LEXICAL STRUCTURE

Boolean Literals

3.10.3

See

Float.MIN_VALUE

 ( 20.9.1) and

Float.MAX_VALUE

( 20.9.2); see also

Double.MIN_VALUE

 ( 20.10.1) and

Double.MAX_VALUE

( 20.10.2).

A compile time error occurs if a nonzero floating point literal is too large, so

that on rounded conversion to its internal representation it becomes an IEEE 754

infinity. A Java program can represent infinities without producing a compile time

error by using constant expressions such as

1f/0f

 or

 1d/0d

 or by using the pre 

defined constants

POSITIVE_INFINITY

 and

NEGATIVE_INFINITY

 of the classes

Float

 ( 20.9) and

Double

 ( 20.10).

A compile time error occurs if a nonzero floating point literal is too small, so

that, on rounded conversion to its internal representation, it becomes a zero. A

compile time error does not occur if a nonzero floating point literal has a small

value that, on rounded conversion to its internal representation, becomes a non 

zero denormalized number.

Predefined constants representing Not a Number values are defined in the

classes

Float

 and

Double

 as

Float.NaN

 ( 20.9.5) and

Double.NaN

 ( 20.10.5).

Examples of

float

 literals:

1e1f

2.f

.3f

0f

3.14f

6.022137e+23f

Examples of

double

 literals:

1e1

2.

.3

0.0

3.14

1e 9d

1e137

There is no provision for expressing floating point literals in other than deci 

mal radix. However, method

intBitsToFloat

 ( 20.9.23) of class

Float

 and

method

longBitsToDouble

 ( 20.10.22) of class

Double

 provide a way to

express floating point values in terms of hexadecimal or octal integer literals. For

example, the value of:

Double.longBitsToDouble(0x400921FB54442D18L)

is equal to the value of

Math.PI

 ( 20.11.2).

3.10.3   Boolean Literals

The

boolean

 type has two values, represented by the literals

true

 and

false

,

formed from ASCII letters.

A

boolean literal

 is always of type

boolean

.

BooleanLiteral: one of

true false

23