求助servlet 这段代码什么意思

     */
    @RequestMapping("/getTile.do")
    public @ResponseBody String getTile(HttpServletResponse response,
            @RequestParam(value = "map_id", required = true) String mapId,
            @RequestParam(required = true) int level,
            @RequestParam(value = "tile_x", required = true) int x,
            @RequestParam(value = "tile_y", required = true) int y,
            @RequestParam(value = "tile_data_kind", required = true) int tileDataKind) {

        // JSONとしてリターン
        response.setContentType(GooMapConstant.CONTENT_TYPE_BINARY);

        // TODO

        StringBuffer rtn = new StringBuffer();

        rtn.append("mtllib GEOSPACE_16_13.MTL" + GooMapConstant.ENTER);
        rtn.append(GooMapConstant.ENTER);
        rtn.append("g GEOSPACE_16_13_120" + GooMapConstant.ENTER);
        rtn.append(GooMapConstant.ENTER);
        rtn.append("usemtl GEOSPACE_16_13_120" + GooMapConstant.ENTER);
        rtn.append(GooMapConstant.ENTER);
        rtn.append("v 502944180.0 128390668.0 30.0" + GooMapConstant.ENTER);
        rtn.append("v 502944275.0 128390593.0 30.0" + GooMapConstant.ENTER);
        rtn.append("v 502944239.0 128390563.0 30.0" + GooMapConstant.ENTER);
        rtn.append("v 502944332.0 128390489.0 30.0" + GooMapConstant.ENTER);

        return rtn.toString();

谁知道这段代码什么意思？

这不是servlet吧，，是springmvc，，小括号内就是接收请求的参数，，然后返回一个json字符串回去