What is a Method in Java?

A method in Java is a block of code that performs a specific task. Methods help to reuse code — you write it once and call it whenever needed.

Syntax of a Method:

returnType methodName(parameter1, parameter2, ...) {
    // code to be executed
    return value;
}

Types of Methods:

1. Predefined Methods – Already available in Java (like System.out.println()).
2. User-defined Methods – Created by the programmer to perform specific tasks.

Example 1: A Simple Method (No Parameters, No Return)

public class HelloWorld {

    // method definition
    public static void greet() {
        System.out.println("Hello, welcome to Java!");
    }

    public static void main(String[] args) {
        greet(); // method call
    }
}

Output:

Hello, welcome to Java!

Example 2: Method with Parameters

public class Calculator {

    // method with parameters
    public static void add(int a, int b) {
        int sum = a + b;
        System.out.println("Sum: " + sum);
    }

    public static void main(String[] args) {
        add(5, 10); // method call with arguments
    }
}

Output:

Sum: 15

Example 3: Method with Return Value

public class Multiply {

    // method returns an int
    public static int multiply(int x, int y) {
        return x * y;
    }

    public static void main(String[] args) {
        int result = multiply(4, 5);
        System.out.println("Result: " + result);
    }
}

Output:

Result: 20

Example 4: Method Overloading (Same name, different parameters)

public class OverloadExample {

    public static int square(int x) {
        return x * x;
    }

    public static double square(double x) {
        return x * x;
    }

    public static void main(String[] args) {
        System.out.println("Square of 5: " + square(5));
        System.out.println("Square of 2.5: " + square(2.5));
    }
}

Output:

Square of 5: 25
Square of 2.5: 6.25

Why Use Methods?

• Reusability – Avoid repeating code
• Modularity – Break big problems into smaller parts
• Maintainability – Easy to update or debug
• Readability – Improves structure and clarity