afedulov commented on code in PR #20757: URL: https://github.com/apache/flink/pull/20757#discussion_r964810222
########## flink-core/src/main/java/org/apache/flink/api/connector/source/lib/util/GeneratingIteratorSourceReader.java: ########## @@ -0,0 +1,90 @@ +/* + * 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.api.connector.source.lib.util; + +import org.apache.flink.annotation.Experimental; +import org.apache.flink.api.connector.source.ReaderOutput; +import org.apache.flink.api.connector.source.SourceReaderContext; +import org.apache.flink.api.connector.source.lib.GeneratorFunction; +import org.apache.flink.core.io.InputStatus; +import org.apache.flink.util.FlinkRuntimeException; + +import java.util.Iterator; + +import static org.apache.flink.util.Preconditions.checkNotNull; + +/** + * A {@code SourceReader} that takes the values of an iterator, supplied via an {@link + * IteratorSourceSplit}, and applies a {@link GeneratorFunction} to them to perform arbitrary + * transformations. + */ +@Experimental +public class GeneratingIteratorSourceReader< + E, O, IterT extends Iterator<E>, SplitT extends IteratorSourceSplit<E, IterT>> + extends IteratorSourceReaderBase<E, O, IterT, SplitT> { + + private final GeneratorFunction<E, O> generatorFunction; + + public GeneratingIteratorSourceReader( + SourceReaderContext context, GeneratorFunction<E, O> generatorFunction) { + super(context); + this.generatorFunction = checkNotNull(generatorFunction); + } + + // ------------------------------------------------------------------------ + + @Override + public InputStatus pollNext(ReaderOutput<O> output) { + if (iterator != null) { + if (iterator.hasNext()) { + E next = iterator.next(); + try { + O mapped = generatorFunction.map(next); + output.collect(mapped); + } catch (Exception e) { + String message = + String.format( + "A user-provided generator function threw an exception on this input: %s", + next.toString()); + throw new FlinkRuntimeException(message, e); + } + return InputStatus.MORE_AVAILABLE; Review Comment: Added. -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
