Apache reconfigures Geronimo to OSGi base to aid Java developers

Apache Software Foundation has reconfigured its Geronimo application server to a set of standards established by the OSGi Alliance (Open Services Gateway initiative) in an attempt to help developers create more modular enterprise Java programs.

An application server based on the OSGi standard "is a lot more dynamic and provides a lot more structure to the developers," said Kevan Miller, chairman of the Geronimo Project management committee.

Apache has released the first beta of Geronimo version 3, which it expects to ship in finalised form early next year, Miller said.

The open source software will deploy the OSGi programmer model, which should help organisations more easily deploy and modify large enterprise Java-based systems. It also uses the OSGI kernel for its runtime operations.

OSGi Alliance

With this move, Geronimo will be joining Oracle's Glassfish, Red Hat's JBoss and IBM WebSphere in their use of OSGi specs.

The OSGi Alliance, originally just called OSGi, developed a set of standards for breaking large Java programs into individual components, called bundles, so they can be managed more easily. A bundle is a Java JAR (Java Archive) that executes some specific functionality, along with a metadata file that specifies, a machine readable format, the required dependencies and configuration settings.

"Many larger enterprises have very large Java applications, and in order to be more agile and respond more quickly to changing requirements, they need to componentise their enterprise applications," Miller explained. By supporting the OSGi programming model, Geronimo will allow programmers to build and maintain modular enterprise applications. They can add a new bundle to the application, or update an existing one, and the system will detect the presence of the new component and incorporate its functionality automatically.

OSGi kernel

In addition to offering the OSGi programming model, Geronimo 3.0 will also run on an OSGi kernel. It will handle duties such as class loading, dependency management, and versioning of classes and objects in an way specified by OSGi. "OSGi gave us a mechanism that allowed us to move from a one-off system specific to Geronimo to a more standardised system," Miller said. Someone familiar with OSGi from another application server, such as Glassfish, will be familiar with Geronimo's new environment, Miller said.

In addition to OSGi support, Geronimo 3.0 will be the first version of the app server to support the latest version of the Java Enterprise Edition standard, Java EE 6. It embodies both the full implementation of Java EE 6, as well as the Java Web Profile, a subset of features for running web applications.

Apache is currently considering managing the Flash-based Flex framework after Adobe submitted its code to the ASF to take control of Flex as an independent project.