Module org.apache.lucene.core
Class DocComparator.DocLeafComparator
java.lang.Object
org.apache.lucene.search.comparators.DocComparator.DocLeafComparator
- All Implemented Interfaces:
LeafFieldComparator
- Enclosing class:
- DocComparator
DocLeafComparator with skipping functionality. When sort by _doc asc, after collecting top N
matches and enough hits, the comparator can skip all the following documents. When sort by _doc
asc and "top" document is set after which search should start, the comparator provides an
iterator that can quickly skip to the desired "top" document.
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate DocIdSetIterator
private final int
private final int
private final int
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionint
compareBottom
(int doc) Compare the bottom of the queue with this doc.int
compareTop
(int doc) Compare the top value with this doc.Returns a competitive iteratorvoid
copy
(int slot, int doc) This method is called when a new hit is competitive.void
setBottom
(int slot) Set the bottom slot, ie the "weakest" (sorted last) entry in the queue.void
Informs this leaf comparator that hits threshold is reached.void
Sets the Scorer to use in case a document's score is needed.private void
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Field Details
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docBase
private final int docBase -
minDoc
private final int minDoc -
maxDoc
private final int maxDoc -
competitiveIterator
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Constructor Details
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DocLeafComparator
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Method Details
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setBottom
public void setBottom(int slot) Description copied from interface:LeafFieldComparator
Set the bottom slot, ie the "weakest" (sorted last) entry in the queue. WhenLeafFieldComparator.compareBottom(int)
is called, you should compare against this slot. This will always be called beforeLeafFieldComparator.compareBottom(int)
.- Specified by:
setBottom
in interfaceLeafFieldComparator
- Parameters:
slot
- the currently weakest (sorted last) slot in the queue
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compareBottom
public int compareBottom(int doc) Description copied from interface:LeafFieldComparator
Compare the bottom of the queue with this doc. This will only invoked after setBottom has been called. This should return the same result asFieldComparator.compare(int,int)
} as if bottom were slot1 and the new document were slot 2.For a search that hits many results, this method will be the hotspot (invoked by far the most frequently).
- Specified by:
compareBottom
in interfaceLeafFieldComparator
- Parameters:
doc
- that was hit- Returns:
- any
N < 0
if the doc's value is sorted after the bottom entry (not competitive), anyN > 0
if the doc's value is sorted before the bottom entry and0
if they are equal.
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compareTop
public int compareTop(int doc) Description copied from interface:LeafFieldComparator
Compare the top value with this doc. This will only invoked after setTopValue has been called. This should return the same result asFieldComparator.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).- Specified by:
compareTop
in interfaceLeafFieldComparator
- Parameters:
doc
- that was hit- Returns:
- any
N < 0
if the doc's value is sorted after the top entry (not competitive), anyN > 0
if the doc's value is sorted before the top entry and0
if they are equal.
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copy
Description copied from interface:LeafFieldComparator
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.- Specified by:
copy
in interfaceLeafFieldComparator
- Parameters:
slot
- which slot to copy the hit todoc
- docID relative to current reader- Throws:
IOException
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setScorer
Description copied from interface:LeafFieldComparator
Sets the Scorer to use in case a document's score is needed.- Specified by:
setScorer
in interfaceLeafFieldComparator
- Parameters:
scorer
- Scorer instance that you should use to obtain the current hit's score, if necessary.- Throws:
IOException
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competitiveIterator
Description copied from interface:LeafFieldComparator
Returns a competitive iterator- Specified by:
competitiveIterator
in interfaceLeafFieldComparator
- Returns:
- an iterator over competitive docs that are stronger than already collected docs or
null
if such an iterator is not available for the current comparator or segment.
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setHitsThresholdReached
public void setHitsThresholdReached()Description copied from interface:LeafFieldComparator
Informs this leaf comparator that hits threshold is reached. This method is called from a collector when hits threshold is reached.- Specified by:
setHitsThresholdReached
in interfaceLeafFieldComparator
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updateIterator
private void updateIterator()
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