dawidwys commented on code in PR #27602: URL: https://github.com/apache/flink/pull/27602#discussion_r2832107889
########## flink-table/flink-table-runtime/src/main/java/org/apache/flink/table/runtime/operators/sink/SortedLongSerializer.java: ########## @@ -0,0 +1,115 @@ +/* + * 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.operators.sink; + +import org.apache.flink.annotation.Internal; +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 org.apache.flink.util.MathUtils; + +import java.io.IOException; + +/** + * A serializer for {@code Long} that produces a lexicographically sortable byte representation. + * + * <p>Standard big-endian long serialization does not maintain numeric ordering for negative values + * in lexicographic byte comparison because negative numbers have their sign bit set (1), which + * makes them appear greater than positive numbers (sign bit 0) in unsigned byte comparison. + * + * <p>This serializer flips the sign bit during serialization, converting from signed to unsigned + * ordering. This ensures that when iterating over keys in a sorted state backend (like RocksDB), + * the entries are returned in numeric order. + * + * @see org.apache.flink.streaming.api.operators.TimerSerializer + */ +@Internal +public final class SortedLongSerializer extends TypeSerializerSingleton<Long> { + + private static final long serialVersionUID = 1L; + + /** Sharable instance of the SortedLongSerializer. */ + public static final SortedLongSerializer INSTANCE = new SortedLongSerializer(); + + private static final Long ZERO = 0L; + + @Override + public boolean isImmutableType() { + return true; + } + + @Override + public Long createInstance() { + return ZERO; + } + + @Override + public Long copy(Long from) { + return from; + } + + @Override + public Long copy(Long from, Long reuse) { + return from; + } + + @Override + public int getLength() { + return Long.BYTES; + } + + @Override + public void serialize(Long record, DataOutputView target) throws IOException { + target.writeLong(MathUtils.flipSignBit(record)); Review Comment: Are you suggesting timers don't work in Flink? This is copied from `org.apache.flink.streaming.api.operators.TimerSerializer` -- 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]
