2. Operators in Java

Operators in Java

Operators in Java are symbols that perform operations on variables and values. Java supports various types of operators, such as arithmetic, assignment, comparison, and logical operators. Understanding these operators is essential for writing efficient and error-free code.

a. Arithmetic Operations

This method performs basic arithmetic and demonstrates increment/decrement operators.

• Parameters: Two integers (a and b).
• Operations:
  • Addition (a + b)
  • Subtraction (a - b)
  • Multiplication (a * b)
  • Division (a / b)
  • Modulus (a % b)
  • Post-increment (a++): Value is used before incrementing.
  • Pre-increment (++a): Value is incremented before use.
  • Post-decrement (b--): Value is used before decrementing.
  • Pre-decrement (--b): Value is decremented before use.
• Output: Prints the result of each operation.

b. Assignment Operations

This method demonstrates compound assignment operators.

• Parameters: Two integers (a and b).
• Operations:
  • a += b (Addition assignment)
  • a -= b (Subtraction assignment)
  • a *= b (Multiplication assignment)
  • a /= b (Division assignment)
  • a %= b (Modulus assignment)
• Output: Prints the result of each assignment.

c. Comparison Operations

This method demonstrates relational operators.

• Parameters: Two integers (a and b).
• Operations:
  • Equality (a == b)
  • Inequality (a != b)
  • Greater than (a > b)
  • Less than (a < b)
  • Greater than or equal to (a >= b)
  • Less than or equal to (a <= b)
• Output: Prints the result of each comparison.

d. Logical Operations

This method demonstrates logical operators.

• Parameters: Two integers (a and b).
• Operations:
  • Logical AND (&&): True if both conditions are true.
  • Logical OR (||): True if at least one condition is true.
  • Logical NOT (!): Negates the condition.
• Output: Prints the result of each logical operation.

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Key Points to Remember

1. Arithmetic Operators:

   • Postfix (a++, b--) vs. Prefix (++a, --b) behavior.
   • Integer division truncates the result (e.g., 5 / 2 results in 2).

2. Assignment Operators:

   • Compact syntax for updating variables (e.g., a += b instead of a = a + b).

3. Comparison Operators:

   • Used to compare two values, returning a boolean result.

4. Logical Operators:

   • Combine multiple conditions and return a boolean result.

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Example Code

import java.util.Scanner;
 
public class Operators {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
 
        System.out.print("Enter the first number: ");
        int a = input.nextInt();
        System.out.print("Enter the second number: ");
        int b = input.nextInt();
 
        // Arithmetic Operations
        System.out.println("Sum: " + (a + b));
        System.out.println("Subtract: " + (a - b));
        System.out.println("Multiply: " + (a * b));
        System.out.println("Divide: " + (a / b));
        System.out.println("Mod: " + (a % b));
        System.out.println("Increment: " + a++);
        System.out.println("Increment2: " + ++a);
        System.out.println("Decrement: " + b--);
        System.out.println("Decrement2: " + --b);
 
        // Assignment Operations
        a = 5;
        b = 3;
        a += b;
        System.out.println("a += b: " + a);
        a = 5;
        b = 3;
        a -= b;
        System.out.println("a -= b: " + a);
        a = 5;
        b = 3;
        a *= b;
        System.out.println("a *= b: " + a);
        a = 5;
        b = 3;
        a /= b;
        System.out.println("a /= b: " + a);
        a = 5;
        b = 3;
        a %= b;
        System.out.println("a %= b: " + a);
 
        // Comparison Operations
        a = 5;
        b = 3;
        System.out.println("a == b: " + (a == b));
        System.out.println("a != b: " + (a != b));
        System.out.println("a > b: " + (a > b));
        System.out.println("a < b: " + (a < b));
        System.out.println("a >= b: " + (a >= b));
        System.out.println("a <= b: " + (a <= b));
 
        // Logical Operations
        a = 5;
        b = 3;
        System.out.println("a == b && a > b: " + (a == b && a > b));
        System.out.println("a == b || a > b: " + (a == b || a > b));
        System.out.println("!(a == b): " + !(a == b));
    }
}

Example Run

Input:

Enter the first number: 5
Enter the second number: 3

Output:

Sum: 8
Subtract: 2
Multiply: 15
Divide: 1
Mod: 2
Increment: 5
Increment2: 7
Decrement: 3
Decrement2: 1
a += b: 8
a -= b: 5
a *= b: 15
a /= b: 5
a %= b: 2
a == b: false
a != b: true
a > b: true
a < b: false
a >= b: true
a <= b: false
a == b && a > b: false
a == b || a > b: true
!(a == b): true