Java Language Fundamentals (Part 4)

Data Types

All variables in the Java language must have a data type. A variable's data type determines the values that the variable can contain and the operations that can be performed on it. For example, the declaration

int value

declares that

value

is an integer (

int

).

There are two major categories of data types in the Java language: primitive and reference. The following table lists, by keyword, all of the primitive data types supported by Java:

Data Type	Description
Integral type
byte	Values from –128 to +127
short	Values from –32768 to +32767
int	Values from –21474883648 to +2147483647
long	Values from –9223372036854775808 to +9223372036854775807
Floating type
float	Values from –3.4E38 to +3.4E38
double	Values from –1.7E308 to +1.7E308
textual
char logical	Stores single character (16-bit Unicode character)
boolean	Can have one of two values (true or false)