code: protected AbstractIndexPage getPageByPos(int pos) {
  		AbstractIndexPage page = subPages[pos];
  		if (page != null) {
  			return page;
  		}
  		page = ind.readPage(subPageIds[pos], this);
  		subPages[pos] = page;
  		return page;
  	}
docs: Returns (and loads, if necessary) the page at the specified position.