Permanent Storage Development for the J2EE Public Service at CERN

This Master thesis develops two solutions enabling permanent file storage for the J2EE Public Service at CERN by the use of Slide, a Java implementation of the IETF WebDAV protocol for distributed authoring and versioning. Permanent storage development has been a requested feature for the J2EE Public Service since the startup in 2005, and in this thesis two libraries are investigated concerning how well they suit the J2EE Public Service environment, namely Jakarta Slide and Jakarta VFS. After research and test implementations, it is found that Slide performs well enough to be used in the future development of such a feature, while VFS does not because of adaption problems to the CERN environment. On the basis of the research, two different solutions are implemented. The first solution is a stand-alone class that can be used for simple file/retrieval by providing specific methods for use by web application authors. After evaluation, this library is found to have several problems, especially concerning the missing transparency for the authors and no support for file hierarchy. The final solution is for this reason a re-implementation of the classes in Java that deals with file I/O, which provides a transparent and secure way of doing retrieval and storage from the J2EE Public Service.