@Override
public void build(
PropFuncArg argSubject, Node predicate, PropFuncArg argObject, ExecutionContext execCxt) {
super.build(argSubject, predicate, argObject, execCxt);
DatasetGraph dsg = execCxt.getDataset();
textIndex = chooseTextIndex(dsg);
if (argSubject.isList()) {
int size = argSubject.getArgListSize();
if (size != 2 && size != 3) {
throw new QueryBuildException(
"Subject has "
+ argSubject.getArgList().size()
+ " elements, not 2 or 3: "
+ argSubject);
}
}
if (argObject.isList()) {
List<Node> list = argObject.getArgList();
if (list.size() == 0) throw new QueryBuildException("Zero-length argument list");
if (list.size() > 4) throw new QueryBuildException("Too many arguments in list : " + list);
// extract of extra lang arg if present and if is usable.
// arg is removed from the list to avoid conflict with order and args length
langArg = extractArg("lang", list);
if (langArg != null && textIndex.getDocDef().getLangField() == null)
log.warn("lang argument is ignored if langField not set in the index configuration");
}
}
@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;
}