epotyom commented on code in PR #14204: URL: https://github.com/apache/lucene/pull/14204#discussion_r1950866681
########## lucene/facet/src/java/org/apache/lucene/facet/histogram/HistogramCollector.java: ########## @@ -0,0 +1,252 @@ +/* + * 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.lucene.facet.histogram; + +import java.io.IOException; +import org.apache.lucene.index.DocValues; +import org.apache.lucene.index.DocValuesSkipper; +import org.apache.lucene.index.DocValuesType; +import org.apache.lucene.index.FieldInfo; +import org.apache.lucene.index.LeafReaderContext; +import org.apache.lucene.index.NumericDocValues; +import org.apache.lucene.index.SortedNumericDocValues; +import org.apache.lucene.internal.hppc.LongIntHashMap; +import org.apache.lucene.search.CollectionTerminatedException; +import org.apache.lucene.search.Collector; +import org.apache.lucene.search.LeafCollector; +import org.apache.lucene.search.Scorable; +import org.apache.lucene.search.ScoreMode; + +final class HistogramCollector implements Collector { Review Comment: > the API is designed around the idea of hierarchical facets I don't think hierarchy is a central piece of the API, it is more like hierarchical facets are also supported if needed. For many facet implementations it is not needed, such as ranges, distinct long values, etc. I briefly looked at the code and I think it fits into the sandbox module API use case. I believe all you need is to implement FacetCutter (`#createLeafCutter`) and LeafFacetCutter (`#advanceExact` and `#nextOrd`) interfaces, which return bucket indexes as facet ordinals. What you would get for free is counting, or computing other aggregations based on numeric fields for the doc (FacetRecorder implementations); sorting/topN buckets by count or aggregation (`OrdinaIterator`s). You could also implement `OrdToLabel` interface to do the math explained in HistogramCollectorManager's javadoc and return String representations of bucket ranges. That being said, if you don't think that this additional functionality is useful, then there is probably no reason to use the new API, which is more flexible at a cost of creating more abstractions. -- 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: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
