org.apache.lucene.util
Class LongBitSet

java.lang.Object
  org.apache.lucene.util.LongBitSet

public final class LongBitSet
extends Object

BitSet of fixed length (numBits), backed by accessible (getBits()) long[], accessed with a long index. Use it only if you intend to store more than 2.1B bits, otherwise you should use FixedBitSet.

NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

Constructor Summary

LongBitSet(long numBits)

LongBitSet(long[] storedBits, long numBits)

Method Summary

void	and(LongBitSet other) this = this AND other
void	andNot(LongBitSet other) this = this AND NOT other
static int	bits2words(long numBits) returns the number of 64 bit words it would take to hold numBits
long	cardinality() Returns number of set bits.
void	clear(long index)
void	clear(long startIndex, long endIndex) Clears a range of bits.
LongBitSet	clone()
static LongBitSet	ensureCapacity(LongBitSet bits, long numBits) If the given LongBitSet is large enough to hold numBits, returns the given bits, otherwise returns a new LongBitSet which can hold the requested number of bits.
boolean	equals(Object o) returns true if both sets have the same bits set
void	flip(long startIndex, long endIndex) Flips a range of bits
boolean	get(long index)
boolean	getAndClear(long index)
boolean	getAndSet(long index)
long[]	getBits() Expert.
int	hashCode()
boolean	intersects(LongBitSet other) returns true if the sets have any elements in common
long	length() Returns the number of bits stored in this bitset.
long	nextSetBit(long index) Returns the index of the first set bit starting at the index specified.
void	or(LongBitSet other) this = this OR other
long	prevSetBit(long index) Returns the index of the last set bit before or on the index specified.
void	set(long index)
void	set(long startIndex, long endIndex) Sets a range of bits
void	xor(LongBitSet other) this = this XOR other

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LongBitSet

public LongBitSet(long numBits)

LongBitSet

public LongBitSet(long[] storedBits,
                  long numBits)

Method Detail

ensureCapacity

public static LongBitSet ensureCapacity(LongBitSet bits,
                                        long numBits)

If the given LongBitSet is large enough to hold numBits, returns the given bits, otherwise returns a new LongBitSet which can hold the requested number of bits.

NOTE: the returned bitset reuses the underlying long[] of the given bits if possible. Also, calling length() on the returned bits may return a value greater than numBits.

bits2words

public static int bits2words(long numBits)

returns the number of 64 bit words it would take to hold numBits

length

public long length()

Returns the number of bits stored in this bitset.

getBits

public long[] getBits()

Expert.

cardinality

public long cardinality()

Returns number of set bits. NOTE: this visits every long in the backing bits array, and the result is not internally cached!

get

public boolean get(long index)

set

public void set(long index)

getAndSet

public boolean getAndSet(long index)

clear

public void clear(long index)

getAndClear

public boolean getAndClear(long index)

nextSetBit

public long nextSetBit(long index)

Returns the index of the first set bit starting at the index specified. -1 is returned if there are no more set bits.

prevSetBit

public long prevSetBit(long 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.

or

public void or(LongBitSet other)

this = this OR other

xor

public void xor(LongBitSet other)

this = this XOR other

intersects

public boolean intersects(LongBitSet other)

returns true if the sets have any elements in common

and

public void and(LongBitSet other)

this = this AND other

andNot

public void andNot(LongBitSet other)

this = this AND NOT other

flip

public void flip(long startIndex,
                 long endIndex)

Flips a range of bits

Parameters:

startIndex - lower index

endIndex - one-past the last bit to flip

set

public void set(long startIndex,
                long endIndex)

Sets a range of bits

Parameters:

startIndex - lower index

endIndex - one-past the last bit to set

clear

public void clear(long startIndex,
                  long endIndex)

Clears a range of bits.

Parameters:

startIndex - lower index

endIndex - one-past the last bit to clear

clone

public LongBitSet clone()

Overrides:

clone in class Object

equals

public boolean equals(Object o)

returns true if both sets have the same bits set

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object