Constants in java

Constants in java refers to fixed value in java that do not change during the execution of a program.

Integer Constants:

An interger constant refers to a sequence of digits. There are three types of integers, Decimal integers, Octal integer and Hexadecimal integer.

Decimal integer constant is a set of digits, o through 0, preceded by an optional min sign, Examples are:

123 -321 0 654321

Octal integer constant consists of any combination of digits from the set 0 through 7, with a leading 0. Examples are:

037 0 0453 05512

A sequence of digits preceded by 0x or 0X is considered as hexadecimal integers, they may also includes alphabets A through F or a through f. Examples are:

0x2 0x9F 0x4f

Octal and hexadecimal numbers are rarely use in programming.

Real Constants:

Interegr numbers are inadequate to represent the quantity that vary continuously, such as distance, tempratures, prices etc. These quantities represents by numbers, such numbers are called as real constants. Examples are:

0.083 -0.75 45.3

Character Constants:

Character constant contains a single character enclose within a pair of single quote mark. Examples are:

'5' 'x' ';' ' '

String Constants:

A String constants is a sequence of characters enclosed between double quotes. The characters may be alphabets, digits, special charactors and blank spaces. Examples are:

"Hellow Java" "1997" "?...!" "5+6"

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