*/
@Override
public void propertyChange(PropertyChangeEvent evt) {
if (QueryStatement.STATE_PROPERTY.equals(evt.getPropertyName())) {
if (evt.getSource() instanceof QueryStatement) {
State newState = (State) evt.getNewValue();
switch (newState) {
case INITIAL:
case MATCHING:
addQuery((QueryStatement<?, ?, ?>) evt.getSource());
break;