Difference between revisions of "Edge Server Architecture"
From RifidiWiki
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# The runtime provides a service registry -- a system-wide repository for bundles to provide functionality. | # The runtime provides a service registry -- a system-wide repository for bundles to provide functionality. | ||
| − | In the edge server, all code is deployed as OSGi bundles. | + | In the edge server, all code is deployed as OSGi bundles, and functionality between bundles is shared by means of services that are available in the service registry. |
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==Layers== | ==Layers== | ||
===Sensor Abstraction Layer=== | ===Sensor Abstraction Layer=== | ||
Revision as of 19:19, 23 September 2009
This page describes several aspects of the Rifidi Edge Server Core. It is intended for developers to understand how the core is structured.
Contents
Overview
OSGi
OSGi is a dynamic modules system for Java. It provides several pieces of functionality including the following:
- A deployment unit (called a bundle), which is a normal JAR with some extra information in the Manifest.
- A lightweight runtime that allows bundle lifecycle to be controlled. In other words, you can start, stop, and update bundles at runtime.
- Dependencies are explicitly stated in the Manifest either as "bundle dependencies" or "package dependencies".
- Classes are only visible to other bundles if their containing packages have been exposed. This allows developers to hide classes that should be strictly internal.
- The runtime provides a service registry -- a system-wide repository for bundles to provide functionality.
In the edge server, all code is deployed as OSGi bundles, and functionality between bundles is shared by means of services that are available in the service registry.
