LakshSingla commented on code in PR #16068: URL: https://github.com/apache/druid/pull/16068#discussion_r1540406635
########## processing/src/main/java/org/apache/druid/query/groupby/epinephelinae/column/IdToDimensionConverter.java: ########## @@ -0,0 +1,56 @@ +/* + * 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.druid.query.groupby.epinephelinae.column; + +/** + * Converts back the dictionaryId to the dimension value. The implementations might or might not handle + * {@link GroupByColumnSelectorStrategy#GROUP_BY_MISSING_VALUE}. The callers should handle those values appropriately on + * their own, and filter those out before trying to convert the dictionary id back to value. + * + * The encoding - decoding workflow looks like: + * + * Encoding + * 1. {@link DimensionToIdConverter} extracts the multi-value holder for the given row, which get's stored somewhere + * 2. For each entry in the multi-value object, the value gets encoded into a dictionaryId, using {@link DimensionToIdConverter#getIndividualValueDictId} + * 3. The callers can use this integer dictionaryID to materialize the results somewhere + * + * Decoding + * 1. The materialized dictionary id is deserialized back to an int, and then decoded into value using {@link #idToKey} + * + * @see DimensionToIdConverter for converting the dimensions to dictionary ids + * + * @param <DimensionType> Type of the dimension's values + */ +public interface IdToDimensionConverter<DimensionType> Review Comment: While refactoring, I realized that `IdLookup` is for the replacement of `DimensionToIdConvertor`. After separating out the strategy, it should be simple to replace `DimensionToIdConverter` with `IdLookup` -- 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...@druid.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@druid.apache.org For additional commands, e-mail: commits-h...@druid.apache.org
