The last topic we will learn about is molecularity and basics of  Java 9 modules. Now, we will learn how to write modules and how Dependency Injection is handled in modules.

Java 9 has the concept of Service Loader, which is related to IoC and Dependency Injection. New module systems do not provide Dependency Injection, but the same can be achieved by Service Loader and SPI (Service Provider Interface) Pattern. We will now see how this will work with Java 9.