Java Reference
In-Depth Information
types. The
short
type creates a short integer. Variables of type
short
are appropriate when
you don't need the larger range offered by
int
.
Ask the Expert
Q
:
You say that there are four integer types:
int, short, long,
and
byte.
However, I
have heard that
char
can also be categorized as an integer type in Java. Can you
explain?
A
:
The formal specification for Java defines a type category called integral types, which
includes
byte
,
short
,
int
,
long
, and
char
. They are called integral types because they
all hold whole-number, binary values. However, the purpose of the first four is to
represent numeric integer quantities. The purpose of
char
is to represent characters.
Therefore, the principal uses of
char
and the principal uses of the other integral types
are fundamentally different. Because of the differences, the
char
type is treated sep-
arately in this topic.
Floating-Point Types
tional components. There are two kinds of floating-point types,
float
and
double
, which
represent single- and double-precision numbers, respectively. Type
float
is 32 bits wide and
type
double
is 64 bits wide.
Of the two,
double
is the most commonly used because all of the math functions in
Java's class library use
double
values. For example, the
sqrt( )
method (which is defined
by the standard
Math
class) returns a
double
value that is the square root of its
double
ar-
gument. Here,
sqrt( )
is used to compute the length of the hypotenuse, given the lengths of
the two opposing sides: