/*
* 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.flink.streaming.api.functions.windowing.delta.extractor;
import java.io.Serializable;
import org.apache.flink.annotation.Internal;
/**
* Extractors allow to extract/convert one type to another. They are mostly used
* to extract some fields out of a more complex structure (Tuple/Array) to run
* further calculation on the extraction result.
*
* @param <FROM>
* The input data type.
* @param <TO>
* The output data type.
*/
@Internal
public interface Extractor<FROM, TO> extends Serializable {
/**
* Extracts/Converts the given input to an object of the output type.
*
* @param in
* the input data
* @return the extracted/converted data
*/
TO extract(FROM in);
}