The AS 7 filesystem

The difference between standalone and domain reflects in the filesystem of the application server, as shown in the following diagram:

As you can see, the AS 7 filesystem is divided into two main parts: the first one is pertinent to a standalone server mode and the other is dedicated to a domain server mode. Common to both server modes is the modules directory, which is the heart of the application server.

JBoss AS 7 is based on the JBoss Modules project, which provides an implementation of a modular (non-hierarchical) class loading and execution environment for Java. In other words, rather than a single class loader that loads all JARs into a flat class path, each library becomes a module, which only links against the exact modules it depends on and nothing more. It implements a thread-safe, fast, and highly concurrent delegating class loader model, coupled with an extensible module resolution system, which combine to form a unique, simple, and powerful system for application execution and distribution.

The following table details the content of each folder contained at the root of JBOSS_HOME:

Digging into the standalone server tree, we can find folders that are pertinent to standalone independent processes. If you have experience on earlier server releases, you will find these folders quite intuitive to you:

The domain directory structure is quite similar to the standalone equivalent, with one important difference: as you can see from the following table, the deployments folder is not present here since the domain mode does not support deploying content based on scanning a filesystem. We need to use the JBoss AS 7 managed instruments (CLI and Web Admin console) in order to deploy applications to a domain.