Java Assignment Operators

Introduction

Assignment operators in Java are used to assign values to variables. The most basic assignment operator is =, which assigns the value on the right-hand side to the variable on the left-hand side. Java also provides a range of compound assignment operators that combine arithmetic operations with assignment, making it easier to write concise and efficient code.

Key Points:

• Basic Assignment: The = operator assigns the right-hand value to the left-hand variable.
• Compound Assignment: Combines arithmetic operations with assignment for concise code.
• Multiple Uses: Commonly used for updating variables and performing arithmetic operations.

List of Assignment Operators

Java provides the following assignment operators:

Operator	Description	Example	Equivalent To
=	Simple assignment	a = b	a = b
+=	Addition assignment	a += b	a = a + b
-=	Subtraction assignment	a -= b	a = a - b
*=	Multiplication assignment	a *= b	a = a * b
/=	Division assignment	a /= b	a = a / b
%=	Modulus assignment	a %= b	a = a % b
&=	Bitwise AND assignment	a &= b	a = a & b
|=	Bitwise OR assignment	a |= b	a = a | b
^=	Bitwise XOR assignment	a ^= b	a = a ^ b
<<=	Left shift assignment	a <<= b	a = a << b
>>=	Right shift assignment	a >>= b	a = a >> b
>>>=	Unsigned right shift assignment	a >>>= b	a = a >>> b

Detailed Examples of Assignment Operators

Let’s explore each assignment operator with examples.

1. Simple Assignment (=)

The = operator assigns the value on the right-hand side to the variable on the left-hand side.

public class SimpleAssignmentExample { public static void main(String[] args) { int a = 5; int b = 10; a = b; // Assign the value of b to a System.out.println("a: " + a); // Output: a: 10 } } 

Explanation:

• Assignment: The value of b (which is 10) is assigned to a.

Output:

a: 10 

2. Addition Assignment (+=)

The += operator adds the right-hand operand to the left-hand operand and assigns the result to the left-hand operand.

public class AdditionAssignmentExample { public static void main(String[] args) { int a = 5; a += 3; // Equivalent to a = a + 3 System.out.println("a: " + a); // Output: a: 8 } } 

Explanation:

• Addition Assignment: The value 3 is added to a, and the result is stored back in a.

Output:

a: 8 

3. Subtraction Assignment (-=)

The -= operator subtracts the right-hand operand from the left-hand operand and assigns the result to the left-hand operand.

public class SubtractionAssignmentExample { public static void main(String[] args) { int a = 5; a -= 2; // Equivalent to a = a - 2 System.out.println("a: " + a); // Output: a: 3 } } 

Explanation:

• Subtraction Assignment: The value 2 is subtracted from a, and the result is stored back in a.

Output:

a: 3 

4. Multiplication Assignment (*=)

The *= operator multiplies the left-hand operand by the right-hand operand and assigns the result to the left-hand operand.

public class MultiplicationAssignmentExample { public static void main(String[] args) { int a = 5; a *= 4; // Equivalent to a = a * 4 System.out.println("a: " + a); // Output: a: 20 } } 

Explanation:

• Multiplication Assignment: The value 4 is multiplied by a, and the result is stored back in a.

Output:

a: 20 

5. Division Assignment (/=)

The /= operator divides the left-hand operand by the right-hand operand and assigns the result to the left-hand operand.

public class DivisionAssignmentExample { public static void main(String[] args) { int a = 20; a /= 4; // Equivalent to a = a / 4 System.out.println("a: " + a); // Output: a: 5 } } 

Explanation:

• Division Assignment: The value of a is divided by 4, and the result is stored back in a.

Output:

a: 5 

6. Modulus Assignment (%=)

The %= operator calculates the modulus of the left-hand operand with the right-hand operand and assigns the result to the left-hand operand.

public class ModulusAssignmentExample { public static void main(String[] args) { int a = 10; a %= 3; // Equivalent to a = a % 3 System.out.println("a: " + a); // Output: a: 1 } } 

Explanation:

• Modulus Assignment: The remainder of a divided by 3 is stored back in a.

Output:

a: 1 

Conclusion

Java’s assignment operators are crucial for manipulating variables and performing arithmetic operations in a concise and efficient manner. By using compound assignment operators, developers can write cleaner and more maintainable code.

Summary:

• Simple Assignment (=): Assigns the right-hand value to the left-hand variable.
• Addition Assignment (+=): Adds the right-hand value to the left-hand variable.
• Subtraction Assignment (-=): Subtracts the right-hand value from the left-hand variable.
• Multiplication Assignment (*=): Multiplies the left-hand variable by the right-hand value.
• Division Assignment (/=): Divides the left-hand variable by the right-hand value.
• Modulus Assignment (%=): Computes the remainder of dividing the left-hand variable by the right-hand value.