javaweb-34：Ajax验证旧密码实现

优化密码修改，使用ajax

1.阿里巴巴的fastjson

<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>fastjsonartifactId>
    <version>1.2.61version>
dependency>

2.后台代码修改

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
     
    String method = req.getParameter("method");
    if (method.equals("savepwd") && method != null) {
     
        this.updatePwd(req, resp);
    } else if (method.equals("pwdmodify") && method != null) {
     
        this.pwdModify(req, resp);
    }
}

//验证旧密码，Session中有用户的密码
public void pwdModify(HttpServletRequest req, HttpServletResponse resp) {
     
    //从Session里面拿ID
    Object o = req.getSession().getAttribute(Constants.USER_SESSION);
    String oldpassword = req.getParameter("oldpassword");
    //万能的Map：结果集
    Map<String, String> resultMap = new HashMap<String, String>();
    if (o == null) {
     //Session失效了，Session过期了
        resultMap.put("result", "sessionerror");
    } else if (StringUtils.isNullOrEmpty(oldpassword)) {
     //输入的密码为空
        resultMap.put("result", "error");
    } else {
     
        String userPassword = ((User) o).getUserPassword();//Session中用户的密码
        if (oldpassword.equals(userPassword)) {
     
            resultMap.put("result", "true");
        } else {
     
            resultMap.put("result", "false");
        }
    }

    try {
     
        resp.setContentType("application/json");
        PrintWriter writer = resp.getWriter();
        //JSONArray 阿里巴巴的JSON工具类，转换格式
        /*
            resultMap = ["result","sessionerror","result","error"];
            json格式={key:value}
             */
        writer.write(JSONArray.toJSONString(resultMap));
        writer.flush();
        writer.close();
    } catch (IOException e) {
     
        e.printStackTrace();
    }

}

web.xml配置session过期时间

<session-config>
    <session-timeout>30session-timeout>
session-config>