My Third Step in Java: Methods, Main Method, Objects, and a Mini Calculator

I recently started learning Java, and in my first few sessions we covered some of the most important basics. In this post, I want to walk through what I learned: methods, the main method, objects, how to call methods, and even building a small calculator program.

Methods in Java

Methods are blocks of code that perform a specific task. They make code reusable, organized, and easier to read.

We looked at four different types of methods:

1.With return type, without arguments

2.With return type, with arguments

3.Without return type, with arguments

4.Without return type, without arguments

Example

public class Mathematics {

//With return type, with arguments

    public int addition (int a, int b) {
    return a+b;
    }


//Without return type, with arguments

    public void int subtraction (int a, int b){ 
   }

//Without return type , without arguments

    public void String print() {
    System.out.println(" Hello Everyone");
    }
}

The Main Method

Every Java program starts with the main method. It is the entry point for the program, and without it the code will not run.

public static void main(String[] args) {
    // program execution begins here
}

Objects in Java

Objects are instances of a class. Using objects, we can access the methods and variables defined inside a class.

Syntax:

ClassName obj name = new ClassName();

Calling Methods

Once a method is defined, we can call it using an object of the class.

public static void main (string[] args){

  Mathematics arithmetics = new Mathematics();

    System.out.println(arithmetics.addition(46,87));
}

Naming Conventions

We also learned about common naming conventions in Java:

PascalCase -> CalculatorProgram

camelCase -> simpleCalculator ( used for naming objects,methods etc...)

snake_case -> simple_calculator (lower),

upper snake case -> SIMPLE_CALCULATOR (upper)

lowercase -> simple

Consistent naming makes the code easier to read and maintain.

What I learned

In these sessions, I was able to understand:

-Different types of methods

-The role of the main method

-How objects work

-How to call methods

-Writing a simple calculator program

-Basic naming conventions

Learning Java step by step makes the language feel less intimidating, and building small programs like the calculator is a great way to practice.