| /** |
| * 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.lib.math; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.apex.malhar.lib.util.BaseNumberKeyValueOperator; |
| import org.apache.apex.malhar.lib.util.KeyValPair; |
| import org.apache.commons.lang.mutable.MutableDouble; |
| import org.apache.commons.lang.mutable.MutableLong; |
| |
| import com.datatorrent.api.DefaultInputPort; |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.api.annotation.OutputPortFieldAnnotation; |
| |
| /** |
| * |
| * Emits the average of values for each key at the end of window. |
| * <p> |
| * <br>User can block or only enable certain keys by setting filter-keys/inverse operator properties. |
| * <br> Block Key : inverse=true |
| * <br> Enable Key : inverse=false |
| * This is an end window operator. This can not be partitioned. Partitioning |
| * this will yield incorrect result.<br> |
| * <br> |
| * <b>Ports</b>:<br> |
| * <b>data</b>: expects KeyValPair<K,V extends Number><br> |
| * <b>averagePort(s)</b>: emits KeyValPair<K,V extends Number></b><br> |
| * <br>Output ports are optional. |
| * <br> |
| * <b>Properties</b>:<br> |
| * <b>inverse</b>: if set to true the key in the filter will block tuple (default : true).<br> |
| * <b>filterBy</b>: List of keys to filter on.<br> |
| * <br> |
| * <b>Specific compile time checks</b>: None<br> |
| * <b>Specific run time checks</b>: None<br> |
| * <p> |
| * @displayName Average Key Value |
| * @category Math |
| * @tags average, number, end window, key value |
| * @since 0.3.3 |
| */ |
| public class AverageKeyVal<K> extends BaseNumberKeyValueOperator<K, Number> |
| { |
| // Aggregate sum of all values seen for a key. |
| protected HashMap<K, MutableDouble> sums = new HashMap<K, MutableDouble>(); |
| |
| // Count of number of values seen for key. |
| protected HashMap<K, MutableLong> counts = new HashMap<K, MutableLong>(); |
| |
| /** |
| * Input port that takes a key value pair. |
| */ |
| public final transient DefaultInputPort<KeyValPair<K, ? extends Number>> data = new DefaultInputPort<KeyValPair<K, ? extends Number>>() |
| { |
| /** |
| * Adds the values for each key, counts the number of occurrences of each |
| * key and computes the average. |
| */ |
| @Override |
| public void process(KeyValPair<K, ? extends Number> tuple) |
| { |
| K key = tuple.getKey(); |
| if (!doprocessKey(key)) { |
| return; |
| } |
| MutableDouble val = sums.get(key); |
| if (val == null) { |
| val = new MutableDouble(tuple.getValue().doubleValue()); |
| } else { |
| val.add(tuple.getValue().doubleValue()); |
| } |
| sums.put(cloneKey(key), val); |
| |
| MutableLong count = counts.get(key); |
| if (count == null) { |
| count = new MutableLong(0); |
| counts.put(cloneKey(key), count); |
| } |
| count.increment(); |
| } |
| }; |
| |
| /** |
| * Double average output port. |
| */ |
| @OutputPortFieldAnnotation(optional = true) |
| public final transient DefaultOutputPort<KeyValPair<K, Double>> doubleAverage = |
| new DefaultOutputPort<KeyValPair<K, Double>>(); |
| |
| /** |
| * Integer average output port. |
| */ |
| @OutputPortFieldAnnotation(optional = true) |
| public final transient DefaultOutputPort<KeyValPair<K, Integer>> intAverage = |
| new DefaultOutputPort<KeyValPair<K, Integer>>(); |
| |
| /** |
| * Long average output port. |
| */ |
| @OutputPortFieldAnnotation(optional = true) |
| public final transient DefaultOutputPort<KeyValPair<K, Long>> longAverage = |
| new DefaultOutputPort<KeyValPair<K, Long>>(); |
| |
| /** |
| * Emits average for each key in end window. Data is computed during process |
| * on input port Clears the internal data before return. |
| */ |
| @Override |
| public void endWindow() |
| { |
| for (Map.Entry<K, MutableDouble> e : sums.entrySet()) { |
| K key = e.getKey(); |
| double d = e.getValue().doubleValue(); |
| if (doubleAverage.isConnected()) { |
| doubleAverage.emit(new KeyValPair<K, Double>(key, d / counts.get(key).doubleValue())); |
| } |
| if (intAverage.isConnected()) { |
| intAverage.emit(new KeyValPair<K, Integer>(key, (int)d)); |
| } |
| if (longAverage.isConnected()) { |
| longAverage.emit(new KeyValPair<K, Long>(key, (long)d)); |
| } |
| } |
| sums.clear(); |
| counts.clear(); |
| } |
| } |