gortiz commented on code in PR #10191: URL: https://github.com/apache/pinot/pull/10191#discussion_r1133696040
########## pinot-segment-spi/src/main/java/org/apache/pinot/segment/spi/index/IndexType.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.pinot.segment.spi.index; + +import java.util.Map; +import javax.annotation.Nullable; +import org.apache.pinot.segment.spi.ColumnMetadata; +import org.apache.pinot.segment.spi.creator.IndexCreationContext; +import org.apache.pinot.segment.spi.index.column.ColumnIndexContainer; +import org.apache.pinot.segment.spi.store.SegmentDirectory; +import org.apache.pinot.spi.config.table.IndexConfig; +import org.apache.pinot.spi.config.table.TableConfig; +import org.apache.pinot.spi.data.Schema; + + +/** + * TODO: implement mutable indexes. + * @param <C> the class that represents how this object is configured. + * @param <IR> the {@link IndexReader} subclass that should be used to read indexes of this type. + * @param <IC> the {@link IndexCreator} subclass that should be used to create indexes of this type. + */ +public interface IndexType<C extends IndexConfig, IR extends IndexReader, IC extends IndexCreator> { + + /** + * The unique id that identifies this index type. + * <p>The returned value for each index should be constant across different Pinot versions as it is used as:</p> + * + * <ul> + * <li>They key used when the index is registered in IndexService.</li> + * <li>The internal identification in v1 files and metadata persisted on disk.</li> + * <li>The default toString implementation.</li> + * <li>The key that identifies the index config in the indexes section inside + * {@link org.apache.pinot.spi.config.table.FieldConfig}, although specific index types may choose to read other + * names (for example, <code>inverted_index</code> may read <code>inverted</code> key.</li> + * </ul> + */ + String getId(); + + Class<C> getIndexConfigClass(); + + /** + * The default config when it is not explicitly defined by the user. + */ + C getDefaultConfig(); + + C getConfig(TableConfig tableConfig, Schema schema); + + /** + * Optional method that can be implemented to ignore the index creation. + * + * Sometimes it doesn't make sense to create an index, even when the user explicitly asked for it. For example, an + * inverted index shouldn't be created when the column is sorted. + * + * Apache Pinot will call this method once all index configurations have been parsed and it is included in the Review Comment: I prefer to be too generic than too specific. Using an IDE (and even github!) it is easy to know who calls a function, so an interested reader can calculate the complete list of callers in real time. But in the too specific case, it may happen that in a future the caller changes to another class and it would be very easy to forget to change this javadoc, which would make it incorrect. -- 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
