Java Operators

Operators are symbols that perform operations on variables and values. For example,+ is an operator used for addition, while * is also an operator used for multiplication.

Operators in Java can be classified into 5 types:

1. Arithmetic Operators
2. Assignment Operators
3. Relational Operators
4. Logical Operators
5. Unary Operators
6. Bitwise Operators

1. Java Arithmetic Operators

Arithmetic operators are used to perform arithmetic operations on variables and data. For example,

a + b;

Here, the + operator is used to add two variables a and b. Similarly, there are various other arithmetic operators in Java.

Example 1: Arithmetic Operators

class Main {
  public static void main(String[] args) {

    // declare variables
    int a = 12, b = 5;

    // addition operator
    System.out.println("a + b = " + (a + b));

    // subtraction operator
    System.out.println("a - b = " + (a - b));

    // multiplication operator
    System.out.println("a * b = " + (a * b));

    // division operator
    System.out.println("a / b = " + (a / b));

    // modulo operator
    System.out.println("a % b = " + (a % b));
  }
}

Output

a + b = 17
a - b = 7
a * b = 60
a / b = 2
a % b = 2

In the above example, we have used +, -, and * operators to compute addition, subtraction, and multiplication operations.

/ Division Operator

Note the operation, a / b in our program. The / operator is the division operator.

If we use the division operator with two integers, then the resulting quotient will also be an integer. And, if one of the operands is a floating-point number, we will get the result will also be in floating-point.

In Java,

(9 / 2) is 4
(9.0 / 2) is 4.5
(9 / 2.0) is 4.5
(9.0 / 2.0) is 4.5

% Modulo Operator

The modulo operator % computes the remainder. When a = 7 is divided by b = 4, the remainder is 3.

2. Java Assignment Operators

Assignment operators are used in Java to assign values to variables. For example,

int age;
age = 5;

Here, = is the assignment operator. It assigns the value on its right to the variable on its left. That is, 5 is assigned to the variable age.

Let’s see some more assignment operators available in Java.

Example 2: Assignment Operators

class Main {
  public static void main(String[] args) {

    // create variables
    int a = 4;
    int var;

    // assign value using =
    var = a;
    System.out.println("var using =: " + var);

    // assign value using =+
    var += a;
    System.out.println("var using +=: " + var);

    // assign value using =*
    var *= a;
    System.out.println("var using *=: " + var);
  }
}

Output

var using =: 4
var using +=: 8
var using *=: 32

3. Java Relational Operators

Relational operators are used to check the relationship between two operands. For example,

// check is a is less than b
a < b;

Here, > operator is the relational operator. It checks if a is less than b or not.

It returns either true or false.

Example 3: Relational Operators

class Main {
  public static void main(String[] args) {

    // create variables
    int a = 7, b = 11;

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

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

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

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

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

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

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

4. Java Logical Operators

Logical operators are used to check whether an expression is true or false. They are used in decision making.

Example 4: Logical Operators

class Main {
  public static void main(String[] args) {

    // && operator
    System.out.println((5 > 3) && (8 > 5));  // true
    System.out.println((5 > 3) && (8 < 5));  // false

    // || operator
    System.out.println((5 < 3) || (8 > 5));  // true
    System.out.println((5 > 3) || (8 < 5));  // true
    System.out.println((5 < 3) || (8 < 5));  // false

    // ! operator
    System.out.println(!(5 == 3));  // true
    System.out.println(!(5 > 3));  // false
  }
}

Working of Program

• (5 > 3) && (8 > 5) returns true because both (5 > 3) and (8 > 5) are true.
• (5 > 3) && (8 < 5) returns false because the expression (8 < 5) is false.
• (5 < 3) || (8 > 5) returns true because the expression (8 > 5) is true.
• (5 > 3) && (8 > 5) returns true because the expression (5 > 3) is true.
• (5 > 3) && (8 > 5) returns false because both (5 < 3) and (8 < 5) are false.
• !(5 == 3) returns true because 5 == 3 is false.
• !(5 > 3) returns false because 5 > 3 is true.

5. Java Unary Operators

Unary operators are used with only one operand. For example, ++ is a unary operator that increases the value of a variable by 1. That is, ++5 will return 6.

Different types of unary operators are:

Increment and Decrement Operators

Java also provides increment and decrement operators: ++ and - - respectively. ++ increases the value of the operand by 1, while - - decrease it by 1. For example,

int num = 5;

// increase num by 1
++num;

Here, the value of num gets increased to 6 from its initial value of 5.

Example 5: Increment and Decrement Operators

class Main {
  public static void main(String[] args) {

    // declare variables
    int a = 12, b = 12;
    int result1, result2;

    // original value
    System.out.println("Value of a: " + a);

    // increment operator
    result1 = ++a;
    System.out.println("After increment: " + result1);

    System.out.println("Value of b: " + b);

    // decrement operator
    result2 = --b;
    System.out.println("After decrement: " + result2);
  }
}

Output

Value of a: 12
After increment: 13
Value of b: 12
After decrement: 11

In the above program, we have used the ++ and - - operator as prefixes (++a, - -b). We can also use these operators as postfix (a++, b++).

There is a slight difference when these operators are used as prefix versus when they are used as a postfix.

6. Java Bitwise Operators

Bitwise operators in Java are used to perform operations on individual bits. For example,

Bitwise complement Operation of 35

35 = 00100011 (In Binary)

~ 00100011
  ________
   11011100  = 220 (In decimal)

Here, ~ is a bitwise operator. It inverts the value of each bit (0 to 1 and 1 to 0).

The various bitwise operators present in Java are:

These operators are not generally used in Java. To learn more, visit Java Bitwise and Bit Shift Operators.

7. Other operators

Besides these operators, there are other additional operators in Java.

Java instanceof Operator

The instanceof operator checks whether an object is an instanceof a particular class. For example,

class Main {
  public static void main(String[] args) {

    String str = "";
    boolean result;

    // checks if str is an instance of
    // the String class
    result = str instanceof String;
    System.out.println("Is str an object of String? " + result);
  }
}

Output

Is str an object of String? true

Here, str is an instance of the String class. Hence, the instanceof operator returns true. To learn more, visit Java instanceof.

Java Ternary Operator

The ternary operator (conditional operator) is shorthand for the if-then-else statement. For example,

variable = Expression ? expression1 : expression2

Here’s how it works.

• If the Expression is true, expression1 is assigned to the variable.
• If the Expression is false, expression2 is assigned to the variable. Let’s see an example of a ternary operator.

class Java {
  public static void main(String[] args) {

    int februaryDays = 29;
    String result;

    // ternary operator
    result = (februaryDays == 28) ? "Not a leap year" : "Leap year";
    System.out.println(result);
  }
}

Output

Leap year

In the above example, we have used the ternary operator to check if the year is a leap year or not. To learn more, visit the Java ternary operator.

Now that you know about Java operators, it’s time to know about the order in which operators are evaluated. To learn more, visit Java Operator Precedence.