/*
* 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.beam.runners.direct;
import org.apache.beam.sdk.util.WindowedValue;
/**
* An evaluator of a specific application of a transform. Will be used for at least one
* {@link CommittedBundle}.
*
* @param <InputT> the type of elements that will be passed to {@link #processElement}
*/
interface TransformEvaluator<InputT> {
/**
* Process an element in the input {@link CommittedBundle}.
*
* @param element the element to process
*/
void processElement(WindowedValue<InputT> element) throws Exception;
/**
* Finish processing the bundle of this {@link TransformEvaluator}.
*
* <p>After {@link #finishBundle()} is called, the {@link TransformEvaluator} will not be reused,
* and no more elements will be processed.
*
* @return an {@link TransformResult} containing the results of this bundle evaluation.
*/
TransformResult<InputT> finishBundle() throws Exception;
}