com.datatorrent.lib.math.MarginKeyVal.java Source code

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Here is the source code for com.datatorrent.lib.math.MarginKeyVal.java

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/**
 * 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 com.datatorrent.lib.math;

import java.util.HashMap;
import java.util.Map;

import org.apache.commons.lang.mutable.MutableDouble;

import com.datatorrent.api.DefaultInputPort;
import com.datatorrent.api.DefaultOutputPort;
import com.datatorrent.api.StreamCodec;
import com.datatorrent.lib.util.BaseNumberKeyValueOperator;
import com.datatorrent.lib.util.KeyValPair;

/**
 *
 * This operator adds all values for each key in "numerator" and "denominator", and emits the margin for each key at the end of window.
 * <p>
 * <br>
 * Margin Formula used by this operator: 1 - numerator/denominator.
 * The values are added for each key within the window and for each stream.<br>
 * <br>
 * <b>Ports</b>:<br>
 * <b>numerator</b>: expects KeyValPair&lt;K,V&gt;<br>
 * <b>denominator</b>: expects KeyValPair&lt;K,V&gt;<br>
 * <b>margin</b>: emits HashMap&lt;K,Double&gt;, one entry per key per window<br>
 * <br>
 * <b>Properties</b>:<br>
 * <b>inverse</b>: if set to true the key in the filter will block tuple<br>
 * <b>filterBy</b>: List of keys to filter on<br>
 * <br>
 * @displayName Margin Key Value
 * @category Math
 * @tags sum, division, numeric, key value
 * @since 0.3.3
 */
public class MarginKeyVal<K, V extends Number> extends BaseNumberKeyValueOperator<K, V> {
    /**
    * Numerator input port that takes a key value pair.
    */
    public final transient DefaultInputPort<KeyValPair<K, V>> numerator = new DefaultInputPort<KeyValPair<K, V>>() {
        /**
         * Adds tuple to the numerator hash.
         */
        @Override
        public void process(KeyValPair<K, V> tuple) {
            addTuple(tuple, numerators);
        }

        /**
         * Set StreamCodec used for partitioning.
         */
        @Override
        public StreamCodec<KeyValPair<K, V>> getStreamCodec() {
            return getKeyValPairStreamCodec();
        }
    };

    /**
    * Denominator input port that takes a key value pair.
    */
    public final transient DefaultInputPort<KeyValPair<K, V>> denominator = new DefaultInputPort<KeyValPair<K, V>>() {
        /**
         * Adds tuple to the denominator hash.
         */
        @Override
        public void process(KeyValPair<K, V> tuple) {
            addTuple(tuple, denominators);
        }

        /**
         * Set StreamCodec used for partitioning.
         */
        @Override
        public StreamCodec<KeyValPair<K, V>> getStreamCodec() {
            return getKeyValPairStreamCodec();
        }
    };

    /**
     * Adds the value for each key.
     *
     * @param tuple
     * @param map
     */
    public void addTuple(KeyValPair<K, V> tuple, Map<K, MutableDouble> map) {
        K key = tuple.getKey();
        if (!doprocessKey(key) || (tuple.getValue() == null)) {
            return;
        }
        MutableDouble val = map.get(key);
        if (val == null) {
            val = new MutableDouble(0.0);
            map.put(cloneKey(key), val);
        }
        val.add(tuple.getValue().doubleValue());
    }

    /**
    * Output margin port that emits Key Value pairs.
    */
    public final transient DefaultOutputPort<KeyValPair<K, V>> margin = new DefaultOutputPort<KeyValPair<K, V>>();

    protected HashMap<K, MutableDouble> numerators = new HashMap<K, MutableDouble>();
    protected HashMap<K, MutableDouble> denominators = new HashMap<K, MutableDouble>();
    protected boolean percent = false;

    /**
     * getter function for percent
     *
     * @return percent
     */
    public boolean getPercent() {
        return percent;
    }

    /**
     * setter function for percent
     *
     * @param val
     *          sets percent
     */
    public void setPercent(boolean val) {
        percent = val;
    }

    /**
     * Generates tuples for each key and emits them. Only keys that are in the
     * denominator are iterated on If the key is only in the numerator, it gets
     * ignored (cannot do divide by 0) Clears internal data
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    @Override
    public void endWindow() {
        Double val;
        for (Map.Entry<K, MutableDouble> e : denominators.entrySet()) {
            K key = e.getKey();
            MutableDouble nval = numerators.get(key);
            if (nval == null) {
                nval = new MutableDouble(0.0);
            } else {
                numerators.remove(key); // so that all left over keys can be reported
            }
            if (percent) {
                val = (1 - nval.doubleValue() / e.getValue().doubleValue()) * 100;
            } else {
                val = 1 - nval.doubleValue() / e.getValue().doubleValue();
            }

            margin.emit(new KeyValPair(key, getValue(val.doubleValue())));
        }

        numerators.clear();
        denominators.clear();
    }
}