arcgis token 调用token生成接口，生成报错

    public String getToken() {

        String tokenjson ="";

        String url = portalUrl+"generateToken";

        String param ="";

        StringBuffer buffer = new StringBuffer();

        buffer.append("------footfoodapplicationrequestnetwork\r\n");

        buffer.append("Content-Disposition: form-data; name=\"");

        buffer.append("username");

        buffer.append("\"\r\n\r\n");

        buffer.append(name);

        buffer.append("\r\n");

        buffer.append("------footfoodapplicationrequestnetwork\r\n");

        buffer.append("Content-Disposition: form-data; name=\"");

        buffer.append("password");

        buffer.append("\"\r\n\r\n");

        buffer.append(password);

        buffer.append("\r\n");

        buffer.append("------footfoodapplicationrequestnetwork\r\n");

        buffer.append("Content-Disposition: form-data; name=\"");

        buffer.append("client");

        buffer.append("\"\r\n\r\n");

        buffer.append("requestip");

        buffer.append("\r\n");

        buffer.append("------footfoodapplicationrequestnetwork\r\n");

        buffer.append("Content-Disposition: form-data; name=\"");

        buffer.append("expiration");

        buffer.append("\"\r\n\r\n");

        buffer.append("60");

        buffer.append("\r\n");

        buffer.append("------footfoodapplicationrequestnetwork\r\n");

        buffer.append("Content-Disposition: form-data; name=\"");

        buffer.append("f");

        buffer.append("\"\r\n\r\n");

        buffer.append("json");

        buffer.append("\r\n");

        buffer.append("------footfoodapplicationrequestnetwork--\r\n");

        param=buffer.toString();

        try {

            tokenjson=httpSender.sendPost(url,param);

        } catch (Exception e) {

            e.printStackTrace();

        }

        HashMap hashMap= new HashMap<String,String>();

        String token ="";

        if(tokenjson!=null&&!"".equals(tokenjson)){

            token=tokenjson.substring(10,tokenjson.indexOf("expires")-3);

        }

        return token;

    }