An incremental recovery cache supporting software fault tolerance mechanisms

This paper focuses upon the requirement to save and restore application sta te as part of the execution of error recovery mechanisms. Using the object- oriented features of the revised Ada language, we present a portable implem entation of a state recovery mechanism that is fully independent of applica tion types. Results of the implementation of this mechanism are used to hig hlight both the strengths and weaknesses of some of the object-oriented fea tures of Ada 95, particularly user-defined assignment, in the light of our equivalent implementation in C++. We then show a reusable recovery block im plementation to illustrate the use of the recovery mechanism.