In the previous chapters, we explored the interop experience between Java and Kotlin. We've examined some of the pain points and saw how we can improve the interop experience through the use of things such as annotations and companion objects. Understanding where your code base's interop experience can be improved relies heavily on actually using APIs from different languages.
Using your APIs is typically dependent on whatever task you're currently working on, and it might not make sense to exercise a particular Kotlin API from Java, or vice versa. This is where testing can be really useful. We can make an explicit effort to write tests that explore how our code works from one language to the next.
In this section, we'll explore how we can improve the interop experience in our code base through writing tests.
