Application extension registry
WebSphere® Application Server has enabled the Eclipse extension framework for applications to use. Applications are extensible when they contain a defined extension point and provide the extension processing code for the extensible area of the application.
The architecture of extensible Java EE applications follow a modular design to add new functional modules or to replace an existing module, particularly by those outside of its core development team. Each module is a pluggable unit, or plug-in that is either deployed into the portal or removed from the Java EE application using a deployment tool that is based upon standard Java EE and portal web module deployment tooling. A plug-in module describes where it is extensible and what capability it provides to other plug-ins in the plugin.xml file. The plugin.xml manifest file can be created with a simple text editor or in Eclipse's Plug-in Development Environment (PDE), which provides a simplified view of the same underlying XML data.
WebSphere Application Server implementations to the Eclipse model
- Implementing all of the extension registry-related interfaces from Eclipse 3.6 and later.
- The identical plugin.xml syntax, however, some attributes are not used, for example, <runtime>.
- The discovery and addition of plug-ins to the registry, when the containing Java EE module starts, and plug-ins are dismissed and removed from the registry when the containing Java EE module stops.
- Access to an IExtensionRegistry object is through the Java Naming and Directory Interface (JNDI), instead of by using the Platform.getExtensionRegistry method in the Eclipse Workbench.
- Filtering capability is available by providing a filter implementation and using a named registry instance that finds and invokes the filter as necessary. See the developer API documentation for the IExtensionRegistryFilter interface for more details.
Available Eclipse 3.6 interfaces
The following Eclipse 3.6 and later interfaces are available on WebSphere Application Server:
- Extension registry API
- Extension point API
- Extension API
- Configuration element API
- Registry change listener API
- Registry change event API
- Extension delta API
- Status API
- Executable extension API
- Executable extension factory API