A persistent object infrastructure for heterogeneous distributed systems

A persistent object infrastructure enables applications to uniformly invoke operations on active (in-memory) and passive (stored) objects, i.e. it provides a single level object store. Objects are automatically moved between secondary storage and main memory by the infrastructure, so the impedance mismatch between the type systems of applications and the type systems of secondary storage abstractions like databases and file systems is eliminated from application programs. The paper describes a prototype of a persistent object system which has been designed for ANSA, an architecture for building heterogeneous object-based distributed systems. The prototype has been developed in ANSAware which is an example implementation of ANSA