JAVA Operators

Operators: Operators are special symbol that perform specific operation on one, two or three operands and then return a result.

Operand: Operand is a term used to describe any object that is manipulated by an operator.

Example:

int value = 15+12;

Here ‘+’ is the operator and 15 & 12 are operand.

There are many operators in Java, classified according to there features:

• Arithmetic Operator
• Unary Operator
• Binary Operator
• Shift Operator
• Relational Operator
• Bitwise Operator
• Logical Operator
• Ternary Operator
• Assignment Operator

1. Arithmetic Operator: They are used to perform five basic arithmetic operations:

• + : Addition
• – : Subtraction
• * : Multiplication
• / : Division
• % : Modulus

Arithmetic operators are further divided into two types:

• Unary Operators
• Binary Operators

2. Unary Operator: They performs operations on single operand.

• Unary minus(-): It is  used for reversing the sign of the operand’s value.
• Unary plus(+): It  indicates that the value is positive (however numbers are considered positive without this operator).
• Increment operator(++):  This operator adds 1 to its operand. This operator is in two variant:

• • Post-Increment: In this the value is first used for computing the result and then the value is incremented by 1.
  • Pre-Increment: In this the value is incremented first by 1, and then the result is computed.
• Decrement operator(–):This operator substracts 1 from its operand. This operator is in two variant:
  • Post-Decrement: In this the value is first used for computing the result and then the value is decremented by 1.
  • Pre-Decrement: In this the value is decremented first by 1, and then the result is computed.
• Logical not operator(!): It is used for inverting a Boolean value.

3. Binary Operator: They performs operations on two operands.

• Addition Operator(+)
• Subtraction Operator(-)
• Multiplication Operator(*)
• Division Operator(/)
• Modulus Operator(%)

4. Relational Operator: The relational operator determines the relationship among two operands.

The output results in Boolean value.

 

Operator	Meaning of Operator	Example
>	Greater than	(2>1) returns True
<	Less than	(2<1) returns False
>=	Greater than equal to	(2>=1) returns True
<=	Less than equal to	(2<=1) returns False
==	Equal to	(2==1) returns False
!=	Not equal to	(2!=1) returns True

5. Logical Operator: Logical operators are used to determine the logic between variables or value.

Operator	Meaning	Example
&&	Logical AND (Returns True if both statements are true)	If a = 2 and b = 3 then, expression ((a==2) && (b==2)), returns False.
||	Logical OR (Returns True if one of the statement is true)	If a = 2 and b = 3 then, expression ((a==2) || (b==2)), returns True.
!	Logical NOT (Reverse the result, returns false if the result is true)	If a = 5 then, expression !(a==5) returns False.

6. Bitwise Operator: Bitwise operator works on bit and performs bit-by-bit operations.

Operator	Description
&	Bitwise AND Copies a bit to the result if it exists in both operands.
|	Bitwise OR Copies a bit to the result if it exists in either operands.
^	Bitwise XOR Copies a bit if it is set in one operand but not both.

7. Shift Operator: A shift operator performs bit manipulation on data by shifting the bits of its first operand right or left.

Operator	Description
<<	Left Shift (A<<B) The left operand value is moved left by the number of bits specified by the right operand.
>>	Right Shift (A>>B) The left operand value is moved right by the number of bits specified by the right operand.
>>>	Zero fill Right Shift (A>>>B) The left operand value is moved right by the number of bits specified by the right operand and shifted values are filled up with zero.

8. Assignment Operator: Assignment operators are used to assign values to the operators.

Operator	Meaning of Operator	Example
=	Simple Assignment Assigns values from right side operands to left side operand	C = A+B will assign value of A+B to C
+=	Add AND Assignment It adds right operand to left operand and assigns the result to left side operand	C+=A  =>  C = C+A
-=	Substract AND Assignment It substract right operand from the left operand and assigns the result to left side operand	C-=A  =>  C = C-A
*=	Multiply AND Assignment It multiplies right operand with the left operand and assigns the result to left side operand	C*=A  =>  C = C*A
/=	Divide AND Assignment It divides left operand with the right operand and assigns the result to left side operand	C/=A  =>  C = C/A
%=	Modulus AND Assignment It modulus two operands and assigns the result to left side operand	C%=A  =>  C = C%A

5. Logical Operator: Logical operators are used to determine the logic between variables or value.

Operator	Meaning	Example
&&	Logical AND (Returns True if both statements are true)	If a = 2 and b = 3 then, expression ((a==2) && (b==2)), returns False.
||	Logical OR (Returns True if one of the statement is true)	If a = 2 and b = 3 then, expression ((a==2) || (b==2)), returns True.
!	Logical NOT (Reverse the result, returns false if the result is true)	If a = 5 then, expression !(a==5) returns False.

9. Conditional Operator: Conditional operator is also known as ternary operator.

This operator requires 3 operands.

Syntax:

result = expresion1? expresion2:expresion3;

Example:

result = (marks >= 50)? "True":"False";

Precedence and Associativity of operators.

Precedence: Precedence defines the order in which given mathematical expression is evaluated.

Operators with higher precedence is evaluated first and operators with lower precedence is evaluated at last.

Example:

(+,-) has less precedence compared to (*,/), so (*,/) are evaluated first.

Associativity: Operators with same precedence follow operator associativity.

Associativity is the direction of execution of operator.  It can either be left to right or right to left.

Example:

*  /        =>    L to R

+  –       =>    L to R

++  =    =>   R to L

 

Operator Precedence and Associativity

Operators	Precedence	Associativity
postfix increment and decrement	++ —	left to right
prefix increment and decrement, and unary	++ — + – ~ !	right to left
multiplicative	* / %	left to right
additive	+ –	left to right
shift	<< >> >>>	left to right
relational	< > <= >= instanceof	left to right
equality	== !=	left to right
bitwise AND	&	left to right
bitwise exclusive OR	^	left to right
bitwise inclusive OR	|	left to right
logical AND	&&	left to right
logical OR	||	left to right
ternary	? :	right to left
assignment	= += -= *= /= %= &= ^= |= <<= >>= >>>=	right to left

Resulting data type after arithmetic:

byte + short = int

short + int = int

long + float = float

char + int = int 

char + short = int 

long + double = double

float + double = double