Airblader commented on a change in pull request #17186: URL: https://github.com/apache/flink/pull/17186#discussion_r707193078
########## File path: flink-table/flink-table-common/src/main/java/org/apache/flink/table/types/inference/strategies/RepeatingSequenceInputTypeStrategy.java ########## @@ -0,0 +1,125 @@ +/* + * 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.table.types.inference.strategies; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.table.functions.FunctionDefinition; +import org.apache.flink.table.types.DataType; +import org.apache.flink.table.types.inference.ArgumentCount; +import org.apache.flink.table.types.inference.ArgumentTypeStrategy; +import org.apache.flink.table.types.inference.CallContext; +import org.apache.flink.table.types.inference.InputTypeStrategy; +import org.apache.flink.table.types.inference.Signature; + +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; +import java.util.Objects; +import java.util.Optional; + +/** + * {@link InputTypeStrategy} composed of an arbitrarily often repeating list of {@link + * ArgumentTypeStrategy}s. + */ +@Internal +public class RepeatingSequenceInputTypeStrategy implements InputTypeStrategy { + + private final List<ArgumentTypeStrategy> argumentStrategies; + + public RepeatingSequenceInputTypeStrategy(List<ArgumentTypeStrategy> argumentStrategies) { + this.argumentStrategies = argumentStrategies; + } + + @Override + public ArgumentCount getArgumentCount() { + return new ArgumentCount() { + @Override + public boolean isValidCount(int count) { + return count % argumentStrategies.size() == 0; + } + + @Override + public Optional<Integer> getMinCount() { + return Optional.empty(); + } + + @Override + public Optional<Integer> getMaxCount() { + return Optional.empty(); + } + }; + } + + @Override + public Optional<List<DataType>> inferInputTypes( + CallContext callContext, boolean throwOnFailure) { + final List<DataType> dataTypes = callContext.getArgumentDataTypes(); + final List<DataType> inferredDataTypes = new ArrayList<>(dataTypes.size()); + + for (int i = 0; i < callContext.getArgumentDataTypes().size(); i++) { + final ArgumentTypeStrategy argumentStrategy = + argumentStrategies.get(i % argumentStrategies.size()); + + final Optional<DataType> inferredDataType = + argumentStrategy.inferArgumentType(callContext, i, throwOnFailure); + if (!inferredDataType.isPresent()) { + return Optional.empty(); + } + + inferredDataTypes.add(inferredDataType.get()); + } + + return Optional.of(inferredDataTypes); + } + + @Override + public List<Signature> getExpectedSignatures(FunctionDefinition definition) { + final List<Signature.Argument> arguments = new ArrayList<>(); + for (int i = 0; i < argumentStrategies.size(); i++) { + final Signature.Argument argument = + argumentStrategies.get(i).getExpectedArgument(definition, i); + arguments.add(argument); + } + + // Unfortunately there is no way to represent the repetition in the signature + final Signature signature = Signature.of(arguments); Review comment: It seems `Signature` wasn't really built for something like this, but I can make it work. -- 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
