存入xml操作

        //存入数据库
        try {
            //解析xml
            SAXReader reader = new SAXReader();
            String path = this.getServletContext().getRealPath("WEB-INF/classes/users.xml");
            Document dom = reader.read(path);
            Element root = dom.getRootElement();
            //凭空创建userEle保存用户信息
            Element userEle = DocumentHelper.createElement("user");
            userEle.setAttributeValue("username", username);
            userEle.setAttributeValue("password", password);
            userEle.setAttributeValue("nickname", nickname);
            userEle.setAttributeValue("email", email);
            //挂载到根节点
            root.add(userEle);
            //更新xml
            XMLWriter wrtier = new XMLWriter(new FileOutputStream(path),OutputFormat.createPrettyPrint());
            wrtier.write(dom);
            wrtier.close();
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
    }