Java Tutorial - Java Data Type

Java defines eight primitive types of data: byte, short, int, long, char, float, double, and boolean.

Primitive TypeReserved WordSizeMin ValueMax Value
Characterchar16-bitUnicode 0Unicode 216 - 1
Byte integerbyte8-bit-128+127
Short integershort16-bit-215+215 - 1
Integerint32-bit-231+231 - 1
Long integerlong64-bit-263+263 - 1
Double precision floating-pointdouble64-bit4.9e-3241.8e+308

byte, short, int, and long are for whole-valued signed numbers. float and double are fractional precision numbers.

char represents symbols in a character set, like letters and numbers. boolean represents true/false values.

Java Integers

Java defines four integer types: byte, short, int, and long.

Integer types are signed and can have positive and negative values.

The width and ranges of these integer types vary widely:

long64-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
int32-2,147,483,648 to 2,147,483,647
short16-32,768 to 32,767
byte8-128 to 127

Floating Point Types

There are two kinds of floating-point types: float and double. float type represents single-precision numbers. double type stores double-precision numbers.

Floating-Point Types width and ranges are shown here:

NameWidth in BitsApproximate Range
double644.9e-324 to 1.8e+308
float321.4e-045 to 3.4e+038