The document discusses Java literals and variables. It defines character literals as representing Unicode characters using single quotes. String literals are defined as sequences of characters placed within double quotes. Null literals are defined as using the null keyword to assign null values to object references. Variables in Java must specify a data type and name, and can be initialized with a value. The data type can be either a primitive type or reference type.

1. ❏ JAVA CHARACTER LITERALS
❏ JAVA STRING LITERALS
LITERALS
AND
VARIABLES

2. ❏ JAVA CHARACTER LITERALS
❏ JAVA STRING LITERALS
LITERALS
AND
VARIABLES

3. Java Character Literals
● Character literals represents Unicode characters.
● Unicode provides a unique number for every
character:
○ No matter what the platform
○ No matter what the program
○ No matter what the language

4. ● To use a character literals, enclose the character in single quote
delimiter.
● Example:
○ The letter a is represented as ‘a’.
○ For special characters, a backslash (escape character) is used, followed by the
character code
■ ‘n’: new line or line feed (LF)
■ ‘t’; tab
■ ‘’: Backslash
■ ‘”: Single quotation mark
Java Character Literals

5. ● To use a character literals, enclose the character in single quote
delimiter.
● Example:
○ Characters from other languages or other symbols can be represented by Unicode
values
■ For Alphabet A, use ‘u0041’
■ For number 4 in devanagri script, use ‘u096A’
■ For hourglass symbol, use ‘u23f3’
Java Character Literals

6. ● Sequence of character is known as String
● String literal is values placed inside double quotation mark
● Example:
■ “”: Empty String
■ “ “; Single space
■ “A”: String containing single character A
■ “Java”: String for the text Java
■ “Hellon”: String containing Hello and newline or linefeed character (Note:
use of escape sequence)
■ “””: String containing double quote
Java String Literals

7. Java String Literals (example)
Example string literals program
Run Program (CTRL + F11)

8. Java null Literals
❏ Null literal is defined in Java source code file as null.
❏ Assign null literals to object reference variables
❏ Example
❏ String name = null;
❏ Object obj = null;
Note: String and Object are classes in Java

9. Variables in Java
● A variable has a:
■ Data type - indicates the type of value, variable can hold. Ex. Integer numbers, floating
point numbers, String and so on.
■ Name type - the variable name must follow rules for identifiers.
● Declare a variable as follows:
<data type> <name> [=initial value];
● The Java programming language is statically-typed, which means that the
<data type> must first be declared before variables can be used and it can’t
be changed later.

10. Variables in Java
● The <data type> can be either Primitive type or
Reference type
■ int x = 100; //Primitive type
■ Char var = ‘a’; //Primitive type
■ String name = “Trixie”; //Reference type
■ Car myCar; //Reference type

11. Variables in Java
Example string literals program
Run Program (CTRL + F11)