Application assembly and enterprise applications

Application assembly is the process of creating an enterprise archive (EAR) file containing all files related to an 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)
  • SAR files (known as Session Initiation Protocol (SIP) 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 Java™ archive (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 an annotation or deployment descriptor containing instructions for module deployment on the application server.

    You can use the graphical interface of Rational® Application Developer assembly tools to generate the annotation or deployment descriptor. You can also edit annotations or 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 Java Platform, Enterprise Edition (Java EE) specifications, 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 annotation or 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.