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OSGi has been a solid part of the Java ecosystem for years, but it’s still a much-talked about technology, with the OSGi Alliance releasing the Core 4.3 specification just last month, and a host of new OSGi projects such as Libra in the Eclipse ecosystem, and the Pojo Service Registry project (which has been referred to as “OSGi-lite”) ensuring OSGi remains in the spotlight. The OSGi framework was introduced as a module system and service platform, as part of an attempt to standardise module deployments for Java. Frameworks that implement the OSGi standard achieve application lifecycle management via APIs, and components and applications can be remotely installed, started, updated, stopped and uninstalled without rebooting. Originally focusing on service gateways (the OSGi Alliance’s original moniker was the Open Services Gateway initiative) the OSGi specification have increasingly pushed the technology into new areas, as seen in the formation of the OSGi Alliance’s Mobile Expert Group in October 2003, and the Enterprise Expert Group, which addresses Enterprise/Server-side applications. Despite many successes (not least when Eclipse settled on OSGi for the underlying runtime of the plugin architecture used for the Eclipse RCP and IDE platform) two questions have dogged OSGi throughout: is OSGi too complex, and is it ready for the enterprise? Some argue that instead of simplifying server application development, OSGi has actually made it more complex, and the readiness of OSGi for enterprise applications has been another area of contention. Those who see a place for OSGi in the enterprise point to examples of vendors such as IBM building OSGi into their products, while those who believe OSGi isn’t ready for the enterprise, use examples such as SpringSource donating dm Server to the Eclipse foundation, as proof that OSGi-based technologies don’t always enjoy a healthy adoption rate in an enterprise environment. Despite these two on-going debates, currently, a complete and dynamic component model does not exist in standalone Java environments - meaning that OSGi is in no danger of losing its spot in the Java ecosystem anytime soon. In this issue of Java Tech Journal, we deep dive into OSGi, with two articles that examine the controversial issue of OSGi’s place in the enterprise, a look at the latest OSGi specification, a tour through some OSGi projects you may not have heard of, and lots more OSGi-related goodness. Happy reading!