com.datatorrent.lib.stream.Counter Maven / Gradle / Ivy
/**
* 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.stream;
import com.datatorrent.api.Context.OperatorContext;
import com.datatorrent.api.DefaultInputPort;
import com.datatorrent.api.DefaultOutputPort;
import com.datatorrent.api.Operator;
import com.datatorrent.api.Operator.Unifier;
/**
* An implementation of Operator and Unifier that counts the number of tuples delivered to it in each window and emits the count.
*
* This is a pass through operator
*
* StateFull : Yes, tuples are counted over application window.
* Partitions : Yes, count is unified at output port.
* Ports:
* input: expects Object
* output: emits Integer
*
* @displayName Counter
* @category Stream Manipulators
* @tags integer, object, count
* @since 0.3.3
*/
public class Counter implements Operator, Unifier
{
/**
* Input port that takes objects to be counted in each window.
*/
public final transient DefaultInputPort
© 2015 - 2025 Weber Informatics LLC | Privacy Policy