RT-OSGi: Integrating the OSGi Framework with the Real-Time Specification for Java

Abstract

The OSGi Framework, has proven ideal in developing dynamically reconfigurable Java applications based on the principles of Component-Based Software Engineering (CBSE) and Service-Oriented Architecture (SOA). One domain where OSGi has yet to make an impact is real-time systems. This is partly due to the fact that the OSGi Framework is based on standard Java, which is not suitable for developing such systems. Other reasons include the absence of various features such as temporal isolation, admission control, and a reconfigurable garbage collector (along with the associated analysis to determine the pace of garbage collection). Also, a number of features of the OSGi Framework increase the difficulty in determining the worst case execution time (WCET) of threads. This makes real-time analysis more difficult. This chapter discusses the problems associated with extending the OSGi Framework and integrating it with the Real-Time Specification for Java (RTSJ). The focus is on the design of a real-time version of the OSGi Framework (RT-OSGi) which is capable of deploying dynamically reconfigurable real-time Java applications.