javaweb

title: javaweb项目-msbms
date: 2020-11-28 11:51:36
tags: javaweb

SMBMS

存在问题

乱码解决

idea运行java项目js中文乱码如何解决

  • VM-OPTION -Dfile.encoding=utf-8
  • Js文件编码改为UTF-BOM

1、简介

数据库架构

如何搭建项目？

  • jar
  • maven

项目搭建

1.利用模板搭建maven-javaweb项目，注意maven配置信息需要重写

2.配置Tomcat

3.测试项目

4.导入jar包`servlet-api，jsp-api，mysql-connector-java，jstl-api，standard

5.创建包结构

6.编写实体类

ORM映射：表-类映射

7.编写基础公共类

  1. 数据库配置文件
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306?useUnicode=true&characterEncoding=utf-8
username=root
password=123456
  1. 编写数据库公共方法
package com.bzf.dao;

import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;

public class BaseDao {
    private static String driver;
    private static String url;
    private static String username;
    private static String password;

    //静态代码块，类加载的时候就初始化
    static{
        Properties properties = new Properties();
        //通过类加载器，读取资源
        InputStream is = BaseDao.class.getClassLoader().getResourceAsStream("db.properties");

        try {
            properties.load(is);
        } catch (IOException e) {
            e.printStackTrace();
        }
        driver = properties.getProperty("driver");
        url = properties.getProperty("url");
        username = properties.getProperty("username");
        password = properties.getProperty("password");
    }
    // 获取数据库连接
    public  static Connection getConnection(){
        Connection connection = null;
        try {
            Class.forName(driver);
            connection = DriverManager.getConnection(url,username,password);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return connection;
    }
    //编写查询公共类
    public static ResultSet  execute(Connection connection,String sql,Object[] params,ResultSet resultSet,PreparedStatement preparedStatement) throws SQLException {
        preparedStatement = connection.prepareStatement(sql);
        for (int i = 0;i<params.length;i++){
            //setObject()，占位符从1开始，但是我们的数组从1开始
            preparedStatement.setObject(i+1,params[i]);
        }
        resultSet = preparedStatement.executeQuery();
        return resultSet;
    }
    //编写 增 删 改 公共方法
    public static int execute (Connection connection,String sql,Object[] params,PreparedStatement preparedStatement) throws SQLException{
        for (int i = 0;i<params.length;i++){
            //setObject()，占位符从1开始，但是我们的数组从1开始
            preparedStatement.setObject(i+1,params[i]);
        }
        int updateRows = preparedStatement.executeUpdate();
        return updateRows;
    }

    //释放资源
    public static Boolean closeResource(Connection connection,PreparedStatement preparedStatement,ResultSet resultSet) throws SQLException {
        Boolean flag = true;

        if (resultSet!=null){
            try {
                resultSet.close();
                //GC回收
                resultSet = null;
            } catch (Exception e) {
                e.printStackTrace();
                flag = false;
            }
        }
        if (preparedStatement!=null){
            try {
                preparedStatement.close();
                //GC回收
                preparedStatement = null;
            } catch (Exception e) {
                e.printStackTrace();
                flag = false;
            }
        }
        if (connection!=null){
            try {
                connection.close();
                //GC回收
                connection = null;
            } catch (Exception e) {
                e.printStackTrace();
                flag = false;
            }
        }
        return flag;
    }
}
  1. 编写字符编码过滤器，注意在web.xml注册

8.导入静态资源，在webapp

3、登陆功能实现

image-20201128095614624

1、编写前端页面

login.jsp，error.jsp

2、设置首页

<!--设置欢迎页面-->
    <welcome-file-list>
        <welcome-file>login.jsp</welcome-file>
    </welcome-file-list>

3、编写Dao层得到用户登陆的接口

public interface UserDao {
    // 得到需要登陆的用户
    public User getLoginUser(Connection connection,String userCode) throws SQLException;
}

4、编写dao接口的实现类

public User getLoginUser(Connection connection, String userCode) throws SQLException {
        PreparedStatement pstm = null;
        ResultSet rs = null;
        User user = null;


        if (connection != null) {
            String sql = "select * from smbms_user where userCode=?";
            Object[] param = {userCode};


            rs = BaseDao.execute(connection, pstm, rs, sql, param);
            if (rs.next()) {
                user = new User();
                user.setId(rs.getInt("id"));
                user.setUserCode(rs.getString("userCode"));
                user.setUserName(rs.getString("userPassword"));
                user.setGender(rs.getInt("gender"));
                user.setBirthday(rs.getDate("birthday"));
                user.setPhone(rs.getString("phone"));
                user.setAddress(rs.getString("address"));
                user.setUserRole(rs.getInt("userRole"));
                user.setCreatedBy(rs.getInt("createdBy"));
                user.setCreationDate(rs.getTimestamp("creationDate"));
                user.setModifyBy(rs.getInt("modifyBy"));
                user.setModifyDate(rs.getTimestamp("modifyDate"));
            }
            BaseDao.closeResource(null, pstm, rs);
        }
    return user;
    }

5、编写业务层接口

public interface UserService {
   //用户登陆
   public User login(String userCode,String password) throws SQLException;
}

6、业务层实现类

public class UserServiceImpl implements UserService {

    //业务层都会调用Dao层，所以我们要引入Dao层
    private UserDao userDao;

    public UserServiceImpl() {
        userDao = new UserDaoImpl();
    }

    public User login(String userCode, String password) throws SQLException {
        Connection connection = null;
        User user = null;

        try {
            connection = BaseDao.getConnection();
            //通过业务层调用Dao层
            user = userDao.getLoginUser(connection, userCode);
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            BaseDao.closeResource(connection, null, null);
        }
        return user;

    }
// 检验代码，发现即使密码错误也可以导出！
    @Test
    public void test() throws SQLException {
        UserServiceImpl userService = new UserServiceImpl();
        User user = userService.login("admin", "12345sfsf67");
        System.out.println(user.getUserPassword());
    }
}

7、编写Servlet

ublic class Loginservlet extends HttpServlet {

    //Servlet：控制层，调用业务层代码

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("进入loginServlet");

        //获取前端用户名和密码
        String userCode = req.getParameter("userCode");
        String userPassword = req.getParameter("userPassword");

        //和数据库中的密码进行对比，调用业务层
        UserServiceImpl userService = new UserServiceImpl();
        try {
            User user = userService.login(userCode, userPassword);//已经把登陆的人从数据库中查询出来了
            if (user!=null){
                // 将用户的信息存放在session中
                req.getSession().setAttribute(Constants.USER_SESSION,user);
                //登陆成功后跳转到frame.jsp页面
                resp.sendRedirect("jsp/frame.jsp");
            } else { //没有查到该用户，无法登陆
                //转发回登陆页面，顺带提示它，用户名或者密码错误
                req.setAttribute("error","用户名或者密码不正确");
                req.getRequestDispatcher("login.jsp").forward(req,resp);
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }



    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

8、注册Servlet

<!--Servlet-->
    <servlet>
        <servlet-name>LoginServlet</servlet-name>
        <servlet-class>com.bzf.servlet.user.Loginservlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LoginServlet</servlet-name>
        <url-pattern>/login.do</url-pattern>
    </servlet-mapping>

登陆功能优化

注销功能

思路：移除Session，返回登陆页面

package com.bzf.servlet.user;

import com.bzf.util.Constants;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class LogoutServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 移除用户的Session
        req.getSession().removeAttribute(Constants.USER_SESSION);
//        req.getSession().setMaxInactiveInterval(0);
        resp.sendRedirect(req.getContextPath()+"/login.jsp");
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

注册页面

    <!--注销登陆-->
    <servlet>
        <servlet-name>LogoutServlet</servlet-name>
        <servlet-class>com.bzf.servlet.user.LogoutServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LogoutServlet</servlet-name>
        <url-pattern>/jsp/logout.do</url-pattern>
    </servlet-mapping>

登陆拦截优化

编写过滤器，针对jsp/*下的文件

    public void doFilter(ServletRequest req, ServletResponse resp, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse  response= (HttpServletResponse) resp;
        User user = (User) request.getSession().getAttribute(Constants.USER_SESSION);

        if (user==null){
            response.sendRedirect(request.getContextPath()+"/error.jsp");
        } else {
            filterChain.doFilter(req,resp);
        }

    }

注册 web.xml

    <!--注销登陆-->    <servlet>        <servlet-name>LogoutServlet</servlet-name>        <servlet-class>com.bzf.servlet.user.LogoutServlet</servlet-class>    </servlet>    <servlet-mapping>        <servlet-name>LogoutServlet</servlet-name>        <url-pattern>/jsp/logout.do</url-pattern>    </servlet-mapping>

密码修改

  1. 导入前端素材

  2. 写项目，建议从底层向上写

image-20201130165324774

3.UserDao接口

    //修改密码    public int updatePwd(Connection connection,int id,int password) throws SQLException;

4.UserDao接口实现类

    public int updatePwd(Connection connection, int id, int password) throws SQLException {        PreparedStatement pstm =null;        int execute = 0;//int execute = Integer.parseInt(null);        if (connection!=null){//企业分工，万一前人，没有传过来connection            String sql = "update smbms_user set `userPassword`= ? where id = ?";            Object[] params = {password,id};            execute = BaseDao.execute(connection, pstm, sql, params);            BaseDao.closeResource(null,pstm,null);        }        return execute;    }

5.userService

    //修改密码    public boolean updatePwd( int id, int password) throws SQLException;

6.UserService实现类

 public boolean updatePwd(int id, int password) throws SQLException {        Connection connection = null;        boolean flag = false;        //修改密码        try {            connection = BaseDao.getConnection();            if (userDao.updatePwd(connection,id,password)>0){                flag = true;            }        } catch (SQLException e) {            e.printStackTrace();        } finally {            BaseDao.closeResource(connection,null,null);            return flag;        }    }

7.UserServlet 复用提取出方法

package com.bzf.servlet.user;import com.bzf.pojo.User;import com.bzf.service.user.UserServiceImpl;import com.bzf.util.Constants;import com.mysql.jdbc.StringUtils;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;import java.sql.SQLException;//实现Servlet复用public class UserServlet extends HttpServlet {    @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);        }    }    @Override    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {        doGet(req, resp);    }    public void updatePwd(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {        //从session里获取id        Object user = req.getSession().getAttribute(Constants.USER_SESSION);        String newpassword = req.getParameter("newpassword");        if (user!=null && newpassword!=null){            UserServiceImpl userService = new UserServiceImpl();            try {                boolean flag = userService.updatePwd(((User) user).getId(), newpassword);                if (flag){                    req.setAttribute("message","修改成功，请退出，使用新密码登陆");                    //密码修改成功，移除当前session                    req.getSession().removeAttribute(Constants.USER_SESSION);//resp.sendRedirect("/login.do");是不可取的                } else {                    req.setAttribute("message","密码修改失败");                }            } catch (SQLException e) {                e.printStackTrace();            }            req.getRequestDispatcher("pwdmodify.jsp").forward(req,resp);        }    }}

8.注册

优化前端密码验证

用户管理实现

思路：

image-20201203154142509

1.导入分页的工具类

2.用户列表页面导入

1、获取用户数量

1、UserDao

 //查询用户总数    public int getUserCount(Connection connection,String username,int userRole) throws SQLException;

2、UserDaoImpl

 public int getUserCount(Connection connection, String userName, int userRole) throws SQLException {        PreparedStatement pstm = null;        ResultSet rs = null;        int count = 0;        if (connection!=null){            StringBuffer sql = new StringBuffer();            sql.append("select count(1) as count from smbms_user u ,smbms_role s where u.userRole=s.id");            ArrayList<Object> list = new ArrayList<Object>();            if (!StringUtils.isNullOrEmpty(userName)){                sql.append(" and u.userName like ?");                list.add("%"+userName+"%");//index:0            }            if (userRole>0){                sql.append(" and u.userRole = ?");//index:1                list.add(userRole);            }            //怎么办list转化为数组            Object[] params = list.toArray();            System.out.println("UserDaoImpl->getUserCount:"+sql.toString());//输出完整的sql语句            rs = BaseDao.execute(connection,pstm,rs,sql.toString(),params);            if(rs.next()){                count = rs.getInt("count");            }            BaseDao.closeResource(null, pstm, rs);        }        return count;    }

3、UserService

    //查询记录数    public int getUserCount(String queryUserName, int queryUserRole) throws SQLException;

4、UserServiceImpl

public int getUserCount(String queryUserName, int queryUserRole) throws SQLException {    // TODO Auto-generated method stub    Connection connection = null;    int count = 0;    System.out.println("queryUserName ---- > " + queryUserName);    System.out.println("queryUserRole ---- > " + queryUserRole);    try {        connection = BaseDao.getConnection();        count = userDao.getUserCount(connection, queryUserName,queryUserRole);    } catch (Exception e) {        // TODO Auto-generated catch block        e.printStackTrace();    }finally{        BaseDao.closeResource(connection, null, null);    }    return count;}

2、获取用户列表

3、获取角色操作

RoleDao

public interface RoleDao {		public List<Role> getRoleList(Connection connection)throws Exception;}

RoleDaoImpl

public class RoleDaoImpl implements RoleDao{	public List<Role> getRoleList(Connection connection) throws Exception {		PreparedStatement pstm = null;		ResultSet rs = null;		List<Role> roleList = new ArrayList<Role>();		if(connection != null){			String sql = "select * from smbms_role";			Object[] params = {};			rs = BaseDao.execute(connection, pstm, rs, sql, params);			while(rs.next()){				Role _role = new Role();				_role.setId(rs.getInt("id"));				_role.setRoleCode(rs.getString("roleCode"));				_role.setRoleName(rs.getString("roleName"));				roleList.add(_role);			}			BaseDao.closeResource(null, pstm, rs);		}				return roleList;	}}

RoleService

public interface RoleService {		public List<Role> getRoleList() throws SQLException;	}

RoleServiceImpl

public class RoleServiceImpl implements RoleService{		private RoleDao roleDao;		public RoleServiceImpl(){		roleDao = new RoleDaoImpl();	}		public List<Role> getRoleList() throws SQLException {		Connection connection = null;		List<Role> roleList = null;		try {			connection = BaseDao.getConnection();			roleList = roleDao.getRoleList(connection);		} catch (Exception e) {			e.printStackTrace();		}finally{			BaseDao.closeResource(connection, null, null);		}		return roleList;	}	}

4、用户显示

  1. 获取用户的前端数据（查询）
  2. 判断请求是否需要执行，看参数的值判断
  3. 为了实现分页，需要计算当前页面和总页面，页面大小
  4. 返回用户列表展示
  5. 返回前端
private void query(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException, SQLException {        //查询用户列表        String queryUserName = request.getParameter("queryname");        String temp = request.getParameter("queryUserRole");        String pageIndex = request.getParameter("pageIndex");        int queryUserRole = 0;        UserService userService = new UserServiceImpl();        List<User> userList = null;        //设置页面容量        int pageSize = Constants.pageSize;        //当前页码        int currentPageNo = 1;        System.out.println("queryUserName servlet--------"+queryUserName);        System.out.println("queryUserRole servlet--------"+queryUserRole);        System.out.println("query pageIndex--------- > " + pageIndex);        if(queryUserName == null){            queryUserName = "";        }        if(temp != null && !temp.equals("")){            queryUserRole = Integer.parseInt(temp);        }        if(pageIndex != null){            try{                currentPageNo = Integer.valueOf(pageIndex);            }catch(NumberFormatException e){                response.sendRedirect("error.jsp");            }        }        //总数量（表）        int totalCount	= userService.getUserCount(queryUserName,queryUserRole);        //总页数        PageSupport pages=new PageSupport();        pages.setCurrentPageNo(currentPageNo);        pages.setPageSize(pageSize);        pages.setTotalCount(totalCount);        int totalPageCount = pages.getTotalPageCount();        //控制首页和尾页        if(currentPageNo < 1){            currentPageNo = 1;        }else if(currentPageNo > totalPageCount){            currentPageNo = totalPageCount;        }        userList = userService.getUserList(queryUserName,queryUserRole,currentPageNo, pageSize);        request.setAttribute("userList", userList);        List<Role> roleList = null;        RoleService roleService = new RoleServiceImpl();        roleList = roleService.getRoleList();        request.setAttribute("roleList", roleList);        request.setAttribute("queryUserName", queryUserName);        request.setAttribute("queryUserRole", queryUserRole);        request.setAttribute("totalPageCount", totalPageCount);        request.setAttribute("totalCount", totalCount);        request.setAttribute("currentPageNo", currentPageNo);        request.getRequestDispatcher("userlist.jsp").forward(request, response);}
【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/aspiration/p/15422771.html