Java Operators

Operators are used to performing operations on variables and values.

In the example below, the numbers 120 and 80 are operands and the + sign is an operator:

int x = 120 + 80;

Although the + operator is often used to add together two values, like in the example above, it can also be used to add together a variable and a value, or a variable and a variable:

int sum1 = 100 + 50;        // 150 (100 + 50)
int sum2 = sum1 + 250;      // 400 (150 + 250)
int sum3 = sum2 + sum2;     // 800 (400 + 400)

In Java operators divided into the following groups:

Arithmetic Operators

Arithmetic operators are used to performing common mathematical operations.

Operator Name Description Example
+ Addition Adds together two values x + y
- Subtraction Subtracts one value from another x - y
* Multiplication Multiplies two values x * y
/ Division Divides one value from another x / y
% Modulus Returns the division remainder x % y
++ Increment Increases the value of a variable by 1 ++x
-- Decrement Decreases the value of a variable by 1 --x

 

Assignment Operators

Assignment operators are used to assign values to variables.

In the example below, we use the assignment operator (=) to assign the value 10 to a variable called x:

= Simple assignment operator. Assigns values from right side operands to left side operand. C = A + B will assign value of A + B into C
+= Add AND assignment operator. It adds right operand to the left operand and assigns the result to the left operand. C += A is equivalent to C = C + A
-= Subtract AND assignment operator. It subtracts right operand from the left operand and assigns the result to the left operand. C -= A is equivalent to C = C – A
*= Multiply AND assignment operator. It multiplies right operand with the left operand and assigns the result to the left operand. C *= A is equivalent to C = C * A
/= Divide AND assignment operator. It divides left operand with the right operand and assigns the result to the left operand. C /= A is equivalent to C = C / A
%= Modulus AND assignment operator. It takes modulus using two operands and assigns the result to the left operand. C %= A is equivalent to C = C % A
<<= Left shift AND assignment operator. C <<= 2 is same as C = C << 2
>>= Right shift AND assignment operator. C >>= 2 is same as C = C >> 2
&= Bitwise AND assignment operator. C &= 2 is same as C = C & 2
^= bitwise exclusive OR and assignment operator. C ^= 2 is same as C = C ^ 2
|= bitwise inclusive OR and assignment operator. C |= 2 is same as C = C | 2

 

Comparison Operators

Comparison operators are used to comparing two values:

Operator Name Example
== Equal to x == y
!= Not equal x != y
> Greater than x > y
< Less than x < y
>= Greater than or equal to x >= y
<= Less than or equal to x <= y

 

Logical Operators

Logical operators are used to determining the logic between variables or values:

Operator Name Description Example
&&  Logical and Returns true if both statements are true x < 5 &&  x < 10
||  Logical or Returns true if one of the statements is true x < 5 || x < 4
! Logical not Reverse the result, returns false if the result is true !(x < 5 && x < 10)

 

Bitwise Operators

Java defines several bitwise operators, which can be applied to the integer types, long, int, short, char, and byte.

Operator Description Example
& (bitwise and) Binary AND Operator copies a bit to the result if it exists in both operands. (A & B) will give 12 which is 0000 1100
| (bitwise or) Binary OR Operator copies a bit if it exists in either operand. (A | B) will give 61 which is 0011 1101
^ (bitwise XOR) Binary XOR Operator copies the bit if it is set in one operand but not both. (A ^ B) will give 49 which is 0011 0001
~ (bitwise compliment) Binary One's Complement Operator is unary and has the effect of 'flipping' bits. (~A ) will give -61 which is 1100 0011 in 2's complement form due to a signed binary number.
<< (left shift) Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand. A << 2 will give 240 which is 1111 0000
>> (right shift) Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand. A >> 2 will give 15 which is 1111
>>> (zero fill right shift) Shift right, zero fill operator. The left operands value is moved right by the number of bits specified by the right operand and shifted values are filled up with zeros. A >>>2 will give 15 which is 0000 1111