2010, Graf, Sebastian, Lewandowski, Lukas, Grün, Christian

REST nowadays represents, besides SOAP, one common way to access distributed resources in a web-affine manner. While SOAP can be easily utilized by high-level programming languages like Java (e.g. JAX-WS as one common standardized way), REST catches up regarding straight usages (e.g JAX-RS regarding Java).
With the clean and direct usage of JAX-RS, common layers for standardised access on heterogeneous XML-resources can be defined. This is what the project JAX-RX stands for: Based on XML as modern resource in the WWW, we defined a common application programming interface to access Java enabled XML resource easily in a common way. Using a common architecture for the uniform resource locator on the one hand and defining suitable interfaces on the other hand, every XML generating resources can be \RESTified\ with nearly no effort. This technical report describes the motivation, the architecture and the usage of our XML-enabling API called JAX-RX.

2010, Graf, Sebastian, Lewandowski, Lukas, Waldvogel, Marcel

The REpresentational State Transfer (REST) represents an extensible, easy and elegant architecture for accessing web-based re- sources. REST alone and in combination with XML is fast gaining mo- mentum in a diverse set of web applications. REST is stateless, as is HTTP on which it is built. For many applications, this not enough, es- pecially in the context of concurrent access and the increasing need for auditing and accountability. We present a lightweight mechanism which allows the application to control the integrity of the underlying resources in a simple, yet flexible manner. Based on an opportunistic locking ap- proach, we show in this paper that XML does not only act as an exten- sible and direct accessible backend that ensures easy modifications due to the allocation of nodes, but also gives scalable possibilities to perform on-the-fly integrity verification based on the tree structure.

2009, Graf, Sebastian

TreeTank is an easy-to-use framework which allows users to store, modify and retrieve tree-structured data. Modifications are encapsulated in different revisions which supports a navigation not only in the data-structure but also in the time-axis. Despite being an active research project, the software is covered with automatic test-cases and is used as a base for multiple student-projects and their thesis. TreeTank comes as a light-weight java program which allows easy handling in any java environment.
This report gives a short overview over the motivation, the technical foundation and projects based on with cited papers and an outlook in further extensions.