Spring Boot project 第四篇-实训项目day3

原创已于 2022-02-24 11:30:43 修改 · 367 阅读

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于 2022-02-23 21:10:46 首次发布

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本文详细介绍了如何构建一个具备用户登录、注册功能的系统，包括验证规则、异常处理、登录次数限制和冻结机制。涵盖了正则表达式验证、Spring Boot集成、数据库操作及JWT认证等关键环节。

1.搭建环境：JDK1.8+IDEA2017+MySQL8.0

2.功能要求：

登录功能：

1. 用户名为6-20位字符串，支持字母、数字；

2. 密码为8-20位字符串，支持字母、数字、特殊字符；

3. 登录失败有原因提示；

4. 5分钟内5次登录失败冻结账号10分钟；

注册功能：

1. 注册信息包括用户名、密码、手机号、出生年月、性别；

2. 用户名、手机号不可重复；

3. 用户名为6-20位字符串，支持字母、数字；

4. 密码为8-20位字符串，支持字母、数字、特殊字符；

5. 验证手机号格式；

6. 注册失败有原因提示；

3.登录实现

3.1编写UserService类

package com.example.shop.service;

import com.example.shop.model.User;

public interface UserService {

    Integer checkLoginLog(User user);

    User login(User user, String ip);

    Integer reg(User user);
}

3.2编写实现类

package com.example.shop.service.impl;

import com.example.shop.dao.LoginLogDAO;
import com.example.shop.dao.LoginLogSpecDAO;
import com.example.shop.dao.UserDAO;
import com.example.shop.model.LoginLog;
import com.example.shop.model.LoginLogExample;
import com.example.shop.model.User;
import com.example.shop.model.UserExample;
import com.example.shop.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;
import org.springframework.util.DigestUtils;

import java.util.Date;
import java.util.List;


@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserDAO userDAO;

   /* @Autowired
    private LoginLogDAO loginLogDAO;

    @Autowired
    private LoginLogSpecDAO loginLogSpecDAO;*/

    /**
     * 检查登录失败次数
     */
 /*   @Override
    public Integer checkLoginLog(User user){
        //判断该账号是否可以登录
        LoginLog loginLog = new LoginLog();
        loginLog.setUsername(user.getUsername());
        return loginLogSpecDAO.countByUsername(loginLog);
    }*/


    /**
     * 登录验证用户名和密码
     * @param user
     * @return
     */
    @Override
    public User login(User user, String ip) {
        //判断用户名密码是否存在
        UserExample userExample = new UserExample();
        userExample.createCriteria().andUsernameEqualTo(user.getUsername()).andPasswordEqualTo(DigestUtils.md5DigestAsHex(user.getPassword().getBytes()));
        List<User> users = userDAO.selectByExample(userExample);

      /*  //增加登录日志
        int flag = !CollectionUtils.isEmpty(users) ? 1 : 0;
        LoginLog loginLog = new LoginLog();
        loginLog.setUsername(user.getUsername());
        loginLog.setIp(ip);
        loginLog.setLoginTime(new Date());
        loginLog.setLoginSuccess(flag);
        loginLogDAO.insertSelective(loginLog);*/

        return !CollectionUtils.isEmpty(users) ? users.get(0) : null;
    }

    /**
     * 新用户注册
     * @param user
     * @return
     */
    @Override
    public Integer reg(User user){
        //判断手机号和用户名是否重复
        UserExample ue = new UserExample();
        ue.createCriteria().andUsernameEqualTo(user.getUsername());
        ue.or().andPhoneEqualTo(user.getPhone());
        List<User> users = userDAO.selectByExample(ue);
        if(!CollectionUtils.isEmpty(users)){
            return -1;
        }

        //密码加密，增加创建时间，注册用户信息
        user.setPassword(DigestUtils.md5DigestAsHex(user.getPassword().getBytes()));
        user.setCreatedTime(new Date());
        int rs = userDAO.insertSelective(user);

        //如果添加成功，获取刚插入的id
        if(rs > 0){
            return user.getId();
        }
        return rs;
    }
}

3.3校验功能有两种方式：第一种使用正则表达式

package com.example.shop_test.controller;


import com.example.shop_test.common.util.JwtUtils;
import com.example.shop_test.common.util.ResultModel;
import com.example.shop_test.model.User;
import com.example.shop_test.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;

import java.util.HashMap;
import java.util.Map;

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    UserService userService;

    /**
     * 用户登录
     * @param user
     * @return
     */
    @PostMapping("/login")
    @ResponseBody
    public ResultModel login(@RequestBody User user){
        //验证参数，也可以使用validated
        if(null == user.getUsername()){
            return ResultModel.error("请输入用户名");
        }
        String userExp = "^[A-Za-z0-9]{6,20}$";
        if(!user.getUsername().matches(userExp)) {
            return ResultModel.error("用户名为6-20位字母、数字");
        }
        if(null == user.getPassword()){
            return ResultModel.error("请输入密码");
        }
        String pwdExp = "^[A-Za-z0-9_!@#$%&*]{8,20}$";
        if(!user.getPassword().matches(pwdExp)) {
            return ResultModel.error("密码为8-20位字母、数字、特殊字符");
        }

        //调用登录方法
        User rs = userService.login(user);
        if(null == rs){
            return ResultModel.error("用户名密码错误");
        }

        //jwt 封装token返回给前端 后续接口用token验证身份
        String token = JwtUtils.createToken(rs.getId(), rs.getUsername());
        Map resultMap = new HashMap();
        resultMap.put("id", rs.getId());
        resultMap.put("token", token);
        return ResultModel.success(resultMap);

    }

    /**
     * 用户注册
     * @param user
     * @return
     */
    @PostMapping("reg")
    @ResponseBody
    public ResultModel reg(@RequestBody User user){

        Integer rs = userService.reg(user);

        if(0 == rs){
            return ResultModel.error("注册失败");
        }

        //jwt 封装token返回给前端 后续接口用token验证身份
        String token = JwtUtils.createToken(rs, user.getUsername());
        Map resultMap = new HashMap();
        resultMap.put("id", rs);
        resultMap.put("token", token);
        return ResultModel.success(resultMap);
    }
}

第二种使用注解@Validated：

步骤如下：

（1）先创建两个接口Reg和Login

package com.example.shop.common.validation.user;

/**
 * 注册校验
 */
public interface Login {
}

package com.example.shop.common.validation.user;

/**
 * 注册校验
 */
public interface Reg {
}

（2）使用这两个接口绑定@Validated注解上（@Validated(Reg.class)）

（3）在model模型中绑定属性值

package com.example.shop.model;

import com.example.shop.common.validation.user.Login;
import com.example.shop.common.validation.user.Reg;

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.Pattern;
import java.util.Date;

public class User {
    private Integer id;

    @NotBlank(message = "用户名不能为空",groups = {Reg.class, Login.class})
    @Pattern(regexp = "^[A-Za-z0-9]{6,20}$", message = "用户名格式错误", groups = {Reg.class, Login.class})
    private String username;

    @NotBlank(message = "密码不能为空",groups = {Reg.class, Login.class})
    @Pattern(regexp = "^[A-Za-z0-9_!@#$%&*]{8,20}$", message = "密码格式错误", groups = {Reg.class, Login.class})
    private String password;

    private String nickname;

    private Date birthday;

    private Integer sex;
    
    private String phone;

    private String idcardNum;

    private Integer status;

    private Date createdTime;

    private Date modifiedTime;

    private Integer isDelete;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getNickname() {
        return nickname;
    }

    public void setNickname(String nickname) {
        this.nickname = nickname;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public Integer getSex() {
        return sex;
    }

    public void setSex(Integer sex) {
        this.sex = sex;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public String getIdcardNum() {
        return idcardNum;
    }

    public void setIdcardNum(String idcardNum) {
        this.idcardNum = idcardNum;
    }

    public Integer getStatus() {
        return status;
    }

    public void setStatus(Integer status) {
        this.status = status;
    }

    public Date getCreatedTime() {
        return createdTime;
    }

    public void setCreatedTime(Date createdTime) {
        this.createdTime = createdTime;
    }

    public Date getModifiedTime() {
        return modifiedTime;
    }

    public void setModifiedTime(Date modifiedTime) {
        this.modifiedTime = modifiedTime;
    }

    public Integer getIsDelete() {
        return isDelete;
    }

    public void setIsDelete(Integer isDelete) {
        this.isDelete = isDelete;
    }
}

（4）导入ValidationExceptionHandler类（监听格式是否出错）

package com.example.shop.config;


import com.example.shop.common.util.ResultModel;
import com.example.shop.exception.LoginException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.context.support.DefaultMessageSourceResolvable;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import javax.validation.ConstraintViolation;
import javax.validation.ConstraintViolationException;
import java.util.List;
import java.util.stream.Collectors;

/**
 * validation
 */
@Slf4j
@RestControllerAdvice(basePackages = {"com.example"})
public class ValidationExceptionHandler {
    public ValidationExceptionHandler() {
    }

    @ExceptionHandler({MethodArgumentNotValidException.class})
    public ResultModel<?> validationErrorHandler(MethodArgumentNotValidException e) {
        List<String> errorInfo = e
                .getBindingResult()
                .getAllErrors()
                .stream()
                .map(DefaultMessageSourceResolvable::getDefaultMessage)
                .collect(Collectors.toList());
        log.error(errorInfo.toString());
        return new ResultModel(401, errorInfo.toString());
    }

    @ExceptionHandler({ConstraintViolationException.class})
    public ResultModel validationParamErrorHandler(ConstraintViolationException e) {
        List<String> errorInfo = e
                .getConstraintViolations()
                .stream()
                .map(ConstraintViolation::getMessage)
                .collect(Collectors.toList());
        log.error(errorInfo.toString());
        return new ResultModel(402, errorInfo.toString());
    }

}

3.4编写controller类

package com.example.shop.controller;

import com.example.shop.common.util.IpUtils;
import com.example.shop.common.util.JwtUtils;
import com.example.shop.common.validation.user.Login;
import com.example.shop.common.validation.user.Reg;
import com.example.shop.model.User;
import com.example.shop.service.UserService;
import com.example.shop.common.util.ResultModel;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;

import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    UserService userService;

    /**
     * 用户登录
     * @param user
     * @return
     */
    @PostMapping("/login")
    @ResponseBody
    public ResultModel login(@Validated(Login.class) @RequestBody User user, HttpServletRequest request){
      /*  //验证是否可以登录
        Integer count = userService.checkLoginLog(user);
        if(count > 4){
            return ResultModel.error("用户禁止登录");
        }*/

        //调用登录方法
        String ip = IpUtils.getIpAddr(request);
        User rs = userService.login(user, ip);
        if(null == rs){
            return ResultModel.error("用户名密码错误");
        }

        //jwt 封装token返回给前端 后续接口用token验证身份
        String token = JwtUtils.createToken(rs.getId(), rs.getUsername());
        Map resultMap = new HashMap();
        resultMap.put("id", rs.getId());
        resultMap.put("token", token);
        return ResultModel.success(resultMap);

    }

    /**
     * 用户注册
     * @param user
     * @return
     */
    @PostMapping("reg")
    @ResponseBody
    public ResultModel reg(@Validated(Reg.class) @RequestBody User user){

        Integer rs = userService.reg(user);

        if(0 == rs){
            return ResultModel.error("注册失败");
        }else if(-1 == rs){
            return ResultModel.error("用户名或手机已存在");
        }

        //jwt 封装token返回给前端 后续接口用token验证身份
        String token = JwtUtils.createToken(rs, user.getUsername());
        Map resultMap = new HashMap();
        resultMap.put("id", rs);
        resultMap.put("token", token);
        return ResultModel.success(resultMap);
    }
}

3.5拦截器的实现

（1）编写拦截器LoginInterceptor

package com.example.shop.common.interceptor;

import com.example.shop.common.util.JwtUtils;
import com.example.shop.exception.LoginException;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Slf4j
@Configuration
public class LoginInterceptor implements HandlerInterceptor {

    /**
     * 验证登录状态
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String token = request.getHeader("token");
        if (StringUtils.isBlank(token)) {
            log.error("token为空或token已过期");
            throw new LoginException(400,"token为空或token已过期");
        }
        if (!JwtUtils.verify(token)) {
            log.error("token不正确");
            throw new LoginException(400, "token不正确");
        }
        String id = JwtUtils.getClaimByName(token, "id");
        String username = JwtUtils.getClaimByName(token, "username");
        request.getSession().setAttribute("id", id);
        request.getSession().setAttribute("username", username);
        return true;
    }
}

（2）定义自己的配置类 MyMvcConfig，加入拦截器

package com.example.shop.config;

import com.example.shop.common.interceptor.LoginInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
 * 列举不需要验证登录状态的接口
 */
@Configuration
public class MyMvcConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new LoginInterceptor()).addPathPatterns("/**")
                .excludePathPatterns("/user/login")
                .excludePathPatterns("/user/reg");
    }
}

（3）定义一个异常类LoginException

package com.example.shop.exception;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;


@Data
@AllArgsConstructor
@NoArgsConstructor
public class LoginException extends RuntimeException{
    private int code;
    private String message;

    public LoginException(String message) {
        super(message);
    }

    public LoginException(String message, Throwable cause) {
        super(message, cause);
    }
}

3.6冻结登录实现

（1）自定义一个DAO类，LoginLogSpecDAO

package com.example.shop.dao;

import com.example.shop.model.LoginLog;
import org.apache.ibatis.annotations.Param;

import java.util.List;

public interface LoginLogSpecDAO {
    int countByUsername(LoginLog loginLog);

}

（2）model类LoginLog自动生成Mybatis

package com.example.shop.model;

import java.util.Date;

public class LoginLog {
    private Integer id;

    private String username;

    private String ip;

    private Integer loginSuccess;

    private Date loginTime;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getIp() {
        return ip;
    }

    public void setIp(String ip) {
        this.ip = ip;
    }

    public Integer getLoginSuccess() {
        return loginSuccess;
    }

    public void setLoginSuccess(Integer loginSuccess) {
        this.loginSuccess = loginSuccess;
    }

    public Date getLoginTime() {
        return loginTime;
    }

    public void setLoginTime(Date loginTime) {
        this.loginTime = loginTime;
    }
}

<table tableName="login_log" domainObjectName="LoginLog" mapperName="LoginLogDAO" catalog="shop">
            <property name="ignoreQualifiersAtRuntime" value="true"/>
            <generatedKey column="id" sqlStatement="MySql" identity="true"/>
        </table>

（3）编写LoginLogSpecDAO.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.shop.dao.LoginLogSpecDAO">
    <!-- 根据用户id查询角色名称 -->
    <select id="countByUsername" parameterType="com.example.shop.model.LoginLog" resultType="java.lang.Integer">
        select count(id)
        from login_log
        where username = #{username}
        and login_time > DATE_SUB(NOW(),INTERVAL 5 MINUTE)
        and login_success = 0
    </select>

</mapper>

（4）重写实现类

package com.example.shop.service.impl;

import com.example.shop.dao.LoginLogDAO;
import com.example.shop.dao.LoginLogSpecDAO;
import com.example.shop.dao.UserDAO;
import com.example.shop.model.LoginLog;
import com.example.shop.model.LoginLogExample;
import com.example.shop.model.User;
import com.example.shop.model.UserExample;
import com.example.shop.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;
import org.springframework.util.DigestUtils;

import java.util.Date;
import java.util.List;


@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserDAO userDAO;

    @Autowired
    private LoginLogDAO loginLogDAO;

    @Autowired
    private LoginLogSpecDAO loginLogSpecDAO;

    /**
     * 检查登录失败次数
     */
    @Override
    public Integer checkLoginLog(User user){
        //判断该账号是否可以登录
        LoginLog loginLog = new LoginLog();
        loginLog.setUsername(user.getUsername());
        return loginLogSpecDAO.countByUsername(loginLog);
    }


    /**
     * 登录验证用户名和密码
     * @param user
     * @return
     */
    @Override
    public User login(User user, String ip) {
        //判断用户名密码是否存在
        UserExample userExample = new UserExample();
        userExample.createCriteria().andUsernameEqualTo(user.getUsername()).andPasswordEqualTo(DigestUtils.md5DigestAsHex(user.getPassword().getBytes()));
        List<User> users = userDAO.selectByExample(userExample);

        //增加登录日志
        int flag = !CollectionUtils.isEmpty(users) ? 1 : 0;
        LoginLog loginLog = new LoginLog();
        loginLog.setUsername(user.getUsername());
        loginLog.setIp(ip);
        loginLog.setLoginTime(new Date());
        loginLog.setLoginSuccess(flag);
        loginLogDAO.insertSelective(loginLog);

        return !CollectionUtils.isEmpty(users) ? users.get(0) : null;
    }

    /**
     * 新用户注册
     * @param user
     * @return
     */
    @Override
    public Integer reg(User user){
        //判断手机号和用户名是否重复
        UserExample ue = new UserExample();
        ue.createCriteria().andUsernameEqualTo(user.getUsername());
        ue.or().andPhoneEqualTo(user.getPhone());
        List<User> users = userDAO.selectByExample(ue);
        if(!CollectionUtils.isEmpty(users)){
            return -1;
        }

        //密码加密，增加创建时间，注册用户信息
        user.setPassword(DigestUtils.md5DigestAsHex(user.getPassword().getBytes()));
        user.setCreatedTime(new Date());
        int rs = userDAO.insertSelective(user);

        //如果添加成功，获取刚插入的id
        if(rs > 0){
            return user.getId();
        }
        return rs;
    }
}

3.7postman测试

3.8工具类

IpUtils

package com.example.shop.common.util;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

public class IpUtils {
    public static String getIpAddr(HttpServletRequest request) {
        String ipAddress = null;
        try {
            ipAddress = request.getHeader("x-forwarded-for");
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("WL-Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getRemoteAddr();
                if (ipAddress.equals("127.0.0.1")) {
                    // 根据网卡取本机配置的IP
                    InetAddress inet = null;
                    try {
                        inet = InetAddress.getLocalHost();
                    } catch (UnknownHostException e) {
                        e.printStackTrace();
                    }
                    ipAddress = inet.getHostAddress();
                }
            }
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            if (ipAddress != null && ipAddress.length() > 15) { // "***.***.***.***".length()
                // = 15
                if (ipAddress.indexOf(",") > 0) {
                    ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
                }
            }
        } catch (Exception e) {
            ipAddress="";
        }
        // ipAddress = this.getRequest().getRemoteAddr();

        return ipAddress;
    }
}

JwtUtils

package com.example.shop.common.util;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.interfaces.DecodedJWT;

import java.util.Date;

/**
 * @author dhl
 * @datetime 2021/8/17  13:47
 */
public class JwtUtils {
    /**
     * 超时时间
     */
    private static final long TIME_OUT_MS = 1000 * 60 * 60 * 24;
    /**
     * 加密方式
     */
    private static final String ENCRYPT ="wqw123";
    /**
     * 算法
     */
    private static final Algorithm ALGORITHM = Algorithm.HMAC256(ENCRYPT);

    /**
     * 生成签名，30min后过期
     * @param id
     * @return
     */
    public static String createToken(Integer id, String username){
        Date date = new Date(System.currentTimeMillis() + TIME_OUT_MS);
        return JWT.create()
                // 设置荷载 payload
                .withClaim("id", id)
                .withClaim("username", username)
                // 设置过期时间
                .withExpiresAt(date)
                .sign(ALGORITHM);
    }

    /**
     * 验证token是否正确
     * @param token
     * @return
     */
    public static boolean verify(String token) {
        try {
            JWTVerifier verifier = JWT.require(ALGORITHM).build();
            verifier.verify(token);
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }

    /**
     * 获取token中的信息
     * @param token
     * @param name
     * @return
     */
    public static String getClaimByName(String token, String name) {
        DecodedJWT jwt = JWT.decode(token);
        return jwt.getClaim(name).asString();
    }
}

ResultModel

package com.example.shop.common.util;

import lombok.Data;

@Data
public class ResultModel<T> {
    private int code;
    private String message="";
    private T content;
    public ResultModel(){
    }
    public ResultModel(int code,String message){
        this.code = code;
        this.message = message;
    }
    public ResultModel(int code,String message,T content){
        this.code = code;
        this.message = message;
        this.content = content;
    }
    public static <T> ResultModel<T> success(String message,T content){
        return new ResultModel<T>(0,message,content);
    }
    public static <T> ResultModel<T> success(T content){
        return new ResultModel<T>(0,"success",content);
    }
    public static <T> ResultModel<T> error(int code,String message){
        return new ResultModel<T>(code,message);
    }
    public static <T> ResultModel<T> error(String message){
        return new ResultModel<T>(-1,message);
    }
    public static <T> ResultModel<T> error(){
        return new ResultModel<T>(-1,"error");
    }
}