public static void addConstantConstraint(Map<Var, NodeValue> map, Var var, NodeValue nodeValue) {
if (map.containsKey(var)) {
NodeValue oldValue = map.get(var);
if (oldValue != null && !oldValue.equals(nodeValue)) {
map.put(var, null);
}
} else {
map.put(var, nodeValue);
}
}
/*
* See http://www.w3.org/TR/rdf-sparql-query paragraph 11.4.12
*
* "(LANGMATCHES) returns true if language-tag (first argument) matches language-range (second argument)
* per the basic filtering scheme defined in [RFC4647] section 3.3.1. language-range is a basic language
* range per Matching of Language Tags [RFC4647] section 2.1. A language-range of "*" matches any non-empty
* language-tag string."
*
* @see http://www.w3.org/TR/rdf-sparql-query
*/
private void convertLangMatches(E_LangMatches expr) {
logger.debug("convertLangMatches " + expr.toString());
expr.getArg1().visit(this);
expr.getArg2().visit(this);
Expression e2 = expression.pop();
Expression e1 = expression.pop();
if (e1 instanceof ConstantEx && e2 instanceof ConstantEx) {
ConstantEx lang1 = (ConstantEx) e1;
ConstantEx lang2 = (ConstantEx) e2;
NodeValue nv1 = NodeValue.makeString(lang1.getNode().getLiteral().getLexicalForm());
NodeValue nv2 = NodeValue.makeString(lang2.getNode().getLiteral().getLexicalForm());
NodeValue match = NodeFunctions.langMatches(nv1, nv2);
expression.push(match.equals(NodeValue.TRUE) ? Expression.TRUE : Expression.FALSE);
} else {
expression.push(Expression.FALSE);
}
}