org.apache.jena.atlas.lib
Class BitsLong

java.lang.Object
  org.apache.jena.atlas.lib.BitsLong

public final class BitsLong
extends Object

Utilities for manipulating a bit pattern which are held in a 64 bit long

See Also:

(java.util.BitSet does not allow getting the pattern as a long)

Method Summary

static long	access(long bits, int start, int finish) Get the bits from start (inclusive) to finish (exclusive), leaving them aligned in the long.
static long	clear(long bits, int start, int finish) Clear the bits specified.
static boolean	isSet(long bits, int bitIndex) Test whether a bit is set
static long	mask(int start, int finish) Create a mask that has ones between bit positions start (inc) and finish (exc), and zeros elsewhere.
static long	maskZero(int start, int finish) Create a mask that has zeros between bit positions start (inc) and finish (exc), and ones elsewhere
static long	pack(long bits, long value, int start, int finish) Place the value into the bit pattern between start and finish and returns the new value.
static long	set(long bits, int bitIndex) Set the bits specificied.
static long	set(long bits, int start, int finish) Set the bits from string (inc) to finish (exc) to one
static boolean	test(long bits, boolean isSet, int bitIndex) Test whether a bit is the same as isSet
static boolean	test(long bits, long value, int start, int finish) Test whether a range has a specific value or not
static long	unpack(long bits, int start, int finish) Extract the value packed into bits start (inclusive) and finish (exclusive), the value is returned the low part of the returned long.
static long	unpack(String str, int startChar, int finishChar) Get bits from a hex string.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

unpack

public static final long unpack(long bits,
                                int start,
                                int finish)

Extract the value packed into bits start (inclusive) and finish (exclusive), the value is returned the low part of the returned long. The low bit is bit zero.

Parameters:

bits -

start -

finish -

Returns:

long

pack

public static final long pack(long bits,
                              long value,
                              int start,
                              int finish)

Place the value into the bit pattern between start and finish and returns the new value. Leaves other bits alone.

Parameters:

bits -

value -

start -

finish -

Returns:

long

unpack

public static final long unpack(String str,
                                int startChar,
                                int finishChar)

Get bits from a hex string.

Parameters:

str -

startChar - Index of first character (counted from the left, string style).

finishChar - Index after the last character (counted from the left, string style).

Returns:

long

set

public static final long set(long bits,
                             int bitIndex)

Set the bits specificied.

Parameters:

bits - Pattern

bitIndex -

Returns:

Modified pattern

set

public static final long set(long bits,
                             int start,
                             int finish)

Set the bits from string (inc) to finish (exc) to one

Parameters:

bits - Pattern

start - start (inclusive)

finish - finish (exclusive)

Returns:

Modified pattern

test

public static final boolean test(long bits,
                                 boolean isSet,
                                 int bitIndex)

Test whether a bit is the same as isSet

Parameters:

bits - Pattern

isSet - Test whether is set or not.

bitIndex - Bit index

Returns:

Boolean

isSet

public static final boolean isSet(long bits,
                                  int bitIndex)

Test whether a bit is set

Parameters:

bits - Pattern

bitIndex - Bit index

Returns:

Boolean

test

public static final boolean test(long bits,
                                 long value,
                                 int start,
                                 int finish)

Test whether a range has a specific value or not

Parameters:

bits - Pattern

value - Value to test for

start - start (inclusive)

finish - finish (exclusive)

Returns:

Boolean

access

public static final long access(long bits,
                                int start,
                                int finish)

Get the bits from start (inclusive) to finish (exclusive), leaving them aligned in the long. See also unpack, returns the value found at that place.

Parameters:

bits -

start -

finish -

Returns:

lon

See Also:

unpack(long, int, int)

clear

public static final long clear(long bits,
                               int start,
                               int finish)

Clear the bits specified.

Parameters:

bits -

start -

finish -

Returns:

long

mask

public static final long mask(int start,
                              int finish)

Create a mask that has ones between bit positions start (inc) and finish (exc), and zeros elsewhere.

Parameters:

start -

finish -

Returns:

long

maskZero

public static final long maskZero(int start,
                                  int finish)

Create a mask that has zeros between bit positions start (inc) and finish (exc), and ones elsewhere

Parameters:

start -

finish -

Returns:

long