de.caff.util

Class BitMask32

java.lang.Object

de.caff.util.BitMask32

All Implemented Interfaces:

BitMask

public final class BitMask32
extends java.lang.Object
implements BitMask

A bit mask for 32 bit flags.

Please note that this class will not handle more than 32 bits. Setting any higher bits will have no result.

This class is immutable.

Author:

Rammi

Field Summary

Fields

Modifier and Type	Field and Description
static BitMask32	ALL_SET The bit mask where all 32 bits are set.
static int	BIT_COUNT The number of bits in this class.
static BitMask32	ZERO The zero bit mask.

Constructor Summary

Constructors

Constructor and Description
BitMask32(int flags) Constructor.

Method Summary

Modifier and Type	Method and Description
BitMask	and(BitMask other) Get the result of a logical and of this bit mask and another.
BitMask	andNot(BitMask other) Get the result of a logical and of this bit mask and the inverse of another.
BitMask	clear(int pos) Clear the flag at the given position.
BitMask	cleared() Get a bit mask from this where all flags are cleared.
boolean	equals(java.lang.Object o)
BitMask	flip(int pos) Flip the flag at the given position.
int	getBitCount() Get the number of possible bits used in this flag.
int	getCardinality() Get the number of bits set in this flag.
int	getHighestBitSet() Get the position of the highest bit set.
int	getLowestBitSet() Get the position of the lowest bit set.
int	hashCode()
boolean	isEmpty() Is no flag set?
boolean	isSet(int pos) Is the flag at the given position set?
int	low32() Get the lower 32 bits of this mask.
long	low64() Get the lower 64 bits of this mask.
BitMask	not() Get the inverse of this bit mask.
BitMask	or(BitMask other) Get the result of a logical or of this bit mask and another.
BitMask	set(int pos) Set the flag at the given position.
java.util.BitSet	toBitSet() Convert this bit mask into a bit set.
java.lang.String	toString() Returns a string representation of the object.
BitMask	xor(BitMask other) Get the result of a logical xor (exclusive or) of this bit mask and another.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

BIT_COUNT

public static final int BIT_COUNT

The number of bits in this class.

See Also:

Constant Field Values

ZERO

public static final BitMask32 ZERO

The zero bit mask. This has all 32 flags unset.

ALL_SET

public static final BitMask32 ALL_SET

The bit mask where all 32 bits are set.

Constructor Detail

BitMask32

public BitMask32(int flags)

Constructor.

Parameters:

flags - bit mask, only the 16 low order bits are used

Method Detail

isSet

public boolean isSet(int pos)

Is the flag at the given position set?

Specified by:

isSet in interface BitMask

Parameters:

pos - position (non-negative)

Returns:

true: the flag is set
false: the flag is not set

getBitCount

public int getBitCount()

Get the number of possible bits used in this flag.

Specified by:

getBitCount in interface BitMask

Returns:

bit count

getCardinality

public int getCardinality()

Get the number of bits set in this flag.

Specified by:

getCardinality in interface BitMask

Returns:

set bit count

isEmpty

public boolean isEmpty()

Is no flag set?

Specified by:

isEmpty in interface BitMask

Returns:

true: if no flag in this bit mask is set
false: if any flag in this bit mask is set

set

@NotNull
public BitMask set(int pos)

Set the flag at the given position.

Specified by:

set in interface BitMask

Parameters:

pos - position (non-negative)

Returns:

bit mask where the flag at the given position is set

clear

@NotNull
public BitMask clear(int pos)

Clear the flag at the given position.

Specified by:

clear in interface BitMask

Parameters:

pos - position

Returns:

bit mask where the flag at the given position is cleared

flip

@NotNull
public BitMask flip(int pos)

Flip the flag at the given position.

Specified by:

flip in interface BitMask

Parameters:

pos - position

Returns:

bit mask where the flag at the given position is flipped

not

@NotNull
public BitMask not()

Get the inverse of this bit mask.

Specified by:

not in interface BitMask

Returns:

inverse bit mask

and

@NotNull
public BitMask and(@NotNull
                            BitMask other)

Get the result of a logical and of this bit mask and another.

Specified by:

and in interface BitMask

Parameters:

other - other bit mask

Returns:

resulting bit mask

andNot

@NotNull
public BitMask andNot(@NotNull
                               BitMask other)

Get the result of a logical and of this bit mask and the inverse of another.

Specified by:

andNot in interface BitMask

Parameters:

other - other bit mask

Returns:

resulting bit mask

or

@NotNull
public BitMask or(@NotNull
                           BitMask other)

Get the result of a logical or of this bit mask and another.

Specified by:

or in interface BitMask

Parameters:

other - other bit mask

Returns:

resulting bit mask

xor

@NotNull
public BitMask xor(@NotNull
                            BitMask other)

Get the result of a logical xor (exclusive or) of this bit mask and another.

Specified by:

xor in interface BitMask

Parameters:

other - other bit mask

Returns:

resulting bit mask

toBitSet

@NotNull
public java.util.BitSet toBitSet()

Convert this bit mask into a bit set.

Specified by:

toBitSet in interface BitMask

Returns:

bit set

low32

public int low32()

Get the lower 32 bits of this mask.

Specified by:

low32 in interface BitMask

Returns:

lower 32 bits as an int

low64

public long low64()

Get the lower 64 bits of this mask.

Specified by:

low64 in interface BitMask

Returns:

lower 64 bits

getLowestBitSet

public int getLowestBitSet()

Description copied from interface: BitMask

Get the position of the lowest bit set.

Specified by:

getLowestBitSet in interface BitMask

Returns:

position of the lowest bit set, or -1 if no bit is set

getHighestBitSet

public int getHighestBitSet()

Description copied from interface: BitMask

Get the position of the highest bit set.

Specified by:

getHighestBitSet in interface BitMask

Returns:

position of the highest bit set, or -1 if no bit is set

cleared

@NotNull
public BitMask cleared()

Description copied from interface: BitMask

Get a bit mask from this where all flags are cleared.

Specified by:

cleared in interface BitMask

Returns:

a bit mask of this type where all flags are cleared

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:

 getClass().getName() + '@' + Integer.toHexString(hashCode())
 

Overrides:

toString in class java.lang.Object

Returns:

a string representation of the object.