gortiz commented on code in PR #12223: URL: https://github.com/apache/pinot/pull/12223#discussion_r1450096545
########## pinot-segment-local/src/main/java/org/apache/pinot/segment/local/segment/index/dictionary/DictionaryInternerHolder.java: ########## @@ -0,0 +1,64 @@ +/** + * 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.pinot.segment.local.segment.index.dictionary; + +import java.util.Arrays; +import java.util.Map; +import java.util.concurrent.ConcurrentHashMap; +import org.apache.pinot.spi.utils.FALFInterner; + + +/** + * This class holds the dictionary interners. It is currently used only for OnHeapStringDictionary. + */ +public class DictionaryInternerHolder { + private static final DictionaryInternerHolder INSTANCE = new DictionaryInternerHolder(); + + // Map containing tableName + columnName as key and the interner as value. The interner is common across all the + // segments for a given table. + private Map<String, FALFInterner<String>> _strInternerInfoMap; + private Map<String, FALFInterner<byte[]>> _byteInternerInfoMap; + + private DictionaryInternerHolder() { + _strInternerInfoMap = new ConcurrentHashMap<>(); + _byteInternerInfoMap = new ConcurrentHashMap<>(); + } + + public static DictionaryInternerHolder getInstance() { + return INSTANCE; + } + + public FALFInterner<String> getStrInterner(String columnIdentifier, int capacity) { + return _strInternerInfoMap.computeIfAbsent(columnIdentifier, k -> new FALFInterner<>(capacity)); + } + + public FALFInterner<byte[]> getByteInterner(String columnIdentifier, int capacity) { + return _byteInternerInfoMap.computeIfAbsent(columnIdentifier, k -> new FALFInterner<>(capacity, Arrays::hashCode)); + } + + public String createIdentifier(String tableName, String colName) { + int initialCapacity = tableName.length() + colName.length() + 1; + StringBuilder identifierBuilder = new StringBuilder(initialCapacity); + identifierBuilder.append(tableName); + identifierBuilder.append(':'); + identifierBuilder.append(colName); Review Comment: It is not necessary to add a string builder here. `return tableName + ":" + colName` is just fine. First, this is not the hot path. It will only be used when the index is created, not when it is used. Second, both javac and the JIT are able to optimize these expressions quite well. -- 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: commits-unsubscr...@pinot.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
