code: public String[] getCurrentSelection(final int level) {
          if (level >= this.levelCounter) {
              throw new IllegalArgumentException(
                      "Cannot return current selection: max level is " + this.levelCounter + " (specified: " + level + ")");
          }
          if (this.levels == null) {
              return null;
          }
          return this.levels[level].getCurrentSelection();
      }
docs: <p>
  Returns the matching selectors for a specific selection level, or null if no selector is currently matching
  at that level.
  </p>
  <p>
  This method <strong>should only be called from event handlers</strong> or other code called from these, given
  the information about matching selectors will only be updated before (and after) calling the events
  relevant for that selection.
  </p>
  
  @param level the selection level.
  @return the currently matching selectors for that level.