• Felix -- is a community implementation of the OSGi Release 4.x under the Apache Foundation. It is designed particularly for compactnes and ease of embedding, and is the smallest of the Release 4 implementations.
• Equinox -- is the most widely deployed OSGi framework today owing to its use in the core runtime of Eclipse. It can also be found in many in-house custom applications as well as packaged products such as Lotus Notes and IBM WebSphere? Application Server. Equinox implements Release 4.1 of the OSGi specifications.
• Knopflerfish -- is a popular and mature implementation of both OSGi Release 3 and Release 4.1 specifications. It is developed and maintained by Makewave, a company based in Sweden, and is licensed under a BSD-style license.
• Concierge -- is a very compact and highly optimized implementation of OSGi Release 3. This makes it particularly suited to resource-constrained platforms such as mobile phones.

OSGi Overview

OSGi is a module system for Java that implements a dynamic component model. Applications demodularized into components can be installed, started, stopped, updated and uninstalled without requiring stopping of JVM.

Components are called bundles and they are based on the common jar file format. This format is extended to be able to desribe dependencies between bundles.

OSGi Class Loaders

The most valuable feature of OSGi, which led to expansions of OSGi, is the principle of module class loaders. On the contrary to basic Java class loading system in OSGi all resolved bundles have theirs own class loader. It helps to create encapsulated modules with defined dependencies.

OSGi Players

OSGi technology was developed by OSGi Alliance. It is defined by OSGi Specification and implemented by OSGi framework. Several independently implemented OSGi frameworks exist today, including four that are available as open source software.

    * Felix -- is a community implementation of the OSGi Release 4.x under the Apache Foundation. It is designed particularly for compactnes and ease of embedding, and is the smallest of the Release 4 implementations.
    * Equinox -- is the most widely deployed OSGi framework today owing to its use in the core runtime of Eclipse. It can also be found in many in-house custom applications as well as packaged products such as Lotus Notes and IBM WebSphere? Application Server. Equinox implements Release 4.1 of the OSGi specifications.
    * Knopflerfish -- is a popular and mature implementation of both OSGi Release 3 and Release 4.1 specifications. It is developed and maintained by Makewave, a company based in Sweden, and is licensed under a BSD-style license.
    * Concierge -- is a very compact and highly optimized implementation of OSGi Release 3. This makes it particularly suited to resource-constrained platforms such as mobile phones.

Osgi framework

Tutoriál na vytvoření nového projektu a HelloWorld. Výsledná implementace: Attach:HelloWorldOsgi

Tutoriál na vytvoření nového projektu a HelloWorld? HelloWorldOsgi. Výsledná implementace: Attach:HelloWorldOsgi

== Osgi framework ==

V těchto návodech pracuji s SpringSource Tool Suite, které je trochu odlišné od Eclipsu. Většina věcí je však stejná.

Tutoriál na vytvoření nového projektu a HelloWorld? HelloWorldOsgi. Výsledná implementace: Attach:HelloOsgi Δ

Příklad MessagePrinterOsgi pak dokumentuje jen technologicky specifické problémy. Výsledná implementace: Attach:MessagePrinterOsgi

Příklad ParkovisteOsgi pak dokumentuje jen technologicky specifické problémy. Výsledná implementace: Attach:ParkovisteOsgi