Operators in Java

In this tutorial, you will travel through various operators used in Java to handle logical, arithmetical, and so and so calculations with the aid of simple and easy examples. 

What are operators?

Operators are unique symbols that perform some kind of computation. The objects or values on which operators act are known as operands and the combination of operators and operands are termed as expressions. For instance,  3+6=9 is an expression with 3, 6, and 9 as the operands, and  + and = are operators. 

Classification of Operators

Based on the type of operations, java operators are classified into 6 main categories

Java Arithmetic operators

Arithmetic operators in java are used to perform calculations like addition, subtraction, multiplication, etc on variables and data. The popular operators associated with arithmetic calculations are tabulated below for easy reference.

public class OpEx {

 public static void main(String[] args) {
  
  //declaring integer variables
  int a =10, b= 2;
  
  // + operator for addition
   System.out.println("a + b = " + (a + b));
  
  //  - operator for subtraction
   System.out.println("a - b = " + (a - b));
   
  // * operator for multiplication
   System.out.println("a * b = " + (a * b));
  
  // / operator for division
   System.out.println("a / b = " + (a / b));
   
  // % operator for division to obtain remainder
  System.out.println("a % b = " + (a % b));
 }

}

 

Output:

a + b = 12
a - b = 8
a * b = 20
a / b = 5
a % b = 0

Java relational operators

Relational operators do compare the data provided on the LHS and RHS to give binary outputs i.e. True or False. Here are the six operators demonstrated using the two operands 6 and 9.

public class OpEx {

    public static void main(String[] args) {

        // declaring variables
        int a = 6, b = 9;

        // value of a and b
        System.out.println("a = " + a + " and b = " + b);

        // == operator
        System.out.println(a == b); // 6 == 9 returns false

        // != operator
        System.out.println(a != b); // 6 != 9 returns true

        // > operator
        System.out.println(a > b); // 6 > 9 returns false

        // < operator
        System.out.println(a < b); // 6 < 9 returns true

        // >= operator
        System.out.println(a >= b); // 6 >= 9 returns false

        // <= operator
        System.out.println(a <= b); // 6 <= 9 returns true
    }
}
 

Java logical operators

Logical operators perform binary operations to process data at the machine level ( logic gates like AND,  OR,  NOR, NAND, etc.). Here is the description of three basic logical operators in java that is extensively used in decision making.

Truth table of Logical Operators are given below :

Examine the below example to understand the principle of logical operator.

public class OpEx {

    public static void main(String[] args) {

        // && operator
        System.out.println((2 > 3) && (3 == 3)); // false


        // || operator
        System.out.println((2 > 3) || (3 == 3)); // true


        // ! operator
        System.out.println(!(3 == 3)); // false

    }
}
 

Java unary operators

Unary operators are those operators that work with only one operand. In the previous section , you have seen the operator for negation(!) which acts only on one operand. Similarly following are the different types of unary operators used in java.

Example: Unary Operator

public class OpEx {

 public static void main(String[] args) {
  
  int status = +1;
        System.out.println(status); // status is now 1

        status--;
        System.out.println(status); // After decrement status is now 0

        status++;
        System.out.println(status);  // after increment status is now 1

        status = -status;
        System.out.println(status);  // result is now -1

        boolean flag = false;
        System.out.println(flag);   // false 
        System.out.println(!flag); // true
  
  }
 }

 

Java bitwise shift operators

These are the most basic and elementary types of operators. The bitwise operator, as its name suggests, manipulates bit-level data. Specifically, the bitwise operators perform operations on integer data at their bit levels.

The bitwise operators are of 7 types:-

BITWISE AND OPERATOR

The first operator '&'(bitwise AND) is of AND type which copies any bit to the result if the bit exists in both operands. More specifically the existence of a bit is represented with binary 1 and the counterpart with binary 0. Here is a truth table showing the use of the Bitwise AND operator which is much similar to the logical operators.

For example, the Binary representation of 3 is 0000 0011 and that of 7 is 0000 0111. Let’s see what will be the result of 3 & 7:

Now let’s have a look how to use Bitwise AND operator in java:

public class BAndEx {
    public static void main(String[] args) {
        int x = 3, y = 7;
        System.out.println("x & y = " + (x & y)); // prints 3
    }
}
 

BITWISE OR OPERATOR

Bitwise OR symbolised as ‘I’ functions as a logical OR operator. It replicates a bit(1), if it exists in either or both of the operands.The truth table has demonstrated the working of Bitwise OR operator.

Let’s try to understand how the bitwise OR operator works on two binary numbers 3 and 7.

Below java program shows the operation of Bitwise OR operator.

public class BOREx {
    public static void main(String[] args) {
        int x = 3, y = 7;
        System.out.println("x | y = " + (x | y)); // prints 7 
    }
}