Application assembly is the process of creating an enterprise
archive (EAR) file containing all files related to an application,
as well as an XML deployment descriptor for the application. This
configuration and packaging prepares the application for deployment
onto an application server.
EAR files are comprised of the following archives:
- Enterprise bean JAR files (known as EJB modules)
- Web archive (WAR) files (known as Web modules)
- Application client JAR files (known as client modules)
- Resource adapter archive (RAR) files (known as resource adapter
modules)
Ensure that modules are contained in an EAR file so that they can
be deployed onto the server. The exceptions are WAR modules, which
you can deploy individually. Although WAR modules can contain regular
JAR files, they cannot contain the other module types described previously.
The assembly process includes the following actions:
- Selecting all of the files to include in the module.
- Creating a deployment descriptor containing instructions for module
deployment on the application server.
As you configure properties using
an assembly tool,
the tool generates the deployment descriptor for you. While the Application
Server Toolkit, Rational Application Developer or Rational Web Developer
graphical interface is recommended, you can also edit descriptors directly in
your favorite XML editor.
- Packaging modules into a single EAR file, which contains one or
more files in a compressed format.
As part of the assembly process, you might also set environment-specific
binding information. These bindings are defaults for an administrator
to use when installing the application through the administrative
console. Further, you might define IBM extensions to the J2EE specification,
such as to allow servlets to be served by class name. To ensure portability
to other application servers, these extensions are saved in an XML
file that is separate from the standard J2EE deployment descriptor.
Restriction: Do not include a pound sign
(#) in the name of files that are packaged within an application archive.
Due to internal processing, the application server fails to correctly
deploy the application when a pound sign is included in a file name
within the application archive. When this failure occurs, an exception
might occur when the application is being processed. Also, parts of
the application might be missing after the application is deployed.
To address this issue, rename any file names within the application
archive so that they do not contain a pound sign.