Test-driven development (TDD) with JavaFX

24 Sep 2023

JavaFX

JavaFX is a popular framework for building user interfaces in Java applications. Whether you are developing a small desktop application or a complex enterprise software, it is crucial to test your code to ensure its correctness and reliability. Test-driven development (TDD) is a software development approach that promotes writing tests before writing the actual code. In this blog post, we will explore how to apply TDD principles to JavaFX development.

Setting up the project

To start with TDD in JavaFX, you need to set up your project with the necessary dependencies.

First, create a new JavaFX project in your favorite integrated development environment (IDE). Make sure you have the necessary JavaFX libraries and SDK installed.

Next, include a testing framework in your project. JUnit is a widely-used testing framework for Java applications. You can add it as a dependency using a build tool like Apache Maven or Gradle.

For Maven, add the following dependency to your pom.xml file:

<dependency>
    <groupId>org.junit.jupiter</groupId>
    <artifactId>junit-jupiter-api</artifactId>
    <version>5.8.0</version>
    <scope>test</scope>
</dependency>

For Gradle, add the following dependency to your build.gradle file:

testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.0'

Writing tests

With the necessary project setup, you can now write tests for your JavaFX application. Start by creating a test class and a test method. Annotate the test method with @Test to indicate that it is a test case.

import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.*;

public class MyJavaFXAppTest {

    @Test
    public void testAddition() {
        int result = 2 + 2;
        assertEquals(4, result);
    }
}

In the above example, we have a simple test case that verifies the addition of two numbers. The assertEquals() method compares the expected and actual values, throwing an exception if they do not match.

Running tests

To run the tests, you can execute the tests from your IDE or use a build tool like Maven or Gradle. Most IDEs have built-in support for running JUnit tests.

In IntelliJ IDEA, you can right-click on the test class or the test method and select “Run” or “Debug” to execute the tests.

Advantages of TDD with JavaFX

Applying TDD principles in your JavaFX development workflow brings several benefits:

Code reliability: Writing tests before the code helps catch bugs early and ensures the correctness of your application.
Improved design: TDD encourages you to write modular and testable code, resulting in better software architecture.
Refactoring confidence: With a comprehensive suite of tests, you can refactor your code with confidence, knowing that the tests will catch any regressions.

Conclusion

TDD is a powerful approach to developing JavaFX applications. By writing tests before writing the code, you can improve the reliability, design, and maintainability of your application. Incorporating TDD into your JavaFX projects will result in robust and high-quality software.

#JavaFX #TDD