Manipulating Data Using Methods - Java Programming: Comprehensive Concepts and Techniques - page 140

Table 3-2 Java Primitive Data Types

TYPE DESCRIPTION EXAMPLES

boolean stores data in only one of two states, as a true

logical value of true or false false

byte stores whole number values in 8-bit signed 75

locations from -128 to +127 -14

char stores any one of the 65,436 single 'a'

characters of the Unicode set, which 'M'

includes characters and symbols from
many languages

double stores numbers with up to 14 or 15 decimal 87.266975314

places as double-precision, floating-point 100D

values

float stores numbers with up to 6 or 7 decimals 349.135

as single-precision, floating-point values 954F

int stores whole number values in 32-bit signed 29387

locations from -2 31 to [phone]

long stores whole number values in 64-bit signed 13579286740

locations from approximately 7362L

-9 * 10 18 to +9 * 10 18 -1

short stores whole number values in 16-bit signed 619

-530

locations from -32,768 to +32,767

As you learned in Chapter 2, when an actual number or character displays as
data in code, it is called a literal. Generally speaking, a literal numeric value with
no decimal point is treated by the compiler as an int data type. Programmers can
specify that the data be treated as a long integer by putting an uppercase L or
lowercase l after the number, which overrides the default int storage. An upper-
case L is preferred, as it cannot be confused with the digit 1. In the same way, an
uppercase D or lowercase d after the literal forces that number to be considered a
double. The compiler considers a literal containing digits and a decimal point as
a double. Programmers may override that storage to specify a float by putting an
F or f after the number.
The two boolean literals are true and false. Programmers use the boolean
data type to store a comparative result or one that has only two states — such as
true or false, yes or no, 1 or 0 — as a logical value of true or false. A literal char
value is any single character between single quote marks.

Primitive Data Types Are Platform-Independent
In other programming languages, the format and size of primitive
data types may depend on the platform on which a program is
running. In contrast, the Java programming language specifies the
size and format of its primitive data types. Therefore, primitive
data types are platform-independent, which means programmers
do not have to worry about system dependencies.