| /** |
| * 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.HashMap; |
| import java.util.Map; |
| |
| import org.apache.apex.malhar.lib.util.BaseMatchOperator; |
| |
| import com.datatorrent.api.DefaultInputPort; |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.api.annotation.OperatorAnnotation; |
| |
| /** |
| * This operator filters the incoming stream of key value pairs by obtaining the values corresponding to a specified key, |
| * and comparing those values to a specified number. The first key value pair, in each window, to satisfy the comparison is emitted. |
| * <p> |
| * A compare metric on a Number tuple based on the property "key", "value", and "cmp"; the first match is emitted. |
| * The comparison is done by getting double value from the Number. |
| * </p> |
| * <p> |
| * This module is a pass through<br> |
| * The operators by default assumes immutable keys. If the key is mutable, use cloneKey to make a copy<br> |
| * <br> |
| * <b>StateFull : Yes, </b> tuple are processed in current window. <br> |
| * <b>Partitions : No, </b>will yield wrong results. <br> |
| * <br> |
| * <br> |
| * <b>Ports</b>:<br> |
| * <b>data</b>: expects Map<K,V extends Number><br> |
| * <b>first</b>: emits HashMap<K,V><br> |
| * <br> |
| * <b>Properties</b>:<br> |
| * <b>key</b>: The key on which compare is done<br> |
| * <b>value</b>: The value to compare with<br> |
| * <b>cmp</b>: The compare function. Supported values are "lte", "lt", "eq", "neq", "gt", "gte". Default is "eq"<br> |
| * <br> |
| * <b>Specific compile time checks</b>:<br> |
| * Key must be non empty<br> |
| * Value must be able to convert to a "double"<br> |
| * Compare string, if specified, must be one of "lte", "lt", "eq", "neq", "gt", "gte"<br> |
| * <br> |
| * </p> |
| * |
| * @displayName Emit First Match (Number) |
| * @category Rules and Alerts |
| * @tags filter, key value, numeric |
| * |
| * @since 0.3.2 |
| * @deprecated |
| */ |
| @Deprecated |
| @OperatorAnnotation(partitionable = false) |
| public class FirstMatchMap<K, V extends Number> extends BaseMatchOperator<K,V> |
| { |
| /** |
| * Tuple emitted flag. |
| */ |
| boolean emitted = false; |
| |
| /** |
| * The port on which key value pairs are received. |
| */ |
| public final transient DefaultInputPort<Map<K, V>> data = new DefaultInputPort<Map<K, V>>() |
| { |
| /** |
| * Checks if required key,val pair exists in the HashMap. If so tuple is emitted, and emitted flag is set |
| * to true |
| */ |
| @Override |
| public void process(Map<K, V> tuple) |
| { |
| if (emitted) { |
| return; |
| } |
| V val = tuple.get(getKey()); |
| if (val == null) { // skip if key does not exist |
| return; |
| } |
| if (compareValue(val.doubleValue())) { |
| first.emit(cloneTuple(tuple)); |
| emitted = true; |
| } |
| } |
| }; |
| |
| /** |
| * The output port on which the first satisfying key value pair is emitted. |
| */ |
| public final transient DefaultOutputPort<HashMap<K, V>> first = new DefaultOutputPort<HashMap<K, V>>(); |
| |
| /** |
| * Resets emitted flag to false |
| * @param windowId |
| */ |
| @Override |
| public void beginWindow(long windowId) |
| { |
| emitted = false; |
| } |
| } |