登录注册页面连接数据库并完成注册(最终章)

1:下面是登录的

package servletDemo;


import com.fasterxml.jackson.databind.ObjectMapper;
import dao.impl.UserDaoImpl;
import domain.ResultInfo;
import domain.User;
import org.apache.commons.beanutils.BeanUtils;
import serviceDemo.impl.userServiceImpl;
import serviceDemo.userService;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
@WebServlet("/caseServlet")
public class caseServlet extends HttpServlet {
    @Override
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //处理乱码
        response.setContentType("text/html;charset=utf-8");
        request.setCharacterEncoding("utf-8");
        //1:接收数据
        //BeanUtils可以自动转换基础数据类型
        User user = new User();
        //封装User对象
        try {
            //Thread.sleep(3000);//休眠时间
            BeanUtils.populate(user,request.getParameterMap());
        } catch (Exception e) {
            e.printStackTrace();
        }
        //2:调用UserDao中的login方法
        UserDaoImpl userDao = new UserDaoImpl();
        User login = userDao.findByUserNamePassword(user.getUsername(), user.getPassword());
        //3:判断user
        ResultInfo info = new ResultInfo();
        if (login != null) {
            //存储数据
            request.getSession().setAttribute("username",login);
            info.setFlag(true);
//            //登录成功
//            //request.getRequestDispatcher("/span.jsp").forward(request,response);
//            response.sendRedirect("/JavaWebNew/header.jsp");
        }else {
            //登录失败
            //注册失败给提示信息添加数据
            info.setFlag(false);
            info.setErrorMsg("登录失败,用户名或者密码不对!!");
//            System.out.println("注册失败");
//            request.setAttribute("msg","登录失败!用户名或者错误!");
        }
        //将info对象序列化为json
        ObjectMapper mapper = new ObjectMapper();
        String json = mapper.writeValueAsString(info);
        //设置content-type
        response.setContentType("application/json;charset=UTF-8");
        //将json数据写回客户端
        response.getWriter().write(json);
    }
}

2:里面的

3:调用方法查询是否有用户名跟密码

4:在servlet层中判断

5:不知道怎么写就复制下来吧

里面如果返回josn对象需要创建两个类

package domain;

import java.io.Serializable;
import java.util.Objects;

/**
 * 用于封装后端返回前端数据对象
 */
public class ResultInfo implements Serializable {
    private boolean flag;//后端返回结果正常为true，发生异常返回false
    private Object data;//后端返回结果数据对象
    private String errorMsg;//发生异常的错误消息

    //无参构造方法
    public ResultInfo() {
    }
    public ResultInfo(boolean flag) {
        this.flag = flag;
    }
    /**
     * 有参构造方法
     * @param flag
     * @param errorMsg
     */
    public ResultInfo(boolean flag, String errorMsg) {
        this.flag = flag;
        this.errorMsg = errorMsg;
    }
    /**
     * 有参构造方法
     * @param flag
     * @param data
     * @param errorMsg
     */
    public ResultInfo(boolean flag, Object data, String errorMsg) {
        this.flag = flag;
        this.data = data;
        this.errorMsg = errorMsg;
    }

    public boolean isFlag() {
        return flag;
    }

    public void setFlag(boolean flag) {
        this.flag = flag;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }

    public String getErrorMsg() {
        return errorMsg;
    }

    public void setErrorMsg(String errorMsg) {
        this.errorMsg = errorMsg;
    }
}

登录注册到这里就结束了,可能有点乱,仔细看一下步骤是能看懂的,有问题可以私信给我,

我会第一时间回答问题的哦!