In this chapter, we've studied the differences between unit and integration tests.

We saw how testing is a healthy habit that will give us confidence in what we build and what we ship. It will save us money and spare some headaches in the long run.

Spring works well with classical JUnit tests written in Java, and it has first-class support for integration tests. But we can also easily use other languages, such as Groovy, to make the tests more readable and easier to write.

Testing is undeniably one of the strongest points of the Spring framework and one of the main reasons to use dependency injection in the first place.

Stay tuned for the next chapter, where we will optimize our application so that it is ready to be deployed in the cloud!