SMBMS

SMBMS是超市订单管理系统的简称

数据库：

项目如何让搭建？

考虑使用不使用Maven？ 依赖，jar

项目搭建准备工作

1.搭建一个mavenweb项目

2.配置Tomcat

3.测试项目是否能够跑起来

4.导入项目中会遇到的jar包

jsp,servlet,mysql驱动，jstl，stand...

  <dependencies>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>servlet-api</artifactId>
      <version>2.5</version>
    </dependency>
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.2</version>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.47</version>
    </dependency>
    <!--JSTL表达式的依赖-->
    <dependency>
      <groupId>javax.servlet.jsp.jstl</groupId>
      <artifactId>jstl-api</artifactId>
      <version>1.2</version>
    </dependency>
    <!--standard标签库-->
    <dependency>
      <groupId>taglibs</groupId>
      <artifactId>standard</artifactId>
      <version>1.1.2</version>
    </dependency>
  </dependencies>

5.创建项目包结构

6.编写实体类

package com.jibu.pojo;

import java.util.Date;

public class User {
    private Integer id; //id
    private String userCode; //用户编码
    private String userName; //用户名称
    private String userPassword; //用户密码
    private Integer gender;  //性别
    private Date birthday;  //出生日期
    private String phone;   //电话
    private String address; //地址
    private Integer userRole;    //用户角色
    private Integer createdBy;   //创建者
    private Date creationDate; //创建时间
    private Integer modifyBy;     //更新者
    private Date modifyDate;   //更新时间

    private Integer age;//年龄
    private String userRoleName;    //用户角色名称


    public String getUserRoleName() {
        return userRoleName;
    }
    public void setUserRoleName(String userRoleName) {
        this.userRoleName = userRoleName;
    }
    public Integer getAge() {
		/*long time = System.currentTimeMillis()-birthday.getTime();
		Integer age = Long.valueOf(time/365/24/60/60/1000).IntegerValue();*/
        Date date = new Date();
        Integer age = date.getYear()-birthday.getYear();
        return age;
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUserCode() {
        return userCode;
    }
    public void setUserCode(String userCode) {
        this.userCode = userCode;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public String getUserPassword() {
        return userPassword;
    }
    public void setUserPassword(String userPassword) {
        this.userPassword = userPassword;
    }
    public Integer getGender() {
        return gender;
    }
    public void setGender(Integer gender) {
        this.gender = gender;
    }
    public Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
    public Integer getUserRole() {
        return userRole;
    }
    public void setUserRole(Integer userRole) {
        this.userRole = userRole;
    }
    public Integer getCreatedBy() {
        return createdBy;
    }
    public void setCreatedBy(Integer createdBy) {
        this.createdBy = createdBy;
    }
    public Date getCreationDate() {
        return creationDate;
    }
    public void setCreationDate(Date creationDate) {
        this.creationDate = creationDate;
    }
    public Integer getModifyBy() {
        return modifyBy;
    }
    public void setModifyBy(Integer modifyBy) {
        this.modifyBy = modifyBy;
    }
    public Date getModifyDate() {
        return modifyDate;
    }
    public void setModifyDate(Date modifyDate) {
        this.modifyDate = modifyDate;
    }

}

package com.jibu.pojo;

import java.util.Date;

public class Role {

    private Integer id;   //id
    private String roleCode; //角色编码
    private String roleName; //角色名称
    private Integer createdBy; //创建者
    private Date creationDate; //创建时间
    private Integer modifyBy; //更新者
    private Date modifyDate;//更新时间

    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getRoleCode() {
        return roleCode;
    }
    public void setRoleCode(String roleCode) {
        this.roleCode = roleCode;
    }
    public String getRoleName() {
        return roleName;
    }
    public void setRoleName(String roleName) {
        this.roleName = roleName;
    }
    public Integer getCreatedBy() {
        return createdBy;
    }
    public void setCreatedBy(Integer createdBy) {
        this.createdBy = createdBy;
    }
    public Date getCreationDate() {
        return creationDate;
    }
    public void setCreationDate(Date creationDate) {
        this.creationDate = creationDate;
    }
    public Integer getModifyBy() {
        return modifyBy;
    }
    public void setModifyBy(Integer modifyBy) {
        this.modifyBy = modifyBy;
    }
    public Date getModifyDate() {
        return modifyDate;
    }
    public void setModifyDate(Date modifyDate) {
        this.modifyDate = modifyDate;
    }

}

package com.jibu.pojo;

import java.util.Date;

public class Provider {

    private Integer id;   //id
    private String proCode; //供应商编码
    private String proName; //供应商名称
    private String proDesc; //供应商描述
    private String proContact; //供应商联系人
    private String proPhone; //供应商电话
    private String proAddress; //供应商地址
    private String proFax; //供应商传真
    private Integer createdBy; //创建者
    private Date creationDate; //创建时间
    private Integer modifyBy; //更新者
    private Date modifyDate;//更新时间
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getProCode() {
        return proCode;
    }
    public void setProCode(String proCode) {
        this.proCode = proCode;
    }
    public String getProName() {
        return proName;
    }
    public void setProName(String proName) {
        this.proName = proName;
    }
    public String getProDesc() {
        return proDesc;
    }
    public void setProDesc(String proDesc) {
        this.proDesc = proDesc;
    }
    public String getProContact() {
        return proContact;
    }
    public void setProContact(String proContact) {
        this.proContact = proContact;
    }
    public String getProPhone() {
        return proPhone;
    }
    public void setProPhone(String proPhone) {
        this.proPhone = proPhone;
    }
    public String getProAddress() {
        return proAddress;
    }
    public void setProAddress(String proAddress) {
        this.proAddress = proAddress;
    }
    public String getProFax() {
        return proFax;
    }
    public void setProFax(String proFax) {
        this.proFax = proFax;
    }
    public Integer getCreatedBy() {
        return createdBy;
    }
    public void setCreatedBy(Integer createdBy) {
        this.createdBy = createdBy;
    }
    public Date getCreationDate() {
        return creationDate;
    }
    public void setCreationDate(Date creationDate) {
        this.creationDate = creationDate;
    }
    public Integer getModifyBy() {
        return modifyBy;
    }
    public void setModifyBy(Integer modifyBy) {
        this.modifyBy = modifyBy;
    }
    public Date getModifyDate() {
        return modifyDate;
    }
    public void setModifyDate(Date modifyDate) {
        this.modifyDate = modifyDate;
    }


}

package com.jibu.pojo;

import java.math.BigDecimal;
import java.util.Date;

public class Bill {
    private Integer id;   //id
    private String billCode; //账单编码
    private String productName; //商品名称
    private String productDesc; //商品描述
    private String productUnit; //商品单位
    private BigDecimal productCount; //商品数量
    private BigDecimal totalPrice; //总金额
    private Integer isPayment; //是否支付
    private Integer providerId; //供应商ID
    private Integer createdBy; //创建者
    private Date creationDate; //创建时间
    private Integer modifyBy; //更新者
    private Date modifyDate;//更新时间

    private String providerName;//供应商名称


    public String getProviderName() {
        return providerName;
    }
    public void setProviderName(String providerName) {
        this.providerName = providerName;
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getBillCode() {
        return billCode;
    }
    public void setBillCode(String billCode) {
        this.billCode = billCode;
    }
    public String getProductName() {
        return productName;
    }
    public void setProductName(String productName) {
        this.productName = productName;
    }
    public String getProductDesc() {
        return productDesc;
    }
    public void setProductDesc(String productDesc) {
        this.productDesc = productDesc;
    }
    public String getProductUnit() {
        return productUnit;
    }
    public void setProductUnit(String productUnit) {
        this.productUnit = productUnit;
    }
    public BigDecimal getProductCount() {
        return productCount;
    }
    public void setProductCount(BigDecimal productCount) {
        this.productCount = productCount;
    }
    public BigDecimal getTotalPrice() {
        return totalPrice;
    }
    public void setTotalPrice(BigDecimal totalPrice) {
        this.totalPrice = totalPrice;
    }
    public Integer getIsPayment() {
        return isPayment;
    }
    public void setIsPayment(Integer isPayment) {
        this.isPayment = isPayment;
    }

    public Integer getProviderId() {
        return providerId;
    }
    public void setProviderId(Integer providerId) {
        this.providerId = providerId;
    }
    public Integer getCreatedBy() {
        return createdBy;
    }
    public void setCreatedBy(Integer createdBy) {
        this.createdBy = createdBy;
    }
    public Date getCreationDate() {
        return creationDate;
    }
    public void setCreationDate(Date creationDate) {
        this.creationDate = creationDate;
    }
    public Integer getModifyBy() {
        return modifyBy;
    }
    public void setModifyBy(Integer modifyBy) {
        this.modifyBy = modifyBy;
    }
    public Date getModifyDate() {
        return modifyDate;
    }
    public void setModifyDate(Date modifyDate) {
        this.modifyDate = modifyDate;
    }


}

 ORM映射：表和类映射

7.编写基础公共类

        1.数据库配置文件
        db.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/jdbc?useUnicode=true&characterEncoding=utf-8&useSSL=false
username=root
password=123456

        2.编写数据库的公共类

package com.jibu.dao;

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

//操作数据库的公共类
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了
    static {
        Properties properties = new Properties();
        //通过类加载器读取对应的资源
        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");
    }

    //获取数据库的连接
    public static Connection getConnection(){
        Connection connection = null;
        try {
            Class.forName(driver);
            connection = DriverManager.getConnection(url, username, password);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return connection;
    }

    //编写查询公共方法
    public static ResultSet execute(Connection connection,String sql,Object[] params,ResultSet resultSet,PreparedStatement preparedStatement) throws SQLException {
        //预编译的SQL, 在后面直接执行就可以了
        preparedStatement = connection.prepareStatement(sql);

        for (int i = 0; i < params.length; i++) {
            //setObject,占位符从1开始，但是我们的数组是从0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 {
        preparedStatement = connection.prepareStatement(sql);

        for (int i = 1; i < params.length; i++) {
            //setObject,占位符从1开始，但是我们的数组是从0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){
        boolean flag = true;
        if (resultSet != null) {
            try {
                resultSet.close();
                //GC回收
                resultSet = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        if (preparedStatement != null) {
            try {
                preparedStatement.close();
                //GC回收
                preparedStatement = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        if (connection != null) {
            try {
                connection.close();
                //GC回收
                connection = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        return flag;
    }
}

         3.编写字符编码过滤器

package com.jibu.filter;

import javax.servlet.*;
import java.io.IOException;

public class CharacterEncodingFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");

        chain.doFilter(request,response);
    }

    @Override
    public void destroy() {

    }
}

    <!--字符编码过滤器-->
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>com.jibu.filter.CharacterEncodingFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>CharacterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

8.导入静态资源 

地址：smbms: 狂神说Java Javaweb练习项目 超市订单管理系统 SMBMS smbmsTomcat10.1.5+jdk21+Mariadb

登录功能实现

流程结构

1.编写前端页面 

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层登录用户登录的接口

package com.jibu.dao.user;

import com.jibu.pojo.User;

import java.sql.Connection;
import java.sql.SQLException;

public interface UserDao {

    //得到要登陆的用户
    public User getLoginUser(Connection connection,String userCode) throws SQLException;

}

4. 编写接口的实现类

package com.jibu.dao.user;

import com.jibu.dao.BaseDao;
import com.jibu.pojo.User;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class UserDaoImpl implements UserDao{
    @Override
    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[] params = {userCode};


                rs = BaseDao.execute(connection, pstm, rs, sql, params);

                if (rs.next()){
                    user = new User();
                    user.setId(rs.getInt("id"));
                    user.setUserCode(rs.getString("userCode"));
                    user.setUserName(rs.getString("userName"));
                    user.setUserPassword(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.业务层接口

package com.jibu.service.user;

import com.jibu.pojo.User;

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

6.业务层实现类 

package com.jibu.service.user;

import com.jibu.dao.BaseDao;
import com.jibu.dao.user.UserDao;
import com.jibu.dao.user.UserDaoImpl;
import com.jibu.pojo.User;
import org.junit.Test;

import java.sql.Connection;
import java.sql.SQLException;

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();
    }

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

        try {
            connection = BaseDao.getConnection();
            //通过业务层调用具体的数据库操作
            user = userDao.getLoginUser(connection, userCode);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            BaseDao.closeResource(connection,null,null);
        }
        return user;
    }
//    @Test
//    public void test(){
//        UserServiceImpl userService = new UserServiceImpl();
//        User admin = userService.login("admin", "1234567");
//        System.out.println(admin.getUserPassword());
//    }
}

7.编写servlet

package com.jibu.servlet.user;

import com.jibu.pojo.User;
import com.jibu.service.user.UserService;
import com.jibu.service.user.UserServiceImpl;
import com.jibu.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 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("LoginServlet--start...");

        //获取用户名和密码
        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；
        UserService userService = new UserServiceImpl();
        User user = userService.login(userCode, userPassword); //这里已经把登录的人给查出来了

        if (user!=null){//查有此人，可以登录
            //将用户的信息放到Session中
            req.getSession().setAttribute(Constants.USER_SESSION,user);
            //跳转到主页
            resp.sendRedirect("jsp/frame.jsp");
        }else {//查无此人，无法登录
            //转发会登录页面，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);
        }
    }

    @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.jibu.servlet.user.LoginServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LoginServlet</servlet-name>
        <url-pattern>/login.do</url-pattern>
    </servlet-mapping>

9.测试访问，确保以上功能成功！

登录功能优化 

注销功能：

思路：一处Session，返回登录页面

package com.jibu.servlet.user;

import com.jibu.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：Constants.USER_SESSION
        req.getSession().removeAttribute(Constants.USER_SESSION);
        resp.sendRedirect("/login.jsp");//返回登录页面
    }

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

注销XML

    <servlet>
        <servlet-name>LogoutServlet</servlet-name>
        <servlet-class>com.jibu.servlet.user.LogoutServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LogoutServlet</servlet-name>
        <url-pattern>/jsp/logout.do</url-pattern>
    </servlet-mapping>

登录拦截器

编写一个过滤器，并注册

package com.jibu.filter;

import com.jibu.pojo.User;
import com.jibu.util.Constants;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class SysFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) resp;

        //过滤器，从Session中获取用户，
        User user = (User) request.getSession().getAttribute(Constants.USER_SESSION);

        if (user!=null){
            // 用户已登录，允许请求继续
            chain.doFilter(req,resp);
        }  else {
            // 用户未登录，重定向到登录页面或显示错误信息
            response.sendRedirect("/smbms/error.jsp");
        }
    }

    @Override
    public void destroy() {

    }
}

    <!--用户登录过滤器-->
    <filter>
        <filter-name>SysFilter</filter-name>
        <filter-class>com.jibu.filter.SysFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>SysFilter</filter-name>
        <url-pattern>/jsp/*</url-pattern>
    </filter-mapping>

测试，登录，注销，权限都要保证OK！

密码修改

1.导入前端素材

<li><a href="${pageContext.request.contextPath }/jsp/pwdmodify.jsp">密码修改</a></li>

2.写项目，建议从底层向上写 

3.UserDao接口

    //修改当前用户密码
    public int updatePwd(Connection connection,int id,int password) throws SQLException;

4.UserDao接口实现类

    //修改当前用户密码
    @Override
    public int updatePwd(Connection connection, int id, int password) throws SQLException {

        PreparedStatement pstm = null;
        int execute = 0;
        if (connection!=null){
            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层

    //根据用户id修改密码
    public boolean updatePwd(int id, int pwd);

6. UserService实现类

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

 7.记得实现复用，需要提取出方法

package com.jibu.servlet.user;

import com.jibu.pojo.User;
import com.jibu.service.user.UserService;
import com.jibu.service.user.UserServiceImpl;
import com.jibu.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;

//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){
        //从Session里面拿ID;
        Object o = req.getSession().getAttribute(Constants.USER_SESSION);
        String newpassword = req.getParameter("newpassword");

        boolean flag = false;

        if (o!=null && newpassword!=null){
            UserService userService = new UserServiceImpl();
            flag = userService.updatePwd(((User) o).getId(), newpassword);
            if (flag){
                req.setAttribute("message","修改密码成功，请退出，使用新密码登录");
                //密码修改成功，移除当前Session
                req.getSession().removeAttribute(Constants.USER_SESSION);
            }else {
                req.setAttribute("message","密码修改失败");
            }
        }else {
            req.setAttribute("message","新密码有问题");
        }
        try {
            req.getRequestDispatcher("pwdmodify.jsp").forward(req,resp);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

    <servlet>
        <servlet-name>UserServlet</servlet-name>
        <servlet-class>com.jibu.servlet.user.UserServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>UserServlet</servlet-name>
        <url-pattern>/jsp/user.do</url-pattern>
    </servlet-mapping>

 8.测试

优化密码修改使用Ajax

1.阿里巴巴的fastjson

    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.61</version>
    </dependency>

2.后台代码修改

//修改密码
    public void updatePwd(HttpServletRequest req, HttpServletResponse resp){

        //从Session里面拿ID;
        Object o = req.getSession().getAttribute(Constants.USER_SESSION);
        String newpassword = req.getParameter("newpassword");

        boolean flag = false;

        if (o!=null && !StringUtils.isNullOrEmpty(newpassword)){
            UserService userService = new UserServiceImpl();
            flag = userService.updatePwd(((User) o).getId(), newpassword);
            if (flag){
                req.setAttribute("message","修改密码成功，请退出，使用新密码登录");
                //密码修改成功，移除当前Session
                req.getSession().removeAttribute(Constants.USER_SESSION);
            }else {
                req.setAttribute("message","密码修改失败");
            }
        }else {
            req.setAttribute("message","新密码有问题");
        }
        try {
            req.getRequestDispatcher("pwdmodify.jsp").forward(req,resp);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    //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<>();
        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();
        }

    }

3.测试 

用户管理实现

思路：

1.导入分页的工具类

2.用户列表页面导入 

userlist.jsp

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

//根据用户名或者角色查询用户总数【最难理解的sql】
    @Override
    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 r where u.userRole = r.id");
            ArrayList<Object> list = new ArrayList<>();//存放我们的参数

            if (!StringUtils.isNullOrEmpty(username)){
                sql.append(" and u.userName like ?");
                list.add("%"+username+"%");//index：0
            }
            if (userRole>0){
                sql.append(" and u.userRole = ?");
                list.add(userRole);//index：1
            }

            //怎么把list转换为数组
            Object[] params = list.toArray();

            System.out.println("UserDaoImpl->getUserCount:"+sql.toString());//输出最后完整的SQL语句

            rs = BaseDao.execute(connection, pstm, rs, sql.toString(), params);

            if (rs.next()){
                count = rs.getInt("count");//从结果集中获取最终的数量
            }
            BaseDao.closeResource(null,pstm,rs);
        }
        return count;
    }

3.UserService

    //查询记录数
    public int getUserCount(String username,int userRole);

3.UserServiceImpl

    //查询记录数
    @Override
    public int getUserCount(String username, int userRole) {

        Connection connection = null;
        int count = 0;
        try {
            connection = BaseDao.getConnection();
            count = userDao.getUserCount(connection, username, userRole);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            BaseDao.closeResource(connection,null,null);
        }
        return count;
    }

2、获取用户列表

1.UserDao

//通过条件查询-userList
public List<User> getUserList(Connection connection, String userName, int userRole, int currentPageNo, int pageSize)throws Exception;

2.UserDaoImpl

    @Override
    public List<User> getUserList(Connection connection, String userName, int userRole, int currentPageNo, int pageSize) throws Exception {
        // TODO Auto-generated method stub
        PreparedStatement pstm = null;
        ResultSet rs = null;
        List<User> userList = new ArrayList<User>();
        if(connection != null){
            StringBuffer sql = new StringBuffer();
            sql.append("select u.*,r.roleName as userRoleName from smbms_user u,smbms_role r where u.userRole = r.id");
            List<Object> list = new ArrayList<Object>();
            if(!StringUtils.isNullOrEmpty(userName)){
                sql.append(" and u.userName like ?");
                list.add("%"+userName+"%");
            }
            if(userRole > 0){
                sql.append(" and u.userRole = ?");
                list.add(userRole);
            }

            //在数据库中分页使用 limit startIndex，pageSize; 总数
            //0,5       1
            //5,5
            //10,5

            sql.append(" order by creationDate DESC limit ?,?");
            currentPageNo = (currentPageNo-1)*pageSize;
            list.add(currentPageNo);
            list.add(pageSize);

            Object[] params = list.toArray();
            System.out.println("sql ----> " + sql.toString());
            rs = BaseDao.execute(connection, pstm, rs, sql.toString(), params);
            while(rs.next()){
                User _user = new User();
                _user.setId(rs.getInt("id"));
                _user.setUserCode(rs.getString("userCode"));
                _user.setUserName(rs.getString("userName"));
                _user.setGender(rs.getInt("gender"));
                _user.setBirthday(rs.getDate("birthday"));
                _user.setPhone(rs.getString("phone"));
                _user.setUserRole(rs.getInt("userRole"));
                _user.setUserRoleName(rs.getString("userRoleName"));
                userList.add(_user);
            }
            BaseDao.closeResource(null, pstm, rs);
        }
        return userList;
    }

3.UserService

//根据条件查询用户列表
public List<User> getUserList(String queryUserName, int queryUserRole, int currentPageNo, int pageSize);

4.UserSeviceImpl

    @Override
    public List<User> getUserList(String queryUserName, int queryUserRole, int currentPageNo, int pageSize) {
        // TODO Auto-generated method stub
        Connection connection = null;
        List<User> userList = null;
        System.out.println("queryUserName ---- > " + queryUserName);
        System.out.println("queryUserRole ---- > " + queryUserRole);
        System.out.println("currentPageNo ---- > " + currentPageNo);
        System.out.println("pageSize ---- > " + pageSize);
        try {
            connection = BaseDao.getConnection();
            userList = userDao.getUserList(connection, queryUserName,queryUserRole,currentPageNo,pageSize);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            BaseDao.closeResource(connection, null, null);
        }
        return userList;
    }

3、获取角色操作

为了我们职责统一，可以把角色的操作单独放在一个包中，和POJO类对应

1.RoleDao 

package com.jibu.dao.role;

import com.jibu.pojo.Role;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

public interface RoleDao {
    //获取角色列表
    public List<Role> getRoleList(Connection connection) throws SQLException;
}

2.RoleDaoImpl 

package com.jibu.dao.role;

import com.jibu.dao.BaseDao;
import com.jibu.pojo.Role;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class RoleDaoImpl implements RoleDao{
    //获取角色列表
    @Override
    public List<Role> getRoleList(Connection connection) throws SQLException {

        PreparedStatement pstm = null;
        ResultSet resultSet = null;
        ArrayList<Role> roleList = new ArrayList<>();

        if (connection != null){
            String sql = "select * from smbms_role";
            Object[] params = {};
            resultSet = BaseDao.execute(connection, pstm, resultSet, sql, params);

            while (resultSet.next()){
                Role _role = new Role();
                _role.setId(resultSet.getInt("id"));
                _role.setRoleCode(resultSet.getString("userCode"));
                _role.setRoleName(resultSet.getString("userName"));
                roleList.add(_role);
            }
            BaseDao.closeResource(null,pstm,resultSet);
        }
        return roleList;
    }
}

3.RoleService 

package com.jibu.service.role;

import com.jibu.pojo.Role;

import java.util.List;

public interface RoleService {
    //获取角色列表
    public List<Role> getRoleList();
}

 4.RoleServiceImpl

package com.jibu.service.role;

import com.jibu.dao.BaseDao;
import com.jibu.dao.role.RoleDao;
import com.jibu.dao.role.RoleDaoImpl;
import com.jibu.pojo.Role;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

public class RoleServiceImpl implements RoleService{

    //引入Dao
    private RoleDao roleDao;
    public RoleServiceImpl() {
        roleDao = new RoleDaoImpl();
    }

    @Override
    public List<Role> getRoleList() {

        Connection connection = null;
        List<Role> roleList = null;
        try {
            connection = BaseDao.getConnection();
            roleList = roleDao.getRoleList(connection);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            BaseDao.closeResource(connection,null,null);
        }
        return roleList;
    }
}

4、用户显示的Servlet

1.获取用户前端的数据（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，需要计算出当前页面和总页面，页面大小

4.用户列表展示

5.返回前端

    //重点、难点
    public void query(HttpServletRequest req, HttpServletResponse resp){

        //查询用户列表

        //从前端获取数据
        String queryUserName = req.getParameter("queryname");
        String temp = req.getParameter("queryUserRole");
        String pageIndex = req.getParameter("pageIndex");
        int queryUserRole = 0;

        //获取用户列表
        UserServiceImpl userService = new UserServiceImpl();
        List<User> userList = null;

        //第一次走这个请求一定是第一页，并且页面大小是固定的
        int pageSize = 5;//可以把这个写到配置文件里，方便后期修改；
        int currentPageNo = 1;

        if (queryUserName == null){
            queryUserName = "";
        }
        if (temp!=null && !temp.equals("")){
            queryUserRole = Integer.parseInt(temp); //给查询赋值
        }
        if (pageIndex!=null){
            currentPageNo = Integer.parseInt(pageIndex);
        }

        //获取用户的总数(分页：   上一页，下一页的情况)
        int totalCount = userService.getUserCount(queryUserName, queryUserRole);
        //总页数支持
        PageSupport pageSupport = new PageSupport();
        pageSupport.setCurrentPageNo(currentPageNo);
        pageSupport.setPageSize(pageSize);
        pageSupport.setTotalCount(totalCount);

        int totalPageCount = pageSupport.getTotalPageCount();//最大页数

        //控制首页和尾页
        //如果页面要小于1了，就显示第一页的东西
        if (totalPageCount<1){
            totalPageCount = 1;
        } else if (currentPageNo>totalPageCount) {//当前页面大于了最后一页；
            currentPageNo = totalPageCount;
        }

        //获取用户列表展示
        userList = userService.getUserList(queryUserName, queryUserRole, currentPageNo, pageSize);
        req.setAttribute("userList",userList);

        RoleServiceImpl roleService = new RoleServiceImpl();
        List<Role> roleList = roleService.getRoleList();
        req.setAttribute("roleList",roleList);
        req.setAttribute("totalCount",totalCount);
        req.setAttribute("currentPageNo",currentPageNo);
        req.setAttribute("totalPageCount",totalPageCount);
        req.setAttribute("queryUserName",queryUserName);
        req.setAttribute("queryUserRole",queryUserRole);

        //返回前端
        try {
            req.getRequestDispatcher("userlist.jsp").forward(req,resp);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

小黄鸭调试法