Package org.teiid.common.buffer.impl

Class ConcurrentBitSet

java.lang.Object

org.teiid.common.buffer.impl.ConcurrentBitSet

public class ConcurrentBitSet
extends Object

A segmented BitSet that supports greater concurrency and faster finding of clear bits.

Constructor Summary

Constructors

Constructor	Description
ConcurrentBitSet(int maxBits, int concurrencyLevel)

Method Summary

Modifier and Type	Method	Description
void	clear(int bitIndex)
int	compactHighestBitSet(int segment)
int	getAndSetNextClearBit()	Makes a best effort to atomically find the next clear bit and set it
int	getAndSetNextClearBit(int segment)
int	getBitsPerSegment()
int	getBitsSet()
int	getBitsSet(int segment)	return an estimate of the number of bits set
int	getHighestBitSet(int segment)	return an estimate of the highest bit (relative index) that has been set
int	getNextSegment()
int	getTotalBits()
void	setCompact(boolean compact)	Set to always allocate against the first available block in a segment.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ConcurrentBitSet

public ConcurrentBitSet(int maxBits,
                        int concurrencyLevel)

Parameters:

maxBits -

concurrencyLevel - - should be a power of 2

Method Detail

clear

public void clear(int bitIndex)

getAndSetNextClearBit

public int getAndSetNextClearBit()

Makes a best effort to atomically find the next clear bit and set it

Returns:

the next bit index or -1 if no clear bits are found

getNextSegment

public int getNextSegment()

getBitsSet

public int getBitsSet(int segment)

return an estimate of the number of bits set

Parameters:

segment -

Returns:

getHighestBitSet

public int getHighestBitSet(int segment)

return an estimate of the highest bit (relative index) that has been set

Parameters:

segment -

Returns:

getAndSetNextClearBit

public int getAndSetNextClearBit(int segment)

Parameters:

segment -

Returns:

the next clear bit index as an absolute index - not relative to a segment

getTotalBits

public int getTotalBits()

getBitsSet

public int getBitsSet()

getBitsPerSegment

public int getBitsPerSegment()

setCompact

public void setCompact(boolean compact)

Set to always allocate against the first available block in a segment.

Parameters:

compact -

compactHighestBitSet

public int compactHighestBitSet(int segment)

toString

public String toString()

Overrides:

toString in class Object