Data

Literal

Java

 

Literal Types

Java 8
boolean booleanVar = true;
int     integerVar = 12;
double  floatingPointVar = 1.618;
char    charVar = 'c';
String  stringVar = "Hello";
Object  nullVar = null;

Literals represent values, like: true, 12 or "Hello".

Literals in Java can be grouped into these categories:

  • Boolean
  • Integer
  • Floating-point
  • Character
  • String
  • Null
 

Boolean Literal

Java 8
boolean enable   = true;
boolean disable  = false;

There are 2 Boolean literals, true and false.

 

Integer Literal

Java 8
int ans1  = 42;        // Base10
int ans2  = 0b101010;  // Binary
int ans3  = 052;       // Octal
int ans4  = 0x2A;      // Hexadecimal
long ans5 = 42L;       // Long Base10

There are 5 Integer Literal representations:

  • Base10
  • Binary (base 2)
  • Octal (base 8)
  • Hexadecimal (base 16)
  • Long

L at the end of the ans5 value specifies that the value has long precision.

You can also use underscores (_) in your Integer literals for readability. So literals 42, 4_2 and 4__2 are equal.

All the variables defined here are equal to value 42.

 

Floating-Point Literal

Java 8
double pi1 = 3.14159;   // Normal
double pi2 = 314159E-5; // Scientific
double pi3 = 3.14159D;  // Double
float  pi4 = 3.14159F;  // Float

There are 4 Floating-point Literal representations:

  • Normal
  • Scientific
  • Literal Double
  • Literal Float

D and F at the end of the pi3 and pi4 values specify that these values have double and float precision.

If you don't specify D or F, the literal value is considered as double precision.

All the variables defined here are equal. (except pi4, because of different precision between floats and doubles)

 

Character Literal

Java 8
char FirstLetter = 'A';

A single letter can literally be specified using the character wrapped inside single quotes (').

 

String Literal

Java 8
String name = "Sam";

String is a sequence of characters.

A string can literally be specified using the sequence of characters wrapped inside double quotes (").

 

Null Literal

Java 8
Object nextElement = null;

null is used to represent the absence of a value.