1 A Tree-Structured Persistence Server for Archiving Java Run-Time States

The persistence problem of collaborative applications is a significant issue in the research of computer-supported collaborative work. A collaborative computing environment requires a simple and transparent persistence layer to deal with complex object accesses. Therefore, in this paper, we propose an object persistence mechanism and implement a persistence server, called Tree-Structured Persistence Server (TSPS), to support collaborative applications that store and retrieve application states. The server allows states of collaborative applications to be stored in a tree fashion beside tables. In addition to accommodating basic operations to access persistent objects, the TSPS offers advanced functions to manage sessions, states and versions of a collaborative application. By accessing these services, users can archive the run-time states of Java-based applications with transparency and simplicity. The TSPS was originally developed to serve as a persistence layer to support a project of computer-supported collaborative work. We intend to develop our persistence mechanism for universal use so that it can be applied in more application areas