org.apache.storm.topology.IWindowedBolt 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 org.apache.storm.topology;
import java.util.Map;
import org.apache.storm.task.OutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.windowing.TimestampExtractor;
import org.apache.storm.windowing.TupleWindow;
/**
* A bolt abstraction for supporting time and count based sliding & tumbling windows.
*/
public interface IWindowedBolt extends IComponent {
/**
* This is similar to the
* {@link org.apache.storm.task.IBolt#prepare(Map, TopologyContext, OutputCollector)} except
* that while emitting, the tuples are automatically anchored to the tuples in the inputWindow.
*/
void prepare(Map topoConf, TopologyContext context, OutputCollector collector);
/**
* Process the tuple window and optionally emit new tuples based on the tuples in the input
* window.
*/
void execute(TupleWindow inputWindow);
void cleanup();
/**
* Return a {@link TimestampExtractor} for extracting timestamps from a
* tuple for event time based processing, or null for processing time.
*
* @return the timestamp extractor
*/
TimestampExtractor getTimestampExtractor();
}