org.apache.kafka.streams.processor.api.FixedKeyProcessorSupplier 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,
* 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.processor.api;
import org.apache.kafka.streams.processor.ConnectedStoreProvider;
import java.util.function.Supplier;
/**
* A processor supplier that can create one or more {@link FixedKeyProcessor} instances.
*
* The supplier should always generate a new instance each time {@link FixedKeyProcessorSupplier#get()} gets called. Creating
* a single {@link FixedKeyProcessor} object and returning the same object reference in {@link FixedKeyProcessorSupplier#get()} would be
* a violation of the supplier pattern and leads to runtime exceptions.
*
* @param the type of input keys
* @param the type of input values
* @param the type of output values
*/
@FunctionalInterface
public interface FixedKeyProcessorSupplier
extends ConnectedStoreProvider, Supplier> {
/**
* Return a newly constructed {@link FixedKeyProcessor} instance.
* The supplier should always generate a new instance each time {@code FixedKeyProcessorSupplier#get()} gets called.
*
* Creating a single {@link FixedKeyProcessor} object and returning the same object reference in {@code FixedKeyProcessorSupplier#get()}
* is a violation of the supplier pattern and leads to runtime exceptions.
*
* @return a new {@link FixedKeyProcessor} instance
*/
FixedKeyProcessor get();
}