Java Methods

1. Declaring and Calling Methods

A method is defined once and can be called multiple times. A basic method includes:

• Return type (or void if nothing is returned)
• Method name
• Optional parameters
• Method body

Try example: Online Java Compiler

public class MethodDemo {

    static void greet() {
        System.out.println("Welcome to VINAR TECH Tutorials");
    }

    public static void main(String[] args) {
        greet();  // Calling the method
        greet();  // You can call it multiple times
    }
}

2. Parameters and Return Types

You can pass values to a method (known as parameters). Methods may also return a value.

Try example: Online Java Compiler

public class ParameterDemo {

    static int add(int a, int b) {
        return a + b;  // Method returns an integer value
    }

    public static void main(String[] args) {

        int result = add(10, 20);
        System.out.println("Sum = " + result);
    }
}

Types of Methods

• Void methods: Perform an action but return nothing.
• Non-void methods: Return a computed value.
• Static methods: Called without creating an object.
• Instance methods: Require an object of the class.

3. Method Overloading

Method overloading means defining multiple methods with the same name but different parameter lists.

Try example: Online Java Compiler

public class OverloadDemo {

    static int sum(int a, int b) {
        return a + b;
    }

    static double sum(double a, double b) {
        return a + b;
    }

    public static void main(String[] args) {

        System.out.println(sum(5, 10));       // int version
        System.out.println(sum(5.5, 2.7));    // double version
    }
}

4. Returning Objects from Methods

Methods can return not only primitive values but also objects.

Try example: Online Java Compiler

class User {
    String name;

    User(String name) {
        this.name = name;
    }
}

public class ObjectReturnDemo {

    static User createUser(String name) {
        return new User(name);
    }

    public static void main(String[] args) {
        User u = createUser("VINAR TECH");
        System.out.println("Created User: " + u.name);
    }
}

5. Recursion

Recursion occurs when a method calls itself. Every recursive method must have:

• A base condition (stopping point)
• A recursive step (calls itself with new input)

Try example: Online Java Compiler

public class RecursionDemo {

    static int factorial(int n) {

        if (n == 0) {
            return 1;       // Base case
        }

        return n * factorial(n - 1);  // Recursive call
    }

    public static void main(String[] args) {

        System.out.println("Factorial of 5 = " + factorial(5));
    }
}

6. Best Practices for Methods

• Use meaningful method names (e.g., calculateTotal())
• Keep methods short and focused on a single task
• Organize related methods inside proper classes
• Use method overloading to avoid confusing method names
• Use recursion only when it simplifies logic