Ok thanks.
On Wed, Jul 20, 2011 at 3:21 PM, Andy Seaborne <[email protected]> wrote: > You could use: > > myMethod(((Number)getLiteralValue()).longValue()) > > which will get auto-boxed to Long. > > Andy > > > > > On 20/07/11 13:44, Laurent Pellegrino wrote: >> >> Ok, the operation i am trying to perform is: >> >> myMethod((Long) quad.getObject().getLiteralValue()) >> >> where the method signature is: >> >> public void myMethod(Long value); >> >> and where the initial value inserted as a typed literal was declared >> as xsd:long. >> >> One of the solution I have found is: >> >> myMethod(Long.parseLong(quad.getObject().getLiteralLexicalForm())) >> >> I have understood that Jena returns an Integer because the value fit >> into a 32 bits value but the literal was created and tagged with a >> xsd:Long (which is defined as a signed 64-bit integer) that's why I >> expect to get a Java Long when I call >> quad.getObject().getLiteralValue(). Even if the value can fit in a >> Java Integer. >> >> Laurent >> >> On Wed, Jul 20, 2011 at 2:27 PM, Andy Seaborne >> <[email protected]> wrote: >>> >>> >>> On 20/07/11 13:15, Laurent Pellegrino wrote: >>>> >>>> Just to fix a mistake in my previous message : Long are 64 bits and not >>>> 128. >>>> >>>> On Wed, Jul 20, 2011 at 2:02 PM, Laurent Pellegrino >>>> <[email protected]> wrote: >>>>> >>>>> Thanks for your explanations. However, my problem is that >>>>> node.getLiteralValue() on the node returns an Integer Java object. >>>>> >>>>> DatasetGraphTDB dataset = TDBFactory.createDatasetGraph(); >>>>> >>>>> dataset.add(new Quad( >>>>> Node.createURI("http://openjena.org";), >>>>> Node.createURI("http://openjena.org";), >>>>> Node.createURI("http://openjena.org";), >>>>> Node.createLiteral( >>>>> "-628675214", null, XSDDatatype.XSDlong))); >>>>> >>>>> Iterator<Quad> res = >>>>> dataset.findNG(Node.ANY, Node.ANY, Node.ANY, Node.ANY); >>>>> >>>>> Quad quad = null; >>>>> while (res.hasNext()) { >>>>> quad = res.next(); >>>>> >>>>> System.out.println(quad.getObject().getLiteralValue().getClass()); >>>>> } >>>>> >>>>> dataset.close(); >>>>> >>>>> It prints: >>>>> class java.lang.Integer >>>>> >>>>> Or the problem is that I use quad.getObject().getLiteralValue() as a >>>>> parameter of a method that expects a Java Long object because the >>>>> value that was initially stored was a Long: >>>>> >>>>> myMethod((Long) quad.getObject().getLiteralValue()) >>>>> >>>>> Or I get a ClassCastException due to the fact that >>>>> quad.getObject().getLiteralValue() returns an Integer. >>> >>> because the value (-628675214) can be fitted into an Java Integer. It's >>> just a class choosen because it can represent the value. Ditto xsd:byte. >>> >>> >>> >>>>> Indeed, it is not possible to store a full Long (128 bits) as a typed >>>>> literal (due to the fact that numbers are encoded into 56 bits). >>> >>> If it does not fit in 56 bits, then TDB stores the thing in the long >>> form. >>> 56 bits is not a limitation on the values that can be stored - its the >>> limit on what can be stored compactly. If it does not fit, TDB falls >>> back >>> on storing the lexical form and type. >>> >>>>> Hence, I have to store it as a non-typed literal and to parse it >>>>> manually but it also means that I cannot apply any method specific to >>>>> numbers on that field from a SPARQL query. That's why I was thinking >>>>> it is an issue :( >>> >>> You should be able to >>> >>> class Integer extends Number >>> Number.longValue() >>> >>> What operation are you wishing to perform? >>> >>> Andy >>> >>>>> >>>>> Laurent >>>>> >>>>> On Wed, Jul 20, 2011 at 11:45 AM, Andy Seaborne >>>>> <[email protected]> wrote: >>>>>> >>>>>> >>>>>> On 19/07/11 14:56, Laurent Pellegrino wrote: >>>>>>> >>>>>>> Hi all, >>>>>>> >>>>>>> I am currently using a TDB instance with Quadruples >>>>>>> (DatasetGraphTDB). >>>>>>> I insert some quads with a literal value which is typed with >>>>>>> xsd:long: >>>>>>> >>>>>>> Node.createLiteral(Long.toString(myIdWhichIsAJavaLong), null, >>>>>>> XSDDatatype.XSDlong) >>>>>>> >>>>>>> At this step if I print the content to the standard output I get >>>>>>> something >>>>>>> like: >>>>>>> "1900023546"^^http://www.w3.org/2001/XMLSchema#long >>>>>>> >>>>>>> Then, I execute a query that return the quadruples that contain the >>>>>>> literal values that were initially typed as xsd:long. When I print >>>>>>> the >>>>>>> content to the standard output I get: >>>>>>> "1900023546"^^http://www.w3.org/2001/XMLSchema#integer >>>>>>> >>>>>>> Why does the datatype is not the same? Is it an issue? >>>>>> >>>>>> No - or at least, it shouldn't. >>>>>> >>>>>> xsd:long is a XSD 64 bit number >>>>>> xsd:integer is an arbitrary precision >>>>>> >>>>>> xsd:integer is a more general datatype than xsd:long (xsd:int is the >>>>>> 32 >>>>>> bit >>>>>> XSD integer). >>>>>> >>>>>> TDB stores numbers (integers, decimals, doubles), and dates and >>>>>> dateTimes >>>>>> and booleans, as their value, not as their lexical form. Actually, it >>>>>> encodes them into 56 bits (currently). If the number does not fit it >>>>>> is >>>>>> stores via the node table and lexical form. >>>>>> >>>>>> This saves space and makes queries involving FILTERs on values go >>>>>> faster. >>>>>> Much faster. >>>>>> >>>>>> See NodeId.inline(Node) >>>>>> >>>>>> Andy >>>>>> >>>>> >>> >
