Java Reference
In-Depth Information
22.2.
BitSet
The
BitSet
class provides a way to create a bit vector that grows dynam-
ically. In effect, a bit set is a vector of
TRue
or
false
bits indexed from
0
to
Integer.MAX_VALUE,
all of them initially
false
. These bits can be individually
set, cleared, or retrieved.
BitSet
uses only sufficient storage to hold the
highest index bit that has been setany bits beyond that are deemed to
be
false
.
Methods that take indices into the set throw
IndexOutOfBoundsException
if a
supplied index is negative or, where relevant, if the
from
index is greater
than the
to
index.
There are two constructors for
BitSet
:
public
BitSet(int size)
Creates a new bit set with enough initial storage to explicitly
represent bits indexed from
0
to
size-1
. All bits are initially
false
.
public
BitSet()
Creates a new bit set with a default amount of initial storage.
All bits are initially
false
.
There are four methods for dealing with individual bits.
public void
set(int index)
Sets the bit specified by
index
to
TRue.
public void
clear(int index)
Sets the bit specified by
index
to
false
.
