Understanding Methods in Java with Simple Example

What is a Method in Java?

A method in Java is a block of code that performs a specific task.
It helps you reuse code, improve readability, and organize programs.

Basic Syntax

returnType methodName(parameters) {
    // method body
    // code to execute
    return value; // optional
}

Example Program

public class Calculator{
    public static void main(String[] args){
        Calculator casio = new Calculator();
        casio.add(10,5);
        casio.sub(10,5);
        casio.multiply(10,5);
        casio.div(10,5);
    }
    void add(int a,int b){
        System.out.println(a+b);
    }
    void sub(int a,int b){
        System.out.println(a-b);
    }
    void multiply(int a,int b){
        System.out.println(a*b);
    }
    void div(int a,int b){
        System.out.println(a/b);
    }
}

Output

Flow of Execution

1. Program starts in main()
2. Object casio is created
3. Methods are called one by one:
   • add() → prints 15
   • sub() → prints 5
   • multiply() → prints 50
   • div() → prints 2
4. Program ends

Types of Methods in Java
1. Predefined Methods

These are already available in Java libraries.

Example:

System.out.println("Hello");

Here, println() is a predefined method.

2. User-defined Methods

Methods created by the programmer.

Example:

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