dianfu commented on a change in pull request #9977: [FLINK-14497][python] Support primitive data types in Python user-defined functions URL: https://github.com/apache/flink/pull/9977#discussion_r338373998
########## File path: flink-python/src/main/java/org/apache/flink/table/runtime/typeutils/serializers/StringSerializer.java ########## @@ -0,0 +1,121 @@ +/* + * 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.runtime.typeutils.serializers; + +import org.apache.flink.api.common.typeutils.SimpleTypeSerializerSnapshot; +import org.apache.flink.api.common.typeutils.TypeSerializerSnapshot; +import org.apache.flink.api.common.typeutils.base.TypeSerializerSingleton; +import org.apache.flink.core.memory.DataInputView; +import org.apache.flink.core.memory.DataOutputView; + +import java.io.IOException; +import java.nio.charset.StandardCharsets; + +/** + * <p>We create the StringSerializer instead of using the StringSerializer of flink-core module + * because the StringSerializer of flink-core module serialize every Char of String in serialize method and deserialize the Char + * to build the String.It make sense in Java. However in Python, Python does not have a so-called char to construct a string. + * When getting a ASCII int array, Python need to specify character set (etc. UTF-8) to build a str Which is hard to use the + * method of the StringSerializer of flink-core module.</p> + * + * <p>So we create this StringSerializer (only used in Java and Python data communication in udf). + * + * <p>StringSerializer for String. + */ +public class StringSerializer extends TypeSerializerSingleton<String> { Review comment: Could we reuse the StringSerializer in flink-core momdule? ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
