wr.return

@wr.return是自定义taglet。主要是针对一些特殊的服务接口，无法通过接口定义了解接口的返回参数说明，需要通过注释来进一步阐释。

/**
 * @wr.param username || String || user's name to login || Y || adams | init add | 0.1 | bob | update | 0.2
 * @wr.param password || String || user's password to login 
 * @wr.param isAdmin || boolean || login as admin || N || adams | init add | 0.1 
 * @wr.return login cookie || http cookie
 */
@RequestMapping(value = "/login", method = RequestMethod.POST)
public String login(HttpServletRequest request) {
    String username = request.getParameter("username").trim();
    return username;
}