Sxnan commented on code in PR #20147: URL: https://github.com/apache/flink/pull/20147#discussion_r932020850
########## flink-streaming-java/src/main/java/org/apache/flink/streaming/api/datastream/CachedDataStream.java: ########## @@ -0,0 +1,65 @@ +/* + * 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.datastream; + +import org.apache.flink.annotation.PublicEvolving; +import org.apache.flink.api.dag.Transformation; +import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment; +import org.apache.flink.streaming.api.transformations.CacheTransformation; + +/** + * {@link CachedDataStream} represents a {@link DataStream} whose intermediate result will be cached + * at the first time when it is computed. And the cached intermediate result can be used in later + * job that using the same {@link CachedDataStream} to avoid re-computing the intermediate result. + * + * @param <T> The type of the elements in this stream. + */ +@PublicEvolving +public class CachedDataStream<T> extends DataStream<T> implements AutoCloseable { + /** + * Create a new {@link CachedDataStream} in the given execution environment that wrap the given + * physical transformation to indicates that the transformation should be cached. + * + * @param environment The StreamExecutionEnvironment + * @param transformation The physical transformation whose intermediate result should be cached. + */ + public CachedDataStream( + StreamExecutionEnvironment environment, Transformation<T> transformation) { + super( + environment, + new CacheTransformation<>( + transformation, + String.format("Cache: %s", transformation.getName()), + transformation.getOutputType(), + transformation.getParallelism())); + + final CacheTransformation<T> t = (CacheTransformation<T>) this.getTransformation(); + environment.addCache(t.getIntermediateDataSetID(), t); + } + + /** + * Invalidate the cache intermediate result of this DataStream to release the physical + * resources. Users are not required to invoke this method to release physical resources unless + * they want to. The CachedDataStream should not be used after it is closed. + */ + @Override + public void close() throws Exception { Review Comment: I think we can go for `invalidate`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
