private QueryIterator resultsToQueryIterator(
Binding binding,
Node s,
Node score,
Node literal,
Collection<TextHit> results,
ExecutionContext execCxt) {
Var sVar = Var.isVar(s) ? Var.alloc(s) : null;
Var scoreVar = (score == null) ? null : Var.alloc(score);
Var literalVar = (literal == null) ? null : Var.alloc(literal);
Function<TextHit, Binding> converter =
(TextHit hit) -> {
if (score == null && literal == null)
return sVar != null
? BindingFactory.binding(binding, sVar, hit.getNode())
: BindingFactory.binding(binding);
BindingMap bmap = BindingFactory.create(binding);
if (sVar != null) bmap.add(sVar, hit.getNode());
if (scoreVar != null) bmap.add(scoreVar, NodeFactoryExtra.floatToNode(hit.getScore()));
if (literalVar != null) bmap.add(literalVar, hit.getLiteral());
return bmap;
};
Iterator<Binding> bIter = Iter.map(results.iterator(), converter);
QueryIterator qIter = new QueryIterPlainWrapper(bIter, execCxt);
return qIter;
}
/**
* Tests whether an algebra expression gives the same results when run both with and without a
* given optimizer
*
* @param algStr Algebra
* @param ds Dataset
* @param opt Optimizer
* @param expected Expected number of results
*/
public static void testAsAlgebra(String algStr, Dataset ds, Symbol opt, int expected) {
Op op = SSE.parseOp(algStr);
List<String> vars = new ArrayList<>();
for (Var v : OpVars.visibleVars(op)) {
vars.add(v.getName());
}
// Track current state
boolean isEnabled = ARQ.isTrue(opt);
boolean isDisabled = ARQ.isFalse(opt);
try {
// Run first without optimization
ARQ.set(opt, false);
QueryEngineMain engine =
new QueryEngineMain(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
QueryIterator iter =
engine.eval(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
ResultSetRewindable rs =
ResultSetFactory.makeRewindable(
new ResultSetStream(vars, ModelFactory.createDefaultModel(), iter));
if (expected != rs.size()) {
System.err.println("Non-optimized results not as expected");
TextOutput output = new TextOutput((SerializationContext) null);
output.format(System.out, rs);
rs.reset();
}
Assert.assertEquals(expected, rs.size());
iter.close();
// Run with optimization
ARQ.set(opt, true);
engine =
new QueryEngineMain(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
QueryIterator iterOpt =
engine.eval(op, ds.asDatasetGraph(), BindingFactory.binding(), ARQ.getContext());
ResultSetRewindable rsOpt =
ResultSetFactory.makeRewindable(
new ResultSetStream(vars, ModelFactory.createDefaultModel(), iterOpt));
if (expected != rsOpt.size()) {
System.err.println("Optimized results not as expected");
TextOutput output = new TextOutput((SerializationContext) null);
output.format(System.out, rsOpt);
rsOpt.reset();
}
Assert.assertEquals(expected, rsOpt.size());
iterOpt.close();
Assert.assertTrue(ResultSetCompare.isomorphic(rs, rsOpt));
} finally {
// Restore previous state
if (isEnabled) {
ARQ.set(opt, true);
} else if (isDisabled) {
ARQ.set(opt, false);
} else {
ARQ.unset(opt);
}
}
}
@Override
public QueryIterator execEvaluated(
final Binding binding,
PropFuncArg argSubject,
Node predicate,
PropFuncArg argObject,
ExecutionContext execCxt) {
// check subject is a variable.
if (!argSubject.getArg().isVariable()) throw new QueryExecException("Subject not a variable");
final Var var = Var.alloc(argSubject.getArg());
if (!argObject.getArg().isLiteral()) throw new QueryExecException("Subject not a literal");
String searchTerm = argObject.getArg().getLiteralLexicalForm();
Search search = searchEngine();
Iterator<String> x = search.search(searchTerm);
Iter<String> iter = Iter.iter(x);
QueryIterator qIter =
new QueryIterPlainWrapper(
iter.map(
(item) -> {
return BindingFactory.binding(binding, var, NodeFactory.createURI(item));
}));
return qIter;
}
