Let's assume you are done with the steps in the previous chapter and your legacy code now complies or runs in Java 9. You are ready for the next step--to migrate your code to use Java 9 modules! What does that look like?
Here's a very high-level picture that shows the different elements of a typical pre-Java 9 application running on a Java 9 platform:
You can break a typical application down into three distinct layers. At the very top layer are the application classes and jars. Typical applications have a combination of application classes and jars along with any internal libraries, such as shared utility components. All of these are application specific. Since the application is yet to be migrated to Java 9, this layer consists of classes and jars in the classpath.
The second layer denotes any frameworks that the application might be...
