@Override
public int write(TupleIterator iter) throws TrippiException {
try {
m_out.println("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
doEntities();
m_out.println("<sparql xmlns=\"http://www.w3.org/2001/sw/DataAccess/rf1/result\">");
String[] names = iter.names();
m_out.println(" <head>");
for (int i = 0; i < names.length; i++) {
m_out.println(" <variable name=\"" + names[i] + "\"/>");
}
m_out.println(" </head>");
m_out.println(" <results>");
int count = 0;
while (iter.hasNext()) {
m_out.println(" <result>");
Map<String, Node> result = iter.next();
for (int i = 0; i < names.length; i++) {
m_out.print(" <" + names[i]);
Node n = result.get(names[i]);
if (n == null) {
m_out.println(" bound=\"false\"/>");
} else if (n instanceof URIReference) {
String uriString = ((URIReference) n).getURI().toString();
m_out.println(" uri=\"" + getURI(uriString) + "\"/>");
} else if (n instanceof BlankNode) {
String id = "blank" + n.hashCode();
m_out.println(" bnodeid=\"" + id + "\"/>");
} else if (n instanceof Literal) {
Literal lit = (Literal) n;
URI dType = lit.getDatatypeURI();
if (dType != null) {
m_out.print(" datatype=\"" + getURI(dType.toString()) + "\"");
}
String lang = lit.getLanguage();
if (lang != null) {
m_out.print(" xml:lang=\"" + lang + "\"");
}
m_out.println(">" + enc(lit.getLexicalForm()) + "</" + names[i] + ">");
} else {
throw new TrippiException("Unrecognized node type: " + n.getClass().getName());
}
}
m_out.println(" </result>");
m_out.flush();
count++;
}
m_out.println(" </results>");
m_out.println("</sparql>");
m_out.flush();
iter.close();
return count;
} catch (IOException e) {
throw new TrippiException("Error writing", e);
}
}
/**
* Convert a Mulgara Value to a Jena graph node.
*
* @param obj The Mulgara value to convert.
* @return A new Jena graph node.
*/
static Node o2n(org.jrdf.graph.Node obj) {
if (obj == null) return Node.ANY;
// testing for org.jrdf.graph.URIReference
if (obj.isURIReference()) {
URIReference uRef = (URIReference) obj;
if (skolemizedBlankNodes) {
String x = uRef.getURI().toString();
if (x.startsWith(bNodeScheme)) {
x = x.substring(bNodeScheme.length());
Node n = Node.createAnon(new AnonId(x));
return n;
}
}
return Node.createURI(uRef.getURI().toString());
}
// testing for org.jrdf.graph.Literal
if (obj.isLiteral()) {
Literal literal = (Literal) obj;
if (literal.getDatatypeURI() != null) {
RDFDatatype type =
TypeMapper.getInstance().getSafeTypeByName(literal.getDatatypeURI().toString());
return Node.createLiteral(literal.getLexicalForm(), null, type);
}
return Node.createLiteral(literal.getLexicalForm(), literal.getLanguage(), null);
}
if (obj.isBlankNode()) {
BlankNodeImpl b = (BlankNodeImpl) obj;
// check if this was a Jena-allocated node
Node jenaNode = valuesToNodes.get(b);
// if not known, then create a Jena node from the Mulgara ID
return jenaNode != null ? jenaNode : Node.createAnon(new AnonId(b.getID()));
}
throw new RuntimeException("Can't convert to Jena Node : " + obj);
}
/**
* Used to write Resources for a Subject. Resources will use "ObjectNode" method.
*
* @param predicate PredicateNode
* @param object Literal
* @param writer PrintWriter
* @throws GraphException
*/
protected void writeStatement(
Graph graph, SubjectNode subject, PredicateNode predicate, Literal object, PrintWriter writer)
throws GraphException {
// determine if the Literal has a datatype
URI datatype = object.getDatatypeURI();
// Get the lexical form of the literal
String literalObject = object.getLexicalForm();
// Create the StringBuffer to hold the resultant string
StringBuffer buffer = new StringBuffer();
// Escape the XML string
StringUtil.quoteAV(literalObject, buffer);
if (datatype != null) {
// write as: <predicateURI rdf:datatype="datatype">"Literal value"
// </predicateURI>
writer.println(
" <"
+ this.getURI(predicate)
+ " "
+ RDF_PREFIX
+ ":datatype=\""
+ datatype
+ "\">"
+ buffer.toString()
+ "</"
+ this.getURI(predicate)
+ ">");
} else {
// write as: <predicateURI>"Literal value"</predicateURI>
writer.println(
" <"
+ this.getURI(predicate)
+ ">"
+ buffer.toString()
+ "</"
+ this.getURI(predicate)
+ ">");
}
}