| package org.apache.lucene.search; |
| |
| /* |
| * 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. |
| */ |
| |
| import java.io.IOException; |
| |
| import org.apache.lucene.index.AtomicReaderContext; |
| import org.apache.lucene.index.BinaryDocValues; |
| import org.apache.lucene.index.SortedDocValues; |
| import org.apache.lucene.search.FieldCache.DoubleParser; |
| import org.apache.lucene.search.FieldCache.FloatParser; |
| import org.apache.lucene.search.FieldCache.IntParser; |
| import org.apache.lucene.search.FieldCache.LongParser; |
| import org.apache.lucene.util.Bits; |
| import org.apache.lucene.util.BytesRef; |
| |
| /** |
| * Expert: a FieldComparator compares hits so as to determine their |
| * sort order when collecting the top results with {@link |
| * TopFieldCollector}. The concrete public FieldComparator |
| * classes here correspond to the SortField types. |
| * |
| * <p>This API is designed to achieve high performance |
| * sorting, by exposing a tight interaction with {@link |
| * FieldValueHitQueue} as it visits hits. Whenever a hit is |
| * competitive, it's enrolled into a virtual slot, which is |
| * an int ranging from 0 to numHits-1. The {@link |
| * FieldComparator} is made aware of segment transitions |
| * during searching in case any internal state it's tracking |
| * needs to be recomputed during these transitions.</p> |
| * |
| * <p>A comparator must define these functions:</p> |
| * |
| * <ul> |
| * |
| * <li> {@link #compare} Compare a hit at 'slot a' |
| * with hit 'slot b'. |
| * |
| * <li> {@link #setBottom} This method is called by |
| * {@link FieldValueHitQueue} to notify the |
| * FieldComparator of the current weakest ("bottom") |
| * slot. Note that this slot may not hold the weakest |
| * value according to your comparator, in cases where |
| * your comparator is not the primary one (ie, is only |
| * used to break ties from the comparators before it). |
| * |
| * <li> {@link #compareBottom} Compare a new hit (docID) |
| * against the "weakest" (bottom) entry in the queue. |
| * |
| * <li> {@link #setTopValue} This method is called by |
| * {@link TopFieldCollector} to notify the |
| * FieldComparator of the top most value, which is |
| * used by future calls to {@link #compareTop}. |
| * |
| * <li> {@link #compareBottom} Compare a new hit (docID) |
| * against the "weakest" (bottom) entry in the queue. |
| * |
| * <li> {@link #compareTop} Compare a new hit (docID) |
| * against the top value previously set by a call to |
| * {@link #setTopValue}. |
| * |
| * <li> {@link #copy} Installs a new hit into the |
| * priority queue. The {@link FieldValueHitQueue} |
| * calls this method when a new hit is competitive. |
| * |
| * <li> {@link #setNextReader(AtomicReaderContext)} Invoked |
| * when the search is switching to the next segment. |
| * You may need to update internal state of the |
| * comparator, for example retrieving new values from |
| * the {@link FieldCache}. |
| * |
| * <li> {@link #value} Return the sort value stored in |
| * the specified slot. This is only called at the end |
| * of the search, in order to populate {@link |
| * FieldDoc#fields} when returning the top results. |
| * </ul> |
| * |
| * @lucene.experimental |
| */ |
| public abstract class FieldComparator<T> { |
| |
| /** |
| * Compare hit at slot1 with hit at slot2. |
| * |
| * @param slot1 first slot to compare |
| * @param slot2 second slot to compare |
| * @return any N < 0 if slot2's value is sorted after |
| * slot1, any N > 0 if the slot2's value is sorted before |
| * slot1 and 0 if they are equal |
| */ |
| public abstract int compare(int slot1, int slot2); |
| |
| /** |
| * Set the bottom slot, ie the "weakest" (sorted last) |
| * entry in the queue. When {@link #compareBottom} is |
| * called, you should compare against this slot. This |
| * will always be called before {@link #compareBottom}. |
| * |
| * @param slot the currently weakest (sorted last) slot in the queue |
| */ |
| public abstract void setBottom(final int slot); |
| |
| /** |
| * Record the top value, for future calls to {@link |
| * #compareTop}. This is only called for searches that |
| * use searchAfter (deep paging), and is called before any |
| * calls to {@link #setNextReader}. |
| */ |
| public abstract void setTopValue(T value); |
| |
| /** |
| * Compare the bottom of the queue with this doc. This will |
| * only invoked after setBottom has been called. This |
| * should return the same result as {@link |
| * #compare(int,int)}} as if bottom were slot1 and the new |
| * document were slot 2. |
| * |
| * <p>For a search that hits many results, this method |
| * will be the hotspot (invoked by far the most |
| * frequently).</p> |
| * |
| * @param doc that was hit |
| * @return any N < 0 if the doc's value is sorted after |
| * the bottom entry (not competitive), any N > 0 if the |
| * doc's value is sorted before the bottom entry and 0 if |
| * they are equal. |
| */ |
| public abstract int compareBottom(int doc) throws IOException; |
| |
| /** |
| * Compare the top value with this doc. This will |
| * only invoked after setTopValue has been called. This |
| * should return the same result as {@link |
| * #compare(int,int)}} as if topValue were slot1 and the new |
| * document were slot 2. This is only called for searches that |
| * use searchAfter (deep paging). |
| * |
| * @param doc that was hit |
| * @return any N < 0 if the doc's value is sorted after |
| * the bottom entry (not competitive), any N > 0 if the |
| * doc's value is sorted before the bottom entry and 0 if |
| * they are equal. |
| */ |
| public abstract int compareTop(int doc) throws IOException; |
| |
| /** |
| * This method is called when a new hit is competitive. |
| * You should copy any state associated with this document |
| * that will be required for future comparisons, into the |
| * specified slot. |
| * |
| * @param slot which slot to copy the hit to |
| * @param doc docID relative to current reader |
| */ |
| public abstract void copy(int slot, int doc) throws IOException; |
| |
| /** |
| * Set a new {@link AtomicReaderContext}. All subsequent docIDs are relative to |
| * the current reader (you must add docBase if you need to |
| * map it to a top-level docID). |
| * |
| * @param context current reader context |
| * @return the comparator to use for this segment; most |
| * comparators can just return "this" to reuse the same |
| * comparator across segments |
| * @throws IOException if there is a low-level IO error |
| */ |
| public abstract FieldComparator<T> setNextReader(AtomicReaderContext context) throws IOException; |
| |
| /** Sets the Scorer to use in case a document's score is |
| * needed. |
| * |
| * @param scorer Scorer instance that you should use to |
| * obtain the current hit's score, if necessary. */ |
| public void setScorer(Scorer scorer) { |
| // Empty implementation since most comparators don't need the score. This |
| // can be overridden by those that need it. |
| } |
| |
| /** |
| * Return the actual value in the slot. |
| * |
| * @param slot the value |
| * @return value in this slot |
| */ |
| public abstract T value(int slot); |
| |
| /** Returns -1 if first is less than second. Default |
| * impl to assume the type implements Comparable and |
| * invoke .compareTo; be sure to override this method if |
| * your FieldComparator's type isn't a Comparable or |
| * if your values may sometimes be null */ |
| @SuppressWarnings("unchecked") |
| public int compareValues(T first, T second) { |
| if (first == null) { |
| if (second == null) { |
| return 0; |
| } else { |
| return -1; |
| } |
| } else if (second == null) { |
| return 1; |
| } else { |
| return ((Comparable<T>) first).compareTo(second); |
| } |
| } |
| |
| /** |
| * Base FieldComparator class for numeric types |
| */ |
| public static abstract class NumericComparator<T extends Number> extends FieldComparator<T> { |
| protected final T missingValue; |
| protected final String field; |
| protected Bits docsWithField; |
| |
| public NumericComparator(String field, T missingValue) { |
| this.field = field; |
| this.missingValue = missingValue; |
| } |
| |
| @Override |
| public FieldComparator<T> setNextReader(AtomicReaderContext context) throws IOException { |
| if (missingValue != null) { |
| docsWithField = FieldCache.DEFAULT.getDocsWithField(context.reader(), field); |
| // optimization to remove unneeded checks on the bit interface: |
| if (docsWithField instanceof Bits.MatchAllBits) { |
| docsWithField = null; |
| } |
| } else { |
| docsWithField = null; |
| } |
| return this; |
| } |
| } |
| |
| /** Parses field's values as double (using {@link |
| * FieldCache#getDoubles} and sorts by ascending value */ |
| public static final class DoubleComparator extends NumericComparator<Double> { |
| private final double[] values; |
| private final DoubleParser parser; |
| private FieldCache.Doubles currentReaderValues; |
| private double bottom; |
| private double topValue; |
| |
| DoubleComparator(int numHits, String field, FieldCache.Parser parser, Double missingValue) { |
| super(field, missingValue); |
| values = new double[numHits]; |
| this.parser = (DoubleParser) parser; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| return Double.compare(values[slot1], values[slot2]); |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| double v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| return Double.compare(bottom, v2); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| double v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| values[slot] = v2; |
| } |
| |
| @Override |
| public FieldComparator<Double> setNextReader(AtomicReaderContext context) throws IOException { |
| // NOTE: must do this before calling super otherwise |
| // we compute the docsWithField Bits twice! |
| currentReaderValues = FieldCache.DEFAULT.getDoubles(context.reader(), field, parser, missingValue != null); |
| return super.setNextReader(context); |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = values[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(Double value) { |
| topValue = value; |
| } |
| |
| @Override |
| public Double value(int slot) { |
| return Double.valueOf(values[slot]); |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| double docValue = currentReaderValues.get(doc); |
| // Test for docValue == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && docValue == 0 && !docsWithField.get(doc)) { |
| docValue = missingValue; |
| } |
| return Double.compare(topValue, docValue); |
| } |
| } |
| |
| /** Parses field's values as float (using {@link |
| * FieldCache#getFloats} and sorts by ascending value */ |
| public static final class FloatComparator extends NumericComparator<Float> { |
| private final float[] values; |
| private final FloatParser parser; |
| private FieldCache.Floats currentReaderValues; |
| private float bottom; |
| private float topValue; |
| |
| FloatComparator(int numHits, String field, FieldCache.Parser parser, Float missingValue) { |
| super(field, missingValue); |
| values = new float[numHits]; |
| this.parser = (FloatParser) parser; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| return Float.compare(values[slot1], values[slot2]); |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| // TODO: are there sneaky non-branch ways to compute sign of float? |
| float v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| return Float.compare(bottom, v2); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| float v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| values[slot] = v2; |
| } |
| |
| @Override |
| public FieldComparator<Float> setNextReader(AtomicReaderContext context) throws IOException { |
| // NOTE: must do this before calling super otherwise |
| // we compute the docsWithField Bits twice! |
| currentReaderValues = FieldCache.DEFAULT.getFloats(context.reader(), field, parser, missingValue != null); |
| return super.setNextReader(context); |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = values[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(Float value) { |
| topValue = value; |
| } |
| |
| @Override |
| public Float value(int slot) { |
| return Float.valueOf(values[slot]); |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| float docValue = currentReaderValues.get(doc); |
| // Test for docValue == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && docValue == 0 && !docsWithField.get(doc)) { |
| docValue = missingValue; |
| } |
| return Float.compare(topValue, docValue); |
| } |
| } |
| |
| /** Parses field's values as int (using {@link |
| * FieldCache#getInts} and sorts by ascending value */ |
| public static final class IntComparator extends NumericComparator<Integer> { |
| private final int[] values; |
| private final IntParser parser; |
| private FieldCache.Ints currentReaderValues; |
| private int bottom; // Value of bottom of queue |
| private int topValue; |
| |
| IntComparator(int numHits, String field, FieldCache.Parser parser, Integer missingValue) { |
| super(field, missingValue); |
| values = new int[numHits]; |
| this.parser = (IntParser) parser; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| return Integer.compare(values[slot1], values[slot2]); |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| int v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| return Integer.compare(bottom, v2); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| int v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| values[slot] = v2; |
| } |
| |
| @Override |
| public FieldComparator<Integer> setNextReader(AtomicReaderContext context) throws IOException { |
| // NOTE: must do this before calling super otherwise |
| // we compute the docsWithField Bits twice! |
| currentReaderValues = FieldCache.DEFAULT.getInts(context.reader(), field, parser, missingValue != null); |
| return super.setNextReader(context); |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = values[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(Integer value) { |
| topValue = value; |
| } |
| |
| @Override |
| public Integer value(int slot) { |
| return Integer.valueOf(values[slot]); |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| int docValue = currentReaderValues.get(doc); |
| // Test for docValue == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && docValue == 0 && !docsWithField.get(doc)) { |
| docValue = missingValue; |
| } |
| return Integer.compare(topValue, docValue); |
| } |
| } |
| |
| /** Parses field's values as long (using {@link |
| * FieldCache#getLongs} and sorts by ascending value */ |
| public static final class LongComparator extends NumericComparator<Long> { |
| private final long[] values; |
| private final LongParser parser; |
| private FieldCache.Longs currentReaderValues; |
| private long bottom; |
| private long topValue; |
| |
| LongComparator(int numHits, String field, FieldCache.Parser parser, Long missingValue) { |
| super(field, missingValue); |
| values = new long[numHits]; |
| this.parser = (LongParser) parser; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| return Long.compare(values[slot1], values[slot2]); |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| // TODO: there are sneaky non-branch ways to compute |
| // -1/+1/0 sign |
| long v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| return Long.compare(bottom, v2); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| long v2 = currentReaderValues.get(doc); |
| // Test for v2 == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && v2 == 0 && !docsWithField.get(doc)) { |
| v2 = missingValue; |
| } |
| |
| values[slot] = v2; |
| } |
| |
| @Override |
| public FieldComparator<Long> setNextReader(AtomicReaderContext context) throws IOException { |
| // NOTE: must do this before calling super otherwise |
| // we compute the docsWithField Bits twice! |
| currentReaderValues = FieldCache.DEFAULT.getLongs(context.reader(), field, parser, missingValue != null); |
| return super.setNextReader(context); |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = values[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(Long value) { |
| topValue = value; |
| } |
| |
| @Override |
| public Long value(int slot) { |
| return Long.valueOf(values[slot]); |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| long docValue = currentReaderValues.get(doc); |
| // Test for docValue == 0 to save Bits.get method call for |
| // the common case (doc has value and value is non-zero): |
| if (docsWithField != null && docValue == 0 && !docsWithField.get(doc)) { |
| docValue = missingValue; |
| } |
| return Long.compare(topValue, docValue); |
| } |
| } |
| |
| /** Sorts by descending relevance. NOTE: if you are |
| * sorting only by descending relevance and then |
| * secondarily by ascending docID, performance is faster |
| * using {@link TopScoreDocCollector} directly (which {@link |
| * IndexSearcher#search} uses when no {@link Sort} is |
| * specified). */ |
| public static final class RelevanceComparator extends FieldComparator<Float> { |
| private final float[] scores; |
| private float bottom; |
| private Scorer scorer; |
| private float topValue; |
| |
| RelevanceComparator(int numHits) { |
| scores = new float[numHits]; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| return Float.compare(scores[slot2], scores[slot1]); |
| } |
| |
| @Override |
| public int compareBottom(int doc) throws IOException { |
| float score = scorer.score(); |
| assert !Float.isNaN(score); |
| return Float.compare(score, bottom); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) throws IOException { |
| scores[slot] = scorer.score(); |
| assert !Float.isNaN(scores[slot]); |
| } |
| |
| @Override |
| public FieldComparator<Float> setNextReader(AtomicReaderContext context) { |
| return this; |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = scores[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(Float value) { |
| topValue = value; |
| } |
| |
| @Override |
| public void setScorer(Scorer scorer) { |
| // wrap with a ScoreCachingWrappingScorer so that successive calls to |
| // score() will not incur score computation over and |
| // over again. |
| if (!(scorer instanceof ScoreCachingWrappingScorer)) { |
| this.scorer = new ScoreCachingWrappingScorer(scorer); |
| } else { |
| this.scorer = scorer; |
| } |
| } |
| |
| @Override |
| public Float value(int slot) { |
| return Float.valueOf(scores[slot]); |
| } |
| |
| // Override because we sort reverse of natural Float order: |
| @Override |
| public int compareValues(Float first, Float second) { |
| // Reversed intentionally because relevance by default |
| // sorts descending: |
| return second.compareTo(first); |
| } |
| |
| @Override |
| public int compareTop(int doc) throws IOException { |
| float docValue = scorer.score(); |
| assert !Float.isNaN(docValue); |
| return Float.compare(docValue, topValue); |
| } |
| } |
| |
| /** Sorts by ascending docID */ |
| public static final class DocComparator extends FieldComparator<Integer> { |
| private final int[] docIDs; |
| private int docBase; |
| private int bottom; |
| private int topValue; |
| |
| DocComparator(int numHits) { |
| docIDs = new int[numHits]; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| // No overflow risk because docIDs are non-negative |
| return docIDs[slot1] - docIDs[slot2]; |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| // No overflow risk because docIDs are non-negative |
| return bottom - (docBase + doc); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| docIDs[slot] = docBase + doc; |
| } |
| |
| @Override |
| public FieldComparator<Integer> setNextReader(AtomicReaderContext context) { |
| // TODO: can we "map" our docIDs to the current |
| // reader? saves having to then subtract on every |
| // compare call |
| this.docBase = context.docBase; |
| return this; |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = docIDs[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(Integer value) { |
| topValue = value; |
| } |
| |
| @Override |
| public Integer value(int slot) { |
| return Integer.valueOf(docIDs[slot]); |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| int docValue = docBase + doc; |
| return Integer.compare(topValue, docValue); |
| } |
| } |
| |
| /** Sorts by field's natural Term sort order, using |
| * ordinals. This is functionally equivalent to {@link |
| * org.apache.lucene.search.FieldComparator.TermValComparator}, but it first resolves the string |
| * to their relative ordinal positions (using the index |
| * returned by {@link FieldCache#getTermsIndex}), and |
| * does most comparisons using the ordinals. For medium |
| * to large results, this comparator will be much faster |
| * than {@link org.apache.lucene.search.FieldComparator.TermValComparator}. For very small |
| * result sets it may be slower. */ |
| public static class TermOrdValComparator extends FieldComparator<BytesRef> { |
| /* Ords for each slot. |
| @lucene.internal */ |
| final int[] ords; |
| |
| /* Values for each slot. |
| @lucene.internal */ |
| final BytesRef[] values; |
| |
| /* Which reader last copied a value into the slot. When |
| we compare two slots, we just compare-by-ord if the |
| readerGen is the same; else we must compare the |
| values (slower). |
| @lucene.internal */ |
| final int[] readerGen; |
| |
| /* Gen of current reader we are on. |
| @lucene.internal */ |
| int currentReaderGen = -1; |
| |
| /* Current reader's doc ord/values. |
| @lucene.internal */ |
| SortedDocValues termsIndex; |
| |
| private final String field; |
| |
| /* Bottom slot, or -1 if queue isn't full yet |
| @lucene.internal */ |
| int bottomSlot = -1; |
| |
| /* Bottom ord (same as ords[bottomSlot] once bottomSlot |
| is set). Cached for faster compares. |
| @lucene.internal */ |
| int bottomOrd; |
| |
| /* True if current bottom slot matches the current |
| reader. |
| @lucene.internal */ |
| boolean bottomSameReader; |
| |
| /* Bottom value (same as values[bottomSlot] once |
| bottomSlot is set). Cached for faster compares. |
| @lucene.internal */ |
| BytesRef bottomValue; |
| |
| /** Set by setTopValue. */ |
| BytesRef topValue; |
| boolean topSameReader; |
| int topOrd; |
| |
| final BytesRef tempBR = new BytesRef(); |
| |
| /** -1 if missing values are sorted first, 1 if they are |
| * sorted last */ |
| final int missingSortCmp; |
| |
| /** Which ordinal to use for a missing value. */ |
| final int missingOrd; |
| |
| /** Creates this, sorting missing values first. */ |
| public TermOrdValComparator(int numHits, String field) { |
| this(numHits, field, false); |
| } |
| |
| /** Creates this, with control over how missing values |
| * are sorted. Pass sortMissingLast=true to put |
| * missing values at the end. */ |
| public TermOrdValComparator(int numHits, String field, boolean sortMissingLast) { |
| ords = new int[numHits]; |
| values = new BytesRef[numHits]; |
| readerGen = new int[numHits]; |
| this.field = field; |
| if (sortMissingLast) { |
| missingSortCmp = 1; |
| missingOrd = Integer.MAX_VALUE; |
| } else { |
| missingSortCmp = -1; |
| missingOrd = -1; |
| } |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| if (readerGen[slot1] == readerGen[slot2]) { |
| return ords[slot1] - ords[slot2]; |
| } |
| |
| final BytesRef val1 = values[slot1]; |
| final BytesRef val2 = values[slot2]; |
| if (val1 == null) { |
| if (val2 == null) { |
| return 0; |
| } |
| return missingSortCmp; |
| } else if (val2 == null) { |
| return -missingSortCmp; |
| } |
| return val1.compareTo(val2); |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| assert bottomSlot != -1; |
| int docOrd = termsIndex.getOrd(doc); |
| if (docOrd == -1) { |
| docOrd = missingOrd; |
| } |
| if (bottomSameReader) { |
| // ord is precisely comparable, even in the equal case |
| return bottomOrd - docOrd; |
| } else if (bottomOrd >= docOrd) { |
| // the equals case always means bottom is > doc |
| // (because we set bottomOrd to the lower bound in |
| // setBottom): |
| return 1; |
| } else { |
| return -1; |
| } |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| int ord = termsIndex.getOrd(doc); |
| if (ord == -1) { |
| ord = missingOrd; |
| values[slot] = null; |
| } else { |
| assert ord >= 0; |
| if (values[slot] == null) { |
| values[slot] = new BytesRef(); |
| } |
| termsIndex.lookupOrd(ord, values[slot]); |
| } |
| ords[slot] = ord; |
| readerGen[slot] = currentReaderGen; |
| } |
| |
| /** Retrieves the SortedDocValues for the field in this segment */ |
| protected SortedDocValues getSortedDocValues(AtomicReaderContext context, String field) throws IOException { |
| return FieldCache.DEFAULT.getTermsIndex(context.reader(), field); |
| } |
| |
| @Override |
| public FieldComparator<BytesRef> setNextReader(AtomicReaderContext context) throws IOException { |
| termsIndex = getSortedDocValues(context, field); |
| currentReaderGen++; |
| |
| if (topValue != null) { |
| // Recompute topOrd/SameReader |
| int ord = termsIndex.lookupTerm(topValue); |
| if (ord >= 0) { |
| topSameReader = true; |
| topOrd = ord; |
| } else { |
| topSameReader = false; |
| topOrd = -ord-2; |
| } |
| } else { |
| topOrd = missingOrd; |
| topSameReader = true; |
| } |
| //System.out.println(" setNextReader topOrd=" + topOrd + " topSameReader=" + topSameReader); |
| |
| if (bottomSlot != -1) { |
| // Recompute bottomOrd/SameReader |
| setBottom(bottomSlot); |
| } |
| |
| return this; |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| bottomSlot = bottom; |
| |
| bottomValue = values[bottomSlot]; |
| if (currentReaderGen == readerGen[bottomSlot]) { |
| bottomOrd = ords[bottomSlot]; |
| bottomSameReader = true; |
| } else { |
| if (bottomValue == null) { |
| // missingOrd is null for all segments |
| assert ords[bottomSlot] == missingOrd; |
| bottomOrd = missingOrd; |
| bottomSameReader = true; |
| readerGen[bottomSlot] = currentReaderGen; |
| } else { |
| final int ord = termsIndex.lookupTerm(bottomValue); |
| if (ord < 0) { |
| bottomOrd = -ord - 2; |
| bottomSameReader = false; |
| } else { |
| bottomOrd = ord; |
| // exact value match |
| bottomSameReader = true; |
| readerGen[bottomSlot] = currentReaderGen; |
| ords[bottomSlot] = bottomOrd; |
| } |
| } |
| } |
| } |
| |
| @Override |
| public void setTopValue(BytesRef value) { |
| // null is fine: it means the last doc of the prior |
| // search was missing this value |
| topValue = value; |
| //System.out.println("setTopValue " + topValue); |
| } |
| |
| @Override |
| public BytesRef value(int slot) { |
| return values[slot]; |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| |
| int ord = termsIndex.getOrd(doc); |
| if (ord == -1) { |
| ord = missingOrd; |
| } |
| |
| if (topSameReader) { |
| // ord is precisely comparable, even in the equal |
| // case |
| //System.out.println("compareTop doc=" + doc + " ord=" + ord + " ret=" + (topOrd-ord)); |
| return topOrd - ord; |
| } else if (ord <= topOrd) { |
| // the equals case always means doc is < value |
| // (because we set lastOrd to the lower bound) |
| return 1; |
| } else { |
| return -1; |
| } |
| } |
| |
| @Override |
| public int compareValues(BytesRef val1, BytesRef val2) { |
| if (val1 == null) { |
| if (val2 == null) { |
| return 0; |
| } |
| return missingSortCmp; |
| } else if (val2 == null) { |
| return -missingSortCmp; |
| } |
| return val1.compareTo(val2); |
| } |
| } |
| |
| /** Sorts by field's natural Term sort order. All |
| * comparisons are done using BytesRef.compareTo, which is |
| * slow for medium to large result sets but possibly |
| * very fast for very small results sets. */ |
| // TODO: should we remove this? who really uses it? |
| public static final class TermValComparator extends FieldComparator<BytesRef> { |
| |
| // sentinels, just used internally in this comparator |
| private static final byte[] MISSING_BYTES = new byte[0]; |
| private static final byte[] NON_MISSING_BYTES = new byte[0]; |
| |
| private BytesRef[] values; |
| private BinaryDocValues docTerms; |
| private Bits docsWithField; |
| private final String field; |
| private BytesRef bottom; |
| private BytesRef topValue; |
| private final BytesRef tempBR = new BytesRef(); |
| |
| // TODO: add missing first/last support here? |
| |
| /** Sole constructor. */ |
| TermValComparator(int numHits, String field) { |
| values = new BytesRef[numHits]; |
| this.field = field; |
| } |
| |
| @Override |
| public int compare(int slot1, int slot2) { |
| final BytesRef val1 = values[slot1]; |
| final BytesRef val2 = values[slot2]; |
| if (val1.bytes == MISSING_BYTES) { |
| if (val2.bytes == MISSING_BYTES) { |
| return 0; |
| } |
| return -1; |
| } else if (val2.bytes == MISSING_BYTES) { |
| return 1; |
| } |
| |
| return val1.compareTo(val2); |
| } |
| |
| @Override |
| public int compareBottom(int doc) { |
| docTerms.get(doc, tempBR); |
| setMissingBytes(doc, tempBR); |
| return compareValues(bottom, tempBR); |
| } |
| |
| @Override |
| public void copy(int slot, int doc) { |
| if (values[slot] == null) { |
| values[slot] = new BytesRef(); |
| } |
| docTerms.get(doc, values[slot]); |
| setMissingBytes(doc, values[slot]); |
| } |
| |
| @Override |
| public FieldComparator<BytesRef> setNextReader(AtomicReaderContext context) throws IOException { |
| docTerms = FieldCache.DEFAULT.getTerms(context.reader(), field, true); |
| docsWithField = FieldCache.DEFAULT.getDocsWithField(context.reader(), field); |
| return this; |
| } |
| |
| @Override |
| public void setBottom(final int bottom) { |
| this.bottom = values[bottom]; |
| } |
| |
| @Override |
| public void setTopValue(BytesRef value) { |
| if (value == null) { |
| throw new IllegalArgumentException("value cannot be null"); |
| } |
| topValue = value; |
| } |
| |
| @Override |
| public BytesRef value(int slot) { |
| return values[slot]; |
| } |
| |
| @Override |
| public int compareValues(BytesRef val1, BytesRef val2) { |
| // missing always sorts first: |
| if (val1.bytes == MISSING_BYTES) { |
| if (val2.bytes == MISSING_BYTES) { |
| return 0; |
| } |
| return -1; |
| } else if (val2.bytes == MISSING_BYTES) { |
| return 1; |
| } |
| return val1.compareTo(val2); |
| } |
| |
| @Override |
| public int compareTop(int doc) { |
| docTerms.get(doc, tempBR); |
| setMissingBytes(doc, tempBR); |
| return compareValues(topValue, tempBR); |
| } |
| |
| private void setMissingBytes(int doc, BytesRef br) { |
| if (br.length == 0) { |
| br.offset = 0; |
| if (docsWithField.get(doc) == false) { |
| br.bytes = MISSING_BYTES; |
| } else { |
| br.bytes = NON_MISSING_BYTES; |
| } |
| } |
| } |
| } |
| } |