OperatorAnnotation(partitionable = true) |
| public class InvertIndexArray<K, V> extends BaseKeyValueOperator<K,V> |
| { |
| /** |
| * Inverted key/value map. |
| */ |
| protected HashMap<V, ArrayList<K>> map = new HashMap<V, ArrayList<K>>(); |
| |
| /** |
| * The input port on which key value pairs are received. |
| */ |
| public final transient DefaultInputPort<HashMap<K, ArrayList<V>>> data = new DefaultInputPort<HashMap<K, ArrayList<V>>>() |
| { |
| /** |
| * Reverse indexes a HashMap<K, ArrayList<V>> tuple |
| */ |
| @Override |
| public void process(HashMap<K, ArrayList<V>> tuple) |
| { |
| for (Map.Entry<K, ArrayList<V>> e: tuple.entrySet()) { |
| ArrayList<V> alist = e.getValue(); |
| if (alist == null) { // error tuple? |
| continue; |
| } |
| for (V val : alist) { |
| insert(val, cloneKey(e.getKey())); |
| } |
| } |
| } |
| }; |
| |
| /** |
| * The output port or which inverted key value pairs are emitted. |
| */ |
| public final transient DefaultOutputPort<HashMap<V, ArrayList<K>>> index = new DefaultOutputPort<HashMap<V, ArrayList<K>>>() |
| { |
| @Override |
| public Unifier<HashMap<V, ArrayList<K>>> getUnifier() |
| { |
| return new InvertIndex<K, V>(); |
| } |
| }; |
| |
| /** |
| * |
| * Returns the ArrayList stored for a key |
| * |
| * @param key |
| */ |
| void insert(V val, K key) |
| { |
| ArrayList<K> list = map.get(val); |
| if (list == null) { |
| list = new ArrayList<K>(4); |
| map.put(cloneValue(val), list); |
| } |
| list.add(key); |
| } |
| |
| /** |
| * Emit all the data and clear the hash |
| */ |
| @Override |
| public void endWindow() |
| { |
| for (Map.Entry<V, ArrayList<K>> e: map.entrySet()) { |
| HashMap<V, ArrayList<K>> tuple = new HashMap<V, ArrayList<K>>(1); |
| tuple.put(e.getKey(), e.getValue()); |
| index.emit(tuple); |
| } |
| map.clear(); |
| } |
| } |