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.IndexReader.AtomicReaderContext;
import org.apache.lucene.search.FieldCache.DocTermsIndex;
import org.apache.lucene.search.FieldCache.DocTerms;
import org.apache.lucene.search.cache.ByteValuesCreator;
import org.apache.lucene.search.cache.CachedArray;
import org.apache.lucene.search.cache.CachedArrayCreator;
import org.apache.lucene.search.cache.DoubleValuesCreator;
import org.apache.lucene.search.cache.FloatValuesCreator;
import org.apache.lucene.search.cache.IntValuesCreator;
import org.apache.lucene.search.cache.LongValuesCreator;
import org.apache.lucene.search.cache.ShortValuesCreator;
import org.apache.lucene.search.cache.CachedArray.ByteValues;
import org.apache.lucene.search.cache.CachedArray.DoubleValues;
import org.apache.lucene.search.cache.CachedArray.FloatValues;
import org.apache.lucene.search.cache.CachedArray.IntValues;
import org.apache.lucene.search.cache.CachedArray.LongValues;
import org.apache.lucene.search.cache.CachedArray.ShortValues;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.packed.Direct8;
import org.apache.lucene.util.packed.Direct16;
import org.apache.lucene.util.packed.Direct32;
import org.apache.lucene.util.packed.PackedInts;
/**
* 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 #copy} Installs a new hit into the
* priority queue. The {@link FieldValueHitQueue}
* calls this method when a new hit is competitive.
*
* <li> {@link #setNextReader(IndexReader.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 {
/**
* 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);
/**
* Compare the bottom of the queue with 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;
/**
* 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
* @throws IOException
*/
public abstract FieldComparator 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 upgraded to Comparable
*/
public abstract Comparable<?> value(int slot);
public static abstract class NumericComparator<T extends CachedArray> extends FieldComparator {
protected final CachedArrayCreator<T> creator;
protected T cached;
protected final boolean checkMissing;
protected Bits valid;
public NumericComparator( CachedArrayCreator<T> c, boolean checkMissing ) {
this.creator = c;
this.checkMissing = checkMissing;
}
protected FieldComparator setup(T cached) {
this.cached = cached;
if (checkMissing)
valid = cached.valid;
return this;
}
}
/** Parses field's values as byte (using {@link
* FieldCache#getBytes} and sorts by ascending value */
public static final class ByteComparator extends NumericComparator<ByteValues> {
private byte[] docValues;
private final byte[] values;
private final byte missingValue;
private byte bottom;
ByteComparator(int numHits, ByteValuesCreator creator, Byte missingValue ) {
super( creator, missingValue!=null );
values = new byte[numHits];
this.missingValue = checkMissing
? missingValue.byteValue() : 0;
}
@Override
public int compare(int slot1, int slot2) {
return values[slot1] - values[slot2];
}
@Override
public int compareBottom(int doc) {
byte v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
return bottom - v2;
}
@Override
public void copy(int slot, int doc) {
byte v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
values[slot] = v2;
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
setup(FieldCache.DEFAULT.getBytes(context.reader, creator.field, creator));
docValues = cached.values;
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return Byte.valueOf(values[slot]);
}
}
/** Parses field's values as double (using {@link
* FieldCache#getDoubles} and sorts by ascending value */
public static final class DoubleComparator extends NumericComparator<DoubleValues> {
private double[] docValues;
private final double[] values;
private final double missingValue;
private double bottom;
DoubleComparator(int numHits, DoubleValuesCreator creator, Double missingValue ) {
super( creator, missingValue != null );
values = new double[numHits];
this.missingValue = checkMissing
? missingValue.doubleValue() : 0;
}
@Override
public int compare(int slot1, int slot2) {
final double v1 = values[slot1];
final double v2 = values[slot2];
if (v1 > v2) {
return 1;
} else if (v1 < v2) {
return -1;
} else {
return 0;
}
}
@Override
public int compareBottom(int doc) {
double v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
if (bottom > v2) {
return 1;
} else if (bottom < v2) {
return -1;
} else {
return 0;
}
}
@Override
public void copy(int slot, int doc) {
double v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
values[slot] = v2;
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
setup(FieldCache.DEFAULT.getDoubles(context.reader, creator.field, creator));
docValues = cached.values;
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return Double.valueOf(values[slot]);
}
}
/** Parses field's values as float (using {@link
* FieldCache#getFloats} and sorts by ascending value */
public static final class FloatComparator extends NumericComparator<FloatValues> {
private float[] docValues;
private final float[] values;
private final float missingValue;
private float bottom;
FloatComparator(int numHits, FloatValuesCreator creator, Float missingValue ) {
super( creator, missingValue != null );
values = new float[numHits];
this.missingValue = checkMissing
? missingValue.floatValue() : 0;
}
@Override
public int compare(int slot1, int slot2) {
// TODO: are there sneaky non-branch ways to compute
// sign of float?
final float v1 = values[slot1];
final float v2 = values[slot2];
if (v1 > v2) {
return 1;
} else if (v1 < v2) {
return -1;
} else {
return 0;
}
}
@Override
public int compareBottom(int doc) {
// TODO: are there sneaky non-branch ways to compute sign of float?
float v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
if (bottom > v2) {
return 1;
} else if (bottom < v2) {
return -1;
} else {
return 0;
}
}
@Override
public void copy(int slot, int doc) {
float v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
values[slot] = v2;
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
setup(FieldCache.DEFAULT.getFloats(context.reader, creator.field, creator));
docValues = cached.values;
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return Float.valueOf(values[slot]);
}
}
/** Parses field's values as short (using {@link
* FieldCache#getShorts} and sorts by ascending value */
public static final class ShortComparator extends NumericComparator<ShortValues> {
private short[] docValues;
private final short[] values;
private short bottom;
private final short missingValue;
ShortComparator(int numHits, ShortValuesCreator creator, Short missingValue ) {
super( creator, missingValue != null );
values = new short[numHits];
this.missingValue = checkMissing
? missingValue.shortValue() : 0;
}
@Override
public int compare(int slot1, int slot2) {
return values[slot1] - values[slot2];
}
@Override
public int compareBottom(int doc) {
short v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
return bottom - v2;
}
@Override
public void copy(int slot, int doc) {
short v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
values[slot] = v2;
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
setup( FieldCache.DEFAULT.getShorts(context.reader, creator.field, creator));
docValues = cached.values;
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return Short.valueOf(values[slot]);
}
}
/** Parses field's values as int (using {@link
* FieldCache#getInts} and sorts by ascending value */
public static final class IntComparator extends NumericComparator<IntValues> {
private int[] docValues;
private final int[] values;
private int bottom; // Value of bottom of queue
final int missingValue;
IntComparator(int numHits, IntValuesCreator creator, Integer missingValue ) {
super( creator, missingValue != null );
values = new int[numHits];
this.missingValue = checkMissing
? missingValue.intValue() : 0;
}
@Override
public int compare(int slot1, int slot2) {
// TODO: there are sneaky non-branch ways to compute
// -1/+1/0 sign
// Cannot return values[slot1] - values[slot2] because that
// may overflow
final int v1 = values[slot1];
final int v2 = values[slot2];
if (v1 > v2) {
return 1;
} else if (v1 < v2) {
return -1;
} else {
return 0;
}
}
@Override
public int compareBottom(int doc) {
// TODO: there are sneaky non-branch ways to compute
// -1/+1/0 sign
// Cannot return bottom - values[slot2] because that
// may overflow
int v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
if (bottom > v2) {
return 1;
} else if (bottom < v2) {
return -1;
} else {
return 0;
}
}
@Override
public void copy(int slot, int doc) {
int v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
values[slot] = v2;
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
setup(FieldCache.DEFAULT.getInts(context.reader, creator.field, creator));
docValues = cached.values;
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return Integer.valueOf(values[slot]);
}
}
/** Parses field's values as long (using {@link
* FieldCache#getLongs} and sorts by ascending value */
public static final class LongComparator extends NumericComparator<LongValues> {
private long[] docValues;
private final long[] values;
private long bottom;
private final long missingValue;
LongComparator(int numHits, LongValuesCreator creator, Long missingValue ) {
super( creator, missingValue != null );
values = new long[numHits];
this.missingValue = checkMissing
? missingValue.longValue() : 0;
}
@Override
public int compare(int slot1, int slot2) {
// TODO: there are sneaky non-branch ways to compute
// -1/+1/0 sign
final long v1 = values[slot1];
final long v2 = values[slot2];
if (v1 > v2) {
return 1;
} else if (v1 < v2) {
return -1;
} else {
return 0;
}
}
@Override
public int compareBottom(int doc) {
// TODO: there are sneaky non-branch ways to compute
// -1/+1/0 sign
long v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
if (bottom > v2) {
return 1;
} else if (bottom < v2) {
return -1;
} else {
return 0;
}
}
@Override
public void copy(int slot, int doc) {
long v2 = docValues[doc];
if (valid != null && v2==0 && !valid.get(doc))
v2 = missingValue;
values[slot] = v2;
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
setup(FieldCache.DEFAULT.getLongs(context.reader, creator.field, creator));
docValues = cached.values;
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return Long.valueOf(values[slot]);
}
}
/** 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 {
private final float[] scores;
private float bottom;
private Scorer scorer;
RelevanceComparator(int numHits) {
scores = new float[numHits];
}
@Override
public int compare(int slot1, int slot2) {
final float score1 = scores[slot1];
final float score2 = scores[slot2];
return score1 > score2 ? -1 : (score1 < score2 ? 1 : 0);
}
@Override
public int compareBottom(int doc) throws IOException {
float score = scorer.score();
return bottom > score ? -1 : (bottom < score ? 1 : 0);
}
@Override
public void copy(int slot, int doc) throws IOException {
scores[slot] = scorer.score();
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) {
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = scores[bottom];
}
@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.
this.scorer = new ScoreCachingWrappingScorer(scorer);
}
@Override
public Comparable<?> value(int slot) {
return Float.valueOf(scores[slot]);
}
}
/** Sorts by ascending docID */
public static final class DocComparator extends FieldComparator {
private final int[] docIDs;
private int docBase;
private int bottom;
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 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 Comparable<?> value(int slot) {
return Integer.valueOf(docIDs[slot]);
}
}
/** Sorts by field's natural Term sort order, using
* ordinals. This is functionally equivalent to {@link
* 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 TermValComparator}. For very small
* result sets it may be slower. */
public static final class TermOrdValComparator extends FieldComparator {
/** @lucene.internal */
final int[] ords;
/** @lucene.internal */
final BytesRef[] values;
/** @lucene.internal */
final int[] readerGen;
/** @lucene.internal */
int currentReaderGen = -1;
private DocTermsIndex termsIndex;
private final String field;
/** @lucene.internal */
int bottomSlot = -1;
/** @lucene.internal */
int bottomOrd;
/** @lucene.internal */
boolean bottomSameReader;
/** @lucene.internal */
BytesRef bottomValue;
/** @lucene.internal */
final BytesRef tempBR = new BytesRef();
public TermOrdValComparator(int numHits, String field, int sortPos, boolean reversed) {
ords = new int[numHits];
values = new BytesRef[numHits];
readerGen = new int[numHits];
this.field = field;
}
@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 -1;
} else if (val2 == null) {
return 1;
}
return val1.compareTo(val2);
}
@Override
public int compareBottom(int doc) {
throw new UnsupportedOperationException();
}
@Override
public void copy(int slot, int doc) {
throw new UnsupportedOperationException();
}
/** Base class for specialized (per bit width of the
* ords) per-segment comparator. NOTE: this is messy;
* we do this only because hotspot can't reliably inline
* the underlying array access when looking up doc->ord
* @lucene.internal
*/
abstract class PerSegmentComparator extends FieldComparator {
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
return TermOrdValComparator.this.setNextReader(context);
}
@Override
public int compare(int slot1, int slot2) {
return TermOrdValComparator.this.compare(slot1, slot2);
}
@Override
public void setBottom(final int bottom) {
TermOrdValComparator.this.setBottom(bottom);
}
@Override
public Comparable<?> value(int slot) {
return TermOrdValComparator.this.value(slot);
}
}
// Used per-segment when bit width of doc->ord is 8:
private final class ByteOrdComparator extends PerSegmentComparator {
private final byte[] readerOrds;
private final DocTermsIndex termsIndex;
private final int docBase;
public ByteOrdComparator(byte[] readerOrds, DocTermsIndex termsIndex, int docBase) {
this.readerOrds = readerOrds;
this.termsIndex = termsIndex;
this.docBase = docBase;
}
@Override
public int compareBottom(int doc) {
assert bottomSlot != -1;
if (bottomSameReader) {
// ord is precisely comparable, even in the equal case
return bottomOrd - (readerOrds[doc]&0xFF);
} else {
// ord is only approx comparable: if they are not
// equal, we can use that; if they are equal, we
// must fallback to compare by value
final int order = readerOrds[doc]&0xFF;
final int cmp = bottomOrd - order;
if (cmp != 0) {
return cmp;
}
if (bottomValue == null) {
if (order == 0) {
// unset
return 0;
}
// bottom wins
return -1;
} else if (order == 0) {
// doc wins
return 1;
}
termsIndex.lookup(order, tempBR);
return bottomValue.compareTo(tempBR);
}
}
@Override
public void copy(int slot, int doc) {
final int ord = readerOrds[doc]&0xFF;
ords[slot] = ord;
if (ord == 0) {
values[slot] = null;
} else {
assert ord > 0;
if (values[slot] == null) {
values[slot] = new BytesRef();
}
termsIndex.lookup(ord, values[slot]);
}
readerGen[slot] = currentReaderGen;
}
}
// Used per-segment when bit width of doc->ord is 16:
private final class ShortOrdComparator extends PerSegmentComparator {
private final short[] readerOrds;
private final DocTermsIndex termsIndex;
private final int docBase;
public ShortOrdComparator(short[] readerOrds, DocTermsIndex termsIndex, int docBase) {
this.readerOrds = readerOrds;
this.termsIndex = termsIndex;
this.docBase = docBase;
}
@Override
public int compareBottom(int doc) {
assert bottomSlot != -1;
if (bottomSameReader) {
// ord is precisely comparable, even in the equal case
return bottomOrd - (readerOrds[doc]&0xFFFF);
} else {
// ord is only approx comparable: if they are not
// equal, we can use that; if they are equal, we
// must fallback to compare by value
final int order = readerOrds[doc]&0xFFFF;
final int cmp = bottomOrd - order;
if (cmp != 0) {
return cmp;
}
if (bottomValue == null) {
if (order == 0) {
// unset
return 0;
}
// bottom wins
return -1;
} else if (order == 0) {
// doc wins
return 1;
}
termsIndex.lookup(order, tempBR);
return bottomValue.compareTo(tempBR);
}
}
@Override
public void copy(int slot, int doc) {
final int ord = readerOrds[doc]&0xFFFF;
ords[slot] = ord;
if (ord == 0) {
values[slot] = null;
} else {
assert ord > 0;
if (values[slot] == null) {
values[slot] = new BytesRef();
}
termsIndex.lookup(ord, values[slot]);
}
readerGen[slot] = currentReaderGen;
}
}
// Used per-segment when bit width of doc->ord is 32:
private final class IntOrdComparator extends PerSegmentComparator {
private final int[] readerOrds;
private final DocTermsIndex termsIndex;
private final int docBase;
public IntOrdComparator(int[] readerOrds, DocTermsIndex termsIndex, int docBase) {
this.readerOrds = readerOrds;
this.termsIndex = termsIndex;
this.docBase = docBase;
}
@Override
public int compareBottom(int doc) {
assert bottomSlot != -1;
if (bottomSameReader) {
// ord is precisely comparable, even in the equal case
return bottomOrd - readerOrds[doc];
} else {
// ord is only approx comparable: if they are not
// equal, we can use that; if they are equal, we
// must fallback to compare by value
final int order = readerOrds[doc];
final int cmp = bottomOrd - order;
if (cmp != 0) {
return cmp;
}
if (bottomValue == null) {
if (order == 0) {
// unset
return 0;
}
// bottom wins
return -1;
} else if (order == 0) {
// doc wins
return 1;
}
termsIndex.lookup(order, tempBR);
return bottomValue.compareTo(tempBR);
}
}
@Override
public void copy(int slot, int doc) {
final int ord = readerOrds[doc];
ords[slot] = ord;
if (ord == 0) {
values[slot] = null;
} else {
assert ord > 0;
if (values[slot] == null) {
values[slot] = new BytesRef();
}
termsIndex.lookup(ord, values[slot]);
}
readerGen[slot] = currentReaderGen;
}
}
// Used per-segment when bit width is not a native array
// size (8, 16, 32):
private final class AnyOrdComparator extends PerSegmentComparator {
private final PackedInts.Reader readerOrds;
private final DocTermsIndex termsIndex;
private final int docBase;
public AnyOrdComparator(PackedInts.Reader readerOrds, DocTermsIndex termsIndex, int docBase) {
this.readerOrds = readerOrds;
this.termsIndex = termsIndex;
this.docBase = docBase;
}
@Override
public int compareBottom(int doc) {
assert bottomSlot != -1;
if (bottomSameReader) {
// ord is precisely comparable, even in the equal case
return bottomOrd - (int) readerOrds.get(doc);
} else {
// ord is only approx comparable: if they are not
// equal, we can use that; if they are equal, we
// must fallback to compare by value
final int order = (int) readerOrds.get(doc);
final int cmp = bottomOrd - order;
if (cmp != 0) {
return cmp;
}
if (bottomValue == null) {
if (order == 0) {
// unset
return 0;
}
// bottom wins
return -1;
} else if (order == 0) {
// doc wins
return 1;
}
termsIndex.lookup(order, tempBR);
return bottomValue.compareTo(tempBR);
}
}
@Override
public void copy(int slot, int doc) {
final int ord = (int) readerOrds.get(doc);
ords[slot] = ord;
if (ord == 0) {
values[slot] = null;
} else {
assert ord > 0;
if (values[slot] == null) {
values[slot] = new BytesRef();
}
termsIndex.lookup(ord, values[slot]);
}
readerGen[slot] = currentReaderGen;
}
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
final int docBase = context.docBase;
termsIndex = FieldCache.DEFAULT.getTermsIndex(context.reader, field);
final PackedInts.Reader docToOrd = termsIndex.getDocToOrd();
FieldComparator perSegComp;
if (docToOrd instanceof Direct8) {
perSegComp = new ByteOrdComparator(((Direct8) docToOrd).getArray(), termsIndex, docBase);
} else if (docToOrd instanceof Direct16) {
perSegComp = new ShortOrdComparator(((Direct16) docToOrd).getArray(), termsIndex, docBase);
} else if (docToOrd instanceof Direct32) {
perSegComp = new IntOrdComparator(((Direct32) docToOrd).getArray(), termsIndex, docBase);
} else {
perSegComp = new AnyOrdComparator(docToOrd, termsIndex, docBase);
}
currentReaderGen++;
if (bottomSlot != -1) {
perSegComp.setBottom(bottomSlot);
}
return perSegComp;
}
@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) {
// 0 ord is null for all segments
assert ords[bottomSlot] == 0;
bottomOrd = 0;
bottomSameReader = true;
readerGen[bottomSlot] = currentReaderGen;
} else {
final int index = binarySearch(tempBR, termsIndex, bottomValue);
if (index < 0) {
bottomOrd = -index - 2;
bottomSameReader = false;
} else {
bottomOrd = index;
// exact value match
bottomSameReader = true;
readerGen[bottomSlot] = currentReaderGen;
ords[bottomSlot] = bottomOrd;
}
}
}
}
@Override
public Comparable<?> value(int slot) {
return values[slot];
}
}
/** 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. */
public static final class TermValComparator extends FieldComparator {
private BytesRef[] values;
private DocTerms docTerms;
private final String field;
private BytesRef bottom;
private final BytesRef tempBR = new BytesRef();
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 == null) {
if (val2 == null) {
return 0;
}
return -1;
} else if (val2 == null) {
return 1;
}
return val1.compareTo(val2);
}
@Override
public int compareBottom(int doc) {
BytesRef val2 = docTerms.getTerm(doc, tempBR);
if (bottom == null) {
if (val2 == null) {
return 0;
}
return -1;
} else if (val2 == null) {
return 1;
}
return bottom.compareTo(val2);
}
@Override
public void copy(int slot, int doc) {
if (values[slot] == null) {
values[slot] = new BytesRef();
}
docTerms.getTerm(doc, values[slot]);
}
@Override
public FieldComparator setNextReader(AtomicReaderContext context) throws IOException {
docTerms = FieldCache.DEFAULT.getTerms(context.reader, field);
return this;
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable<?> value(int slot) {
return values[slot];
}
}
final protected static int binarySearch(BytesRef br, DocTermsIndex a, BytesRef key) {
return binarySearch(br, a, key, 1, a.numOrd()-1);
}
final protected static int binarySearch(BytesRef br, DocTermsIndex a, BytesRef key, int low, int high) {
while (low <= high) {
int mid = (low + high) >>> 1;
BytesRef midVal = a.lookup(mid, br);
int cmp;
if (midVal != null) {
cmp = midVal.compareTo(key);
} else {
cmp = -1;
}
if (cmp < 0)
low = mid + 1;
else if (cmp > 0)
high = mid - 1;
else
return mid;
}
return -(low + 1);
}
}