org.apache.kafka.streams.state.TimestampedWindowStore Maven / Gradle / Ivy
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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,
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package org.apache.kafka.streams.state;
import org.apache.kafka.streams.kstream.Windowed;
/**
* Interface for storing the aggregated values of fixed-size time windows.
*
* Note, that the stores's physical key type is {@link Windowed Windowed<K>}.
* In contrast to a {@link WindowStore} that stores plain windowedKeys-value pairs,
* a {@code TimestampedWindowStore} stores windowedKeys-(value/timestamp) pairs.
*
* While the window start- and end-timestamp are fixed per window, the value-side timestamp is used
* to store the last update timestamp of the corresponding window.
*
* @param Type of keys
* @param Type of values
*/
public interface TimestampedWindowStore extends WindowStore> { }