Application-Specific Class Loading

You can specify module- or application-specific library classes during deployment in one of the following ways:

• Use the Administration Console. Open the Applications component, then go to the page for the type of application or module. Select the Deploy button. Type the comma-separated paths in the Libraries field. For details, click the Help button in the Administration Console.

• Use the asadmin deploy command with the ----libraries option and specify comma-separated paths. For details, see the Oracle GlassFish Server 3.0.1 Reference Manual.

The Libraries field in the Administration Console's deployment page and the ----libraries option of the asadmin deploy command do not apply to application clients. For more information, see Using Libraries with Application Clients.

You can only specify module- or application-specific library classes during deployment. You can update a library JAR file using dynamic reloading or by restarting (disabling and re-enabling) a module or application. To add or remove library JAR files, you must redeploy the module or application.

Application libraries are included in the Applib class loader. Paths to libraries can be relative or absolute. A relative path is relative to domain-dir/lib/applibs. If the path is absolute, the path must be accessible to the domain administration server (DAS).

You can use application-specific class loading to specify a different XML parser than the default GlassFish Server XML parser. For details, see http://blogs.sun.com/sivakumart/entry/classloaders_in_glassfish_an_attempt.

You can also use application-specific class loading to access different versions of a library from different applications.

If multiple applications or modules refer to the same libraries, classes in those libraries are automatically shared. This can reduce the memory footprint and allow sharing of static information. However, applications or modules using application-specific libraries are not portable. Other ways to make libraries available are described in Circumventing Class Loader Isolation.

One library cannot reference classes from another library.

For general information about deployment, including dynamic reloading, see the Oracle GlassFish Server 3.0.1 Application Deployment Guide.

If you see an access control error message when you try to use a library, you may need to grant permission to the library in the server.policy file. For more information, see Changing Permissions for an Application.