> For the complete documentation index, see [llms.txt](https://muhammad-tri-wibowo.gitbook.io/java-tutorials/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://muhammad-tri-wibowo.gitbook.io/java-tutorials/basic-java/function.md).

# Function

In Java, functions are known as methods. A method is a block of code that performs a specific task and can be called from other parts of the program. Methods are used for code reusability and organization. Here's how you define and use methods in Java:

#### Method Declaration:

In Java, a method is declared within a class. The basic syntax of a method declaration looks like this:

```java
access_modifier return_type method_name(parameter_list) {
    // Method body
    // Code to be executed
    return value; // Return statement (if the method returns a value)
}
```

* **`access_modifier`:** Specifies the visibility of the method (`public`, `private`, `protected`, or package-private).
* **`return_type`:** Specifies the data type of the value the method returns. Use `void` if the method doesn't return any value.
* **`method_name`:** Specifies the name of the method.
* **`parameter_list`:** Specifies the parameters the method accepts (if any).
* **`return value`:** Specifies the value to be returned by the method (if applicable).

#### Example of a Method:

```java
public class Example {

    // Method that takes two integers as parameters and returns their sum
    public int addNumbers(int a, int b) {
        int sum = a + b;
        return sum;
    }

    public static void main(String[] args) {
        Example example = new Example();
        int result = example.addNumbers(5, 10);
        System.out.println("Sum: " + result);
    }
}
```

**Explanation:**

1. **`public int addNumbers(int a, int b) { ... }`:** This line declares a method named `addNumbers` with two integer parameters (`a` and `b`). The method returns an integer (`int`). Inside the method, the two parameters are added, and the sum is stored in the `sum` variable. The method then returns the `sum`.
2. **`Example example = new Example();`:** Creates an instance of the `Example` class.
3. **`int result = example.addNumbers(5, 10);`:** Calls the `addNumbers` method of the `example` object with the arguments `5` and `10`. The returned sum (`15` in this case) is stored in the `result` variable.
4. **`System.out.println("Sum: " + result);`:** Prints the result, which is `15`, to the console.

When you run this Java program, it will output:

```makefile
Sum: 15
```

This output shows the result of calling the `addNumbers` method with the arguments `5` and `10`. The method calculated the sum and returned the value `15`, which was then printed in the `main` method.