Java Methods and Functions Explained in Depth with Examples

Java Methods and Functions Explained in Depth

Author: Gursehbaj Singh | Blog: DevMode

Methods in Java are blocks of code that perform a specific task. They help us write clean, reusable, and organized programs. In this guide, you will learn everything about Java methods in a simple and detailed way.

What is a Method in Java?

A method is a function that belongs to a class. It runs when it is called.

class Example {
    void showMessage() {
        System.out.println("Welcome to DevMode");
    }
}

Calling a Method

Example obj = new Example();
obj.showMessage();

Types of Methods in Java

1. Method Without Return Type

void greet() {
    System.out.println("Hello Java");
}

2. Method With Return Type

int add(int a, int b) {
    return a + b;
}

3. Static Method

static void display() {
    System.out.println("Static Method");
}

4. Method With Parameters

void printName(String name) {
    System.out.println(name);
}

Method Overloading

Same method name, different parameters.

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

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

Recursion in Java

A method calling itself.

int factorial(int n) {
    if(n == 1)
        return 1;
    else
        return n * factorial(n - 1);
}

Real Example: Calculator Using Methods

class Calculator {

    int add(int a, int b) {
        return a + b;
    }

    int subtract(int a, int b) {
        return a - b;
    }

    int multiply(int a, int b) {
        return a * b;
    }

    int divide(int a, int b) {
        return a / b;
    }
}

Why Methods Are Important?

• Code reuse
• Easy debugging
• Better readability
• Structured programming

Common Mistakes

• Forgetting return statement
• Wrong parameter types
• Calling non-static methods incorrectly

Conclusion

Methods are the backbone of Java programming. Once you master them, you can build large applications, create reusable logic, and write clean code easily.