Jena UpdateFactory Parser Syntax

[Neda Alipanah <ne...@gmail.com>]

Hi everyone,
While testing history in the graph I’ve run into occasional stack overflow
when adding the Jena Model to the triplestore using an UpdateRequest.
Initially I was using Syntax.syntaxSPARQL_11 (the default for UpdateFactory)
but after googling a bit I found
http://thread.gmane.org/gmane.comp.apache.jena.user/8195 which makes me
think it is an inherent issue with the SPARQL 1.1 syntax parser and large
updates. Per the recommendation in 8195 I moved to using Syntax.syntaxARQ
which through initial testing seems to have eliminated the stack overflow.
The javadoc for syntaxARQ simply states it is *The query syntax for
extended SPARQL* which doesn’t really tell me a lot. Does anyone know the
difference between syntaxSPARQL_11 vs syntaxARQ?

Thanks
Neda

Re: Jena UpdateFactory Parser Syntax

[Andy Seaborne <an...@apache.org>]

The SPARQL 1.1 parser is exactly the spec.  In fact, the HTML and the Java
parser are built from the same source.  The grammar is LL(1) - i.e. simple
so people can implement easily.

The ARQ parser rewrites the INSERT DATA with a better, javacc specific way
to parse the same language (dynamically changing the lookahead). But it is
not applicable to simple parser generators.

https://github.com/apache/jena/blob/master/jena-arq/Grammar/master.jj#L760

    Andy

On 17 October 2017 at 10:14, Neda Alipanah <ne...@gmail.com> wrote:

> Hi everyone,
> While testing history in the graph I’ve run into occasional stack overflow
> when adding the Jena Model to the triplestore using an UpdateRequest.
> Initially I was using Syntax.syntaxSPARQL_11 (the default for
> UpdateFactory)
> but after googling a bit I found
> http://thread.gmane.org/gmane.comp.apache.jena.user/8195 which makes me
> think it is an inherent issue with the SPARQL 1.1 syntax parser and large
> updates. Per the recommendation in 8195 I moved to using Syntax.syntaxARQ
> which through initial testing seems to have eliminated the stack overflow.
> The javadoc for syntaxARQ simply states it is *The query syntax for
> extended SPARQL* which doesn’t really tell me a lot. Does anyone know the
> difference between syntaxSPARQL_11 vs syntaxARQ?
>
> Thanks
> Neda
>