private QueryIterator variableSubject(
Binding binding, Node s, Node score, Node literal, StrMatch match, ExecutionContext execCxt) {
ListMultimap<String, TextHit> results =
query(match.getProperty(), match.getQueryString(), match.getLimit(), execCxt);
Collection<TextHit> r = results.values();
return resultsToQueryIterator(binding, s, score, literal, r, execCxt);
}
private QueryIterator concreteSubject(
Binding binding, Node s, Node score, Node literal, StrMatch match, ExecutionContext execCxt) {
if (!s.isURI()) {
log.warn("Subject not a URI: " + s);
return IterLib.noResults(execCxt);
}
String qs = match.getQueryString();
ListMultimap<String, TextHit> x =
query(match.getProperty(), match.getQueryString(), -1, execCxt);
if (x == null) // null return value - empty result
return IterLib.noResults(execCxt);
List<TextHit> r = x.get(s.getURI());
return resultsToQueryIterator(binding, s, score, literal, r, execCxt);
}
@Override
public QueryIterator exec(
Binding binding,
PropFuncArg argSubject,
Node predicate,
PropFuncArg argObject,
ExecutionContext execCxt) {
if (textIndex == null) {
if (!warningIssued) {
Log.warn(getClass(), "No text index - no text search performed");
warningIssued = true;
}
// Not a text dataset - no-op
return IterLib.result(binding, execCxt);
}
DatasetGraph dsg = execCxt.getDataset();
argSubject = Substitute.substitute(argSubject, binding);
argObject = Substitute.substitute(argObject, binding);
Node s = null;
Node score = null;
Node literal = null;
if (argSubject.isList()) {
// Length checked in build()
s = argSubject.getArg(0);
score = argSubject.getArg(1);
if (!score.isVariable())
throw new QueryExecException("Hit score is not a variable: " + argSubject);
if (argSubject.getArgListSize() > 2) {
literal = argSubject.getArg(2);
if (!literal.isVariable())
throw new QueryExecException("Hit literal is not a variable: " + argSubject);
}
} else {
s = argSubject.getArg();
}
if (s.isLiteral())
// Does not match
return IterLib.noResults(execCxt);
StrMatch match = objectToStruct(argObject, true);
if (match == null) {
// can't match
return IterLib.noResults(execCxt);
}
// ----
QueryIterator qIter =
(Var.isVar(s))
? variableSubject(binding, s, score, literal, match, execCxt)
: concreteSubject(binding, s, score, literal, match, execCxt);
if (match.getLimit() >= 0) qIter = new QueryIterSlice(qIter, 0, match.getLimit(), execCxt);
return qIter;
}