Package org.apache.lucene.util
Class BitSet
- java.lang.Object
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- org.apache.lucene.util.BitSet
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- All Implemented Interfaces:
Accountable,Bits
- Direct Known Subclasses:
FixedBitSet,SparseFixedBitSet
public abstract class BitSet extends Object implements Bits, Accountable
Base implementation for a bit set.- NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.
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Nested Class Summary
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Nested classes/interfaces inherited from interface org.apache.lucene.util.Bits
Bits.MatchAllBits, Bits.MatchNoBits
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Field Summary
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Fields inherited from interface org.apache.lucene.util.Accountable
NULL_ACCOUNTABLE
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Fields inherited from interface org.apache.lucene.util.Bits
EMPTY_ARRAY
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Constructor Summary
Constructors Constructor Description BitSet()
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Method Summary
All Methods Static Methods Instance Methods Abstract Methods Concrete Methods Modifier and Type Method Description abstract intapproximateCardinality()Return an approximation of the cardinality of this set.abstract intcardinality()Return the number of bits that are set.protected voidcheckUnpositioned(DocIdSetIterator iter)Assert that the current doc is -1.voidclear()Clear all the bits of the set.abstract voidclear(int i)Clear the bit ati.abstract voidclear(int startIndex, int endIndex)Clears a range of bits.abstract booleangetAndSet(int i)Set the bit ati, returningtrueif it was previously set.intnextSetBit(int index)Returns the index of the first set bit starting at the index specified.abstract intnextSetBit(int start, int end)Returns the index of the first set bit from start (inclusive) until end (exclusive).static BitSetof(DocIdSetIterator it, int maxDoc)Build aBitSetfrom the content of the providedDocIdSetIterator.voidor(DocIdSetIterator iter)Does in-place OR of the bits provided by the iterator.abstract intprevSetBit(int index)Returns the index of the last set bit before or on the index specified.abstract voidset(int i)Set the bit ati.-
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
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Methods inherited from interface org.apache.lucene.util.Accountable
getChildResources, ramBytesUsed
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Method Detail
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of
public static BitSet of(DocIdSetIterator it, int maxDoc) throws IOException
Build aBitSetfrom the content of the providedDocIdSetIterator. NOTE: this will fully consume theDocIdSetIterator.- Throws:
IOException
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clear
public void clear()
Clear all the bits of the set.Depending on the implementation, this may be significantly faster than clear(0, length).
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set
public abstract void set(int i)
Set the bit ati.
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getAndSet
public abstract boolean getAndSet(int i)
Set the bit ati, returningtrueif it was previously set.
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clear
public abstract void clear(int i)
Clear the bit ati.
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clear
public abstract void clear(int startIndex, int endIndex)Clears a range of bits.- Parameters:
startIndex- lower indexendIndex- one-past the last bit to clear
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cardinality
public abstract int cardinality()
Return the number of bits that are set. NOTE: this method is likely to run in linear time
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approximateCardinality
public abstract int approximateCardinality()
Return an approximation of the cardinality of this set. Some implementations may trade accuracy for speed if they have the ability to estimate the cardinality of the set without iterating over all the data. The default implementation returnscardinality().
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prevSetBit
public abstract int prevSetBit(int index)
Returns the index of the last set bit before or on the index specified. -1 is returned if there are no more set bits.
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nextSetBit
public int nextSetBit(int index)
Returns the index of the first set bit starting at the index specified.DocIdSetIterator.NO_MORE_DOCSis returned if there are no more set bits.
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nextSetBit
public abstract int nextSetBit(int start, int end)Returns the index of the first set bit from start (inclusive) until end (exclusive).DocIdSetIterator.NO_MORE_DOCSis returned if there are no more set bits.
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checkUnpositioned
protected final void checkUnpositioned(DocIdSetIterator iter)
Assert that the current doc is -1.
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or
public void or(DocIdSetIterator iter) throws IOException
Does in-place OR of the bits provided by the iterator. The state of the iterator after this operation terminates is undefined.- Throws:
IOException
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