Testing is an essential part of any development. Unit testing tests a class in isolation and external dependencies should be minimized. You can consider creating stubs or mocks to unit test. You don't need Spring to unit test. Integration testing tests the interaction of multiple units working together. Spring provides good integration testing support and profiles for different test and deployment configurations.

There are many tools available to test services such as Postman and SoapUI. In this chapter, we saw how to use Postman to test RESTful services. Postman provides support for all HTTP methods with every content type.

In the next chapter, we will explore the Docker container and will create Docker images.