Modular Design

In Sun GlassFish Enterprise Server v3, the GlassFish code was split into modules to provide flexibility and improved runtime performance. The modular architecture is implemented on top of OSGi Alliance standards and enables reusability of Enterprise Server v3 modules as well as other modules.

This design change allows use of only those modules that you require for the applications deployed. Runtime is used only for applications that use it, and upgrades can be implemented without a complete system reinstallation. This change minimizes startup times, memory consumption, and disk space requirements.

The modular design provides the ability to do the following:

• Deploy OSGi bundles

• Deploy library Java archive (JAR) files

• Replace existing functionality with another implementation