streams/src/main/java/org/apache/kafka/streams/state/WindowStore.java

/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.kafka.streams.state;

import org.apache.kafka.common.annotation.InterfaceStability;
import org.apache.kafka.streams.processor.StateStore;

/**
 * A windowed store interface extending {@link StateStore}
 *
 * @param <K> Type of keys
 * @param <V> Type of values
 */
@InterfaceStability.Unstable
public interface WindowStore<K, V> extends StateStore {

    /**
     * Put a key-value pair with the current wall-clock time as the timestamp
     * into the corresponding window
     */
    void put(K key, V value);

    /**
     * Put a key-value pair with the given timestamp into the corresponding window
     */
    void put(K key, V value, long timestamp);

    /**
     * Get all the key-value pairs with the given key and the time range from all
     * the existing windows.
     */
    WindowStoreIterator<V> fetch(K key, long timeFrom, long timeTo);
}