value not passed to request handler from java snippet

Hi, 

am using below java script to call a request handler and sending "loginToken" value as param, below java script:

var xhr = new XMLHttpRequest();
var url = mx.appUrl + "autologin/";
var params = "loginToken=${loginToken}";
xhr.open("POST",url,true);
xhr.setRequestHeader("Content-Type","application/x-www-form-urlencoded; charset=UTF-8");
xhr.send(params);
location.reload();

Request handler:

private static final String XAS_ID = "XASID";
    protected static ILogNode AUTOLOGINLOGGER = Core.getLogger("AutoLogin");

    class AutoLoginHandler extends RequestHandler {

        @Override
        public void processRequest(IMxRuntimeRequest request, IMxRuntimeResponse response, String arg2)
                throws Exception {
        String valuetoday = arg2;

        AUTOLOGINLOGGER.info("came inside app" + valuetoday);

            if ("POST".equals(request.getHttpServletRequest().getMethod())) {
                try {

            AUTOLOGINLOGGER.info("came inside POST");

                    ISession oldSession = this.getSessionFromRequest(request);
                    String loginToken = request.getParameter("loginToken");
            AUTOLOGINLOGGER.info("login token" +loginToken);

                    if (loginToken != null) {
            AUTOLOGINLOGGER.info("came inside login Token");

}

}

}

}

But this loginToken is coming empty here. Please tell me where the issue is.