Summary  
Demonstrates how to handle exceptions in Java using try-catch blocks to catch specific exception types, printing error messages and allowing the program to continue execution.

General domain of usage  
Input validation and error handling in method calls.

# Task 

Write code to **handle exceptions** in Java using the `try-catch` structure. You will work with methods that throw **various exceptions**. Your task is to correctly handle these exceptions in the `main` method.



```python
IllegalArgumentException caught: Access denied - You must be at least 18 years old.
NullPointerException caught: String value is null.
```

>Note
>
>In this task, there **won't be any unit tests** because, later, you'll have to write them for this task **yourself**. The successful completion of this task will result in **the expected** output being displayed on the screen.

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  <li>
    Modify the <code>main</code> method to handle exceptions thrown by
    <code>checkAge</code> and <code>printLength</code>.
  </li>
  <li>Use a separate try-catch block for each method call.</li>
  <li>
    In each <code>catch</code> block, print an error message that should include
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  </li>
  <li>
    Ensure that the program continues execution after handling the exceptions.
  </li>
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package codefinity;

public class Main {
    private static final ExceptionHandlingExercise exceptionHandlingExercise
            = new ExceptionHandlingExercise();
    public static void main(String[] args) {
        try {
            exceptionHandlingExercise.checkAge(17);
        } catch (IllegalArgumentException e) {
            System.out.println("IllegalArgumentException caught: " + e.getMessage());
        }
        try {
            exceptionHandlingExercise.printLength(null);
        } catch (NullPointerException e) {
            System.out.println("NullPointerException caught: " + e.getMessage());
        }
    }
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Testing is an integral part of software development. Every module of an application should be covered by tests to ensure the correctness of a specific module or the entire application. This course will teach you about the different types of application testing. Additionally, you will practice with unit tests to test individual components of your application.

Let's talk about types of testing and which testing methods developers use. You will learn about the stages an application goes through before being delivered to the client and the specific tests you will need to write.


In this section, we're going to dive into unit testing — you'll get the rundown on its structure in Java and the ins and outs of crafting them the right way. Setting up your IDE, importing necessary libraries, and lots of hands-on practice.


In this section, we will enhance our coding skills by dealing with errors that can also be caught in unit tests. When testing an application, you may come across various errors, and sometimes they should be turned into exceptions. I will explain how to catch exceptions in your code, test them, and handle them properly.

Handling Exceptions Practice

Task