Use directory deployment only to deploy to the default server instance (server). You cannot use it to deploy to clusters or stand-alone server instances.
A directory containing an unpackaged application or module is sometimes called an exploded directory. The contents of the directory must match the contents of a corresponding J2EE archive file. For example, if you deploy a Web application from a directory, the contents of the directory must be the same as a corresponding WAR file. For information about the required directory contents, see the appropriate specifications.
You can change the deployment descriptor files directly in the exploded directory.
If your environment is configured to use dynamic reloading, you can also dynamically reload applications deployed from the directory. For more information, see Configuring Advanced Settings.