@Override
public Value value(final QueryContext qc) throws QueryException {
final Value val = qc.value(exprs[0]);
if (val.isEmpty()) throw ONEORMORE.get(info);
return val;
}
/**
* Evaluates the specified query.
*
* @param query query
* @return success flag
*/
final boolean query(final String query) {
final Performance p = new Performance();
String error;
if (exception != null) {
error = Util.message(exception);
} else {
try {
long hits = 0;
final boolean run = options.get(MainOptions.RUNQUERY);
final boolean serial = options.get(MainOptions.SERIALIZE);
final int runs = Math.max(1, options.get(MainOptions.RUNS));
for (int r = 0; r < runs; ++r) {
// reuse existing processor instance
if (r != 0) qp = null;
qp(query, context);
parse(p);
if (r == 0) plan(false);
qp.compile();
info.compiling += p.time();
if (r == 0) plan(true);
if (!run) continue;
final PrintOutput po = r == 0 && serial ? out : new NullOutput();
try (final Serializer ser = qp.getSerializer(po)) {
if (maxResults >= 0) {
result = qp.cache(maxResults);
info.evaluating += p.time();
result.serialize(ser);
hits = result.size();
} else {
hits = 0;
final Iter ir = qp.iter();
info.evaluating += p.time();
for (Item it; (it = ir.next()) != null; ) {
ser.serialize(it);
++hits;
checkStop();
}
}
}
qp.close();
info.serializing += p.time();
}
// dump some query info
// out.flush();
// remove string list if global locking is used and if query is updating
if (soptions.get(StaticOptions.GLOBALLOCK) && qp.updating) {
info.readLocked = null;
info.writeLocked = null;
}
return info(info.toString(qp, out.size(), hits, options.get(MainOptions.QUERYINFO)));
} catch (final QueryException | IOException ex) {
exception = ex;
error = Util.message(ex);
} catch (final ProcException ex) {
error = INTERRUPTED;
} catch (final StackOverflowError ex) {
Util.debug(ex);
error = BASX_STACKOVERFLOW.desc;
} catch (final RuntimeException ex) {
extError("");
Util.debug(info());
throw ex;
} finally {
// close processor after exceptions
if (qp != null) qp.close();
}
}
return extError(error);
}