epotyom commented on code in PR #13568: URL: https://github.com/apache/lucene/pull/13568#discussion_r1710300104
########## lucene/sandbox/src/java/org/apache/lucene/sandbox/facet/cutters/LongValueFacetCutter.java: ########## @@ -0,0 +1,173 @@ +/* + * 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.sandbox.facet.cutters; + +import java.io.IOException; +import java.util.concurrent.atomic.AtomicInteger; +import java.util.concurrent.locks.Lock; +import java.util.concurrent.locks.ReentrantReadWriteLock; +import java.util.function.IntSupplier; +import org.apache.lucene.facet.taxonomy.FacetLabel; +import org.apache.lucene.index.DocValues; +import org.apache.lucene.index.LeafReaderContext; +import org.apache.lucene.index.SortedNumericDocValues; +import org.apache.lucene.internal.hppc.IntLongHashMap; +import org.apache.lucene.internal.hppc.LongIntHashMap; +import org.apache.lucene.sandbox.facet.labels.OrdToLabel; + +/** + * {@link FacetCutter} and {@link OrdToLabel} for distinct long values. + * + * <p>TODO: This class is quite inefficient. Will optimise later. + * + * <p>TODO: add support for other value sources e.g: LongValues + */ +public final class LongValueFacetCutter implements FacetCutter, OrdToLabel { + private final String field; + // TODO: consider alternatives if this is a bottleneck + private final LongIntHashMapSyncCompute valueToOrdMap; + private IntLongHashMap ordToValueMap; + private final AtomicInteger maxOrdinal; + + /** + * Constructor. + * + * @param field field name to read long values from. + */ + public LongValueFacetCutter(String field) { + this.field = field; + valueToOrdMap = new LongIntHashMapSyncCompute(); + ordToValueMap = null; + maxOrdinal = new AtomicInteger(-1); + } + + @Override + public LeafFacetCutter createLeafCutter(LeafReaderContext context) throws IOException { + SortedNumericDocValues docValues = DocValues.getSortedNumeric(context.reader(), field); + return new LeafFacetCutter() { + int docValueCount; + long lastDocValue; + int docValueCursor; + + @Override + public boolean advanceExact(int doc) throws IOException { + if (docValues.advanceExact(doc)) { + docValueCount = docValues.docValueCount(); + docValueCursor = 0; + return true; + } + return false; + } + + @Override + public int nextOrd() throws IOException { + while (docValueCursor++ < docValueCount) { + long value = docValues.nextValue(); + // SortedNumericDocValues can have duplicates, but values are sorted, so we only need to + // check previous value to remove duplicates + if (docValueCursor == 1 || value != lastDocValue) { + lastDocValue = value; + return valueToOrdMap.computeIfAbsent(value, maxOrdinal::incrementAndGet); + } + } + return NO_MORE_ORDS; + } + }; + } + + @Override + public FacetLabel getLabel(int ordinal) { + if (ordToValueMap == null) { + buildOrdToValueMap(); + } + if (ordToValueMap.containsKey(ordinal)) { + return new FacetLabel(String.valueOf(ordToValueMap.get(ordinal))); + } + assert false + : "ordinal=" + + ordinal + + ", ordToValueMap.size=" + + ordToValueMap.size() + + ", valueToOrdMap.size=" + + valueToOrdMap.size(); + return null; + } + + /** + * Get value by ordinal. Should only be called after collection phase. + * + * <p>TODO: we need it to tie break sort by value. Alternatively we can sort by label (then we + * don't need this method), but we would have to convert FacetLabel to "long" to have the same + * order... Overall, it is probably not important to tie break by value, and we can tie break by + * ord same as for other facets; but for now we don't want to change results order just in case. + * + * @param ordinal facet ordinal. + * @return long value + */ + public long getValue(int ordinal) { + // TODO: do we want to create #finish method that called by #reduce to build the map? + if (ordToValueMap == null) { + buildOrdToValueMap(); + } + return ordToValueMap.get(ordinal); + } + + private void buildOrdToValueMap() { + ordToValueMap = new IntLongHashMap(valueToOrdMap.size()); + for (LongIntHashMap.LongIntCursor cursor : valueToOrdMap) { + ordToValueMap.put(cursor.value, cursor.key); + } + } + + @Override + public FacetLabel[] getLabels(int[] ordinals) throws IOException { + FacetLabel[] facetLabels = new FacetLabel[ordinals.length]; + for (int i = 0; i < ordinals.length; i++) { + facetLabels[i] = getLabel(ordinals[i]); + } + return facetLabels; + } + + private static class LongIntHashMapSyncCompute extends LongIntHashMap { + private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock(); + private final Lock r = rwl.readLock(); + private final Lock w = rwl.writeLock(); + + public int computeIfAbsent(long key, IntSupplier valueSupplier) { + r.lock(); + int value = super.getOrDefault(key, -1); + r.unlock(); Review Comment: Yes - will do, thanks! -- 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
