Writing code is only part of a developer's job. Professional Java projects are built, versioned, and tested with a standard set of tools, and being comfortable with them is what lets you work on a team and trust your own changes.
You'll start with build tools: Maven and Gradle download dependencies, compile your code, run tests, and package your app. Then Git tracks every change and lets you collaborate through branches and pull requests. Finally you'll learn to write automated tests with JUnit 5 and isolate the code under test using mocks from Mockito.
With a project you can build, version, and test, you'll be ready for the next module, Databases, JDBC & JPA, where your code starts working with persistent data.
Installing Maven, creating a project, managing dependencies, and using it to build and package a Java application.
The core Git workflow of commits, branches, and merges, plus pushing code to GitHub.
Writing unit tests with JUnit 5, including assertions, annotations, and testing for exceptions.
What a mocking framework is for, and how to use Mockito to replace dependencies inside a unit test.