public function getMapHeadings()
    {
        if (!$this->headings && !$this->mappablecols) {
            return;
        }
        $out = new Arraylist();
        foreach ($this->headings as $heading) {
            $dropdown = $this->createHeadingDropdown($heading);
            if (is_array($this->mappingvalues) &&
                isset($this->mappingvalues[$heading])
            ) {
                $dropdown->setValue($this->mappingvalues[$heading]);
            }
            $out->push(new ArrayData(array(
                "Heading" => $heading,
                "Dropdown" => $dropdown
            )));
        }

        return $out;
    }