Research And Application Of Embedded Software Component Extraction And Composition

The component-based software development methodology can build software systems effectively with a high reliability by means of the construction and composition of the reusable software components.In recent years,due to the widespread use of more powerful hardware in embedded systems,the size and complexity of embedded software are increasing rapidly,and the embedded software has been regarded as one of the most predominant factors influencing the functionality and quality of the whole system.Since embedded system is generally composed of some interactive subsystems,the embedded software system shows more component-based features than those of general software systems,and it is feasible to apply component-based method to the process of embedded software development.Component-based embedded software development isn't mature yet and the research in this field distributes widely in the development process.Based on entire-station instrument software system project and some widely used embedded operating system,this paper does research and application in embedded software component technology.The contents of this paper list as follows.Firstly,research on embedded software component in point of theory view.This paper shows the embedded software special features in component definition,component model and component description,and explains the research contents based on process of component-based software development.Secondly,research on embedded software component extraction.By researching on legacy project and reverse engineering,this paper proposes an extraction process that is suitable for embedded software.The extraction process which adopts both top-down and bottom-up method to extract component comprises system decomposition,model construction,realization hierarchically,and performance measurement.The process is described in detail by an experiment,which is GUI component extraction fromμC/OS-Ⅱand reusing in uClinux.Thirdly,we do research on embedded software component composition.Based on understanding of classification of current composition technology,this paper applies architecture-based component composition to embedded software development,realizes the composition in source code level giving consideration to real-time constraints and resource restrictions,and at last,elaborates the composition process by an experiment of a media player in WINCE system.