Java Reference
In-Depth Information
Comparison of
Float
and
Double
objects behaves differently than
float
and
double
values. Each wrapper class defines a sorting order that treats
0 less than +0, NaNs greater than all values (including +
), and all
NaNs equal to each other.
When converting to a string, NaN values return the string
"NaN"
, + re-
turns
"Infinity"
and - returns
"-Infinity"
. The string-taking construct-
or, and the
parse
Type
method are defined in terms of the
valueOf
method,
which accepts strings in the following form:
•
The values
"NaN"
or
"Infinity"
with an optional leading
+
or
-
char-
acter
•
A floating-point literal
•
A hexadecimal floating-point literal
In contrast to the integer wrapper classes, the string is first stripped
of leading and trailing whitespace. If the literal forms contain a trailing
float or double specifier, such as
"1.0f"
, the specifier is ignored and the
string is converted directly to a value of the requested type.
To let you manipulate the bits inside a floating-point value's represent-
ation,
Float
provides methods to get the bit pattern as an
int
, as well as
a way to convert a bit pattern in an
int
to a
float
value (according to the
appropriate
IEEE
754 floating-point bit layout). The
Double
class provides
equivalent methods to turn a
double
value into a
long
bit pattern and vice
versa:
public static int
floatToIntBits(float val)
Returns the bit representation of the
float
value as an
int
. All
NaN values are always represented by the same bit pattern.
public static int
floatToRawIntBits(float val)
