org.opencores.JLex
Class SparseBitSet

java.lang.Object
  |
  +--org.opencores.JLex.SparseBitSet

final class SparseBitSet

extends java.lang.Object

implements java.lang.Cloneable

A set of bits. The set automatically grows as more bits are needed.

Inner Class Summary

private static interface

SparseBitSet.BinOp

Field Summary

private static SparseBitSet.BinOp	AND
(package private) long[]	bits Array of bit-blocks; each holding BITS bits.
private static int	BITS Number of bits in a block.
private static int	BITS_M1 BITS-1, using the identity: x % BITS == x & (BITS-1)
private static int	LG_BITS log base 2 of BITS, for the identity: x/BITS == x >> LG_BITS
(package private) int[]	offs Sorted array of bit-block offsets.
private static SparseBitSet.BinOp	OR
(package private) int	size Number of blocks currently in use.
private static SparseBitSet.BinOp	XOR

Constructor Summary

SparseBitSet()
Creates an empty set.

SparseBitSet(int nbits)
Creates an empty set with the specified size.

SparseBitSet(SparseBitSet set)
Creates an empty set with the same size as the given set.

Method Summary

void	and(SparseBitSet set) Logically ANDs this bit set with the specified set of bits.
private static void	binop(SparseBitSet a, SparseBitSet b, SparseBitSet.BinOp op)
private int	bsearch(int bnum)
void	clear(int bit) Clears a bit.
void	clearAll() Clears all bits.
java.lang.Object	clone() Clones the SparseBitSet.
java.util.Enumeration	elements() Return an Enumeration of Integers which represent set bit indices in this SparseBitSet.
boolean	equals(java.lang.Object obj) Compares this object against the specified object.
static boolean	equals(SparseBitSet a, SparseBitSet b) Compares two SparseBitSets for equality.
boolean	get(int bit) Gets a bit.
int	hashCode() Gets the hashcode.
private void	insert_block(int idx, int bnum)
private boolean	isValid() Check validity.
static void	main(java.lang.String[] args) Self-test.
private void	new_block(int bnum)
private void	new_block(int idx, int bnum)
void	or(SparseBitSet set) Logically ORs this bit set with the specified set of bits.
void	set(int bit) Sets a bit.
int	size() Calculates and returns the set's size
java.lang.String	toString() Converts the SparseBitSet to a String.
void	xor(SparseBitSet set) Logically XORs this bit set with the specified set of bits.

Methods inherited from class java.lang.Object

, finalize, getClass, notify, notifyAll, registerNatives, wait, wait, wait

Field Detail

offs

int[] offs

Sorted array of bit-block offsets.

bits

long[] bits

Array of bit-blocks; each holding BITS bits.

size

int size

Number of blocks currently in use.

LG_BITS

private static final int LG_BITS

log base 2 of BITS, for the identity: x/BITS == x >> LG_BITS

BITS

private static final int BITS

Number of bits in a block.

BITS_M1

private static final int BITS_M1

BITS-1, using the identity: x % BITS == x & (BITS-1)

AND

private static final SparseBitSet.BinOp AND

OR

private static final SparseBitSet.BinOp OR

XOR

private static final SparseBitSet.BinOp XOR

Constructor Detail

SparseBitSet

public SparseBitSet()

Creates an empty set.

SparseBitSet

public SparseBitSet(int nbits)

Creates an empty set with the specified size.

Parameters:

nbits - the size of the set

SparseBitSet

public SparseBitSet(SparseBitSet set)

Creates an empty set with the same size as the given set.

Method Detail

new_block

private void new_block(int bnum)

new_block

private void new_block(int idx,
                       int bnum)

insert_block

private void insert_block(int idx,
                          int bnum)

bsearch

private int bsearch(int bnum)

set

public void set(int bit)

Sets a bit.

Parameters:

bit - the bit to be set

clear

public void clear(int bit)

Clears a bit.

Parameters:

bit - the bit to be cleared

clearAll

public void clearAll()

Clears all bits.

get

public boolean get(int bit)

Gets a bit.

Parameters:

bit - the bit to be gotten

and

public void and(SparseBitSet set)

Logically ANDs this bit set with the specified set of bits.

Parameters:

set - the bit set to be ANDed with

or

public void or(SparseBitSet set)

Logically ORs this bit set with the specified set of bits.

Parameters:

set - the bit set to be ORed with

xor

public void xor(SparseBitSet set)

Logically XORs this bit set with the specified set of bits.

Parameters:

set - the bit set to be XORed with

binop

private static final void binop(SparseBitSet a,
                                SparseBitSet b,
                                SparseBitSet.BinOp op)

hashCode

public int hashCode()

Gets the hashcode.

Overrides:

hashCode in class java.lang.Object

size

public int size()

Calculates and returns the set's size

equals

public boolean equals(java.lang.Object obj)

Compares this object against the specified object.

Parameters:

obj - the object to commpare with

Returns:

true if the objects are the same; false otherwise.

Overrides:

equals in class java.lang.Object

equals

public static boolean equals(SparseBitSet a,
                             SparseBitSet b)

Compares two SparseBitSets for equality.

Returns:

true if the objects are the same; false otherwise.

clone

public java.lang.Object clone()

Clones the SparseBitSet.

Overrides:

clone in class java.lang.Object

elements

public java.util.Enumeration elements()

Return an Enumeration of Integers which represent set bit indices in this SparseBitSet.

toString

public java.lang.String toString()

Converts the SparseBitSet to a String.

Overrides:

toString in class java.lang.Object

isValid

private boolean isValid()

Check validity.

main

public static void main(java.lang.String[] args)

Self-test.