Issues and known defects

• Line and column numbers refer to the location of the end of the XML element tag rather than the appropriate attribute. This will not be fixed.
• ARP should normally be used with the Xerces version shipping with Jena; if you need to use your own SAX parser, see the detailed instructions.
• Does not include normalizing transcoder support. This is needed for correct processing of some non-European character sets.
• There is a memory leak, see below.
• Please e-mail me with any further issues.

Memory Leak

The interaction between ARP and Xerces seems to include a significant memory leak possibly caused by Xerces interning some strings, on behalf of ARP. This feature cannot be turned off. This is not a new bug, so ARP users will not experience a degradation in performance. However, for users who have limited memory, or who are processing large files, or files from many diverse sources, or for long-lived applications such as web servers, it is important to be aware of this leak. I believe that the strings being interned correspond to the XML element tags and attribute names in the XML document. These form an open set in RDF/XML, unlike most XML applications.

A potential work around is to use a SAX parser other than Xerces and then use SAX2Model or SAX2RDF to parse the SAX event stream as RDF.

The size of the leak is presumably highly dependent on the actual RDF/XML documents read. As an example the OWL Guide wine ontology, (using the version from the OWL Test Cases) contains about 2000 triples and leaks about 180K.