smbms(超市管理系统)源码 + 分析

在项目开始之前，我们首先要对项目的整体架构分析一下，该项目一共分为四个模块，登录注销、用户管理、订单管理、供应商管理，其中用户管理、订单管理以及供应商管理都是需要对数据库进行crud的。项目的整体架构图如下：

项目的架构分析完成之后，我们首先就需要进行一些前期准备，创建项目。首先创建一个Maven项目：

在Maven项目创建完毕之后，我们需要对配置文件进行修改

对web.xml的修改如下：

对pom.xml进行配置，导入相关的依赖如下：

  4.0.0

    org.example
    smbms
    1.0-SNAPSHOT
    war
    
        
            junit
            junit
            4.12
        
        
            org.apache.tomcat
            tomcat-servlet-api
            10.0.16
        


        
            com.alibaba
            fastjson
            1.2.79
        
        
            mysql
            mysql-connector-java
            8.0.25
        
        
            org.apache.tomcat
            tomcat-jsp-api
            10.0.16
        
        
            org.glassfish.web
            jakarta.servlet.jsp.jstl
            2.0.0
        


  

将Maven配置完成后，我们需要对Tomcat进行配置：

Tomcat配置完成之后，我们需要连接数据库

实体类中的四个类是与数据库当中的四个表相对应的。

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;
    }
}

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;
    }


}

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 long 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;
    }


}

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 Integer getAge(){
        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;
    }


    public void setAge(Integer age) {
        this.age = age;
    }

    public String getUserRoleName() {
        return userRoleName;
    }

    public void setUserRoleName(String userRoleName) {
        this.userRoleName = userRoleName;
    }

    public User(){

    }

    public void setUserName(Object userName) {
    }
}

因为我们每一个模块都会涉及到对数据库的crud，以及对数据库的资源的连接和关闭。是一个有着大量重复性的操作，所以我们需要编写一个公共类来实现这些操作，这样在编写每一个模块的时候就可以直接调用。

public class baseDao {
    private static String url;
    private static String driver;
    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 {
        //通过类加载器读取响应的资源
        Properties properties = new Properties();
        InputStream is = baseDao.class.getClassLoader().getResourceAsStream("database.properties");

        try {
            properties.load(is);
        } catch (IOException e) {
            e.printStackTrace();
        }
        url = properties.getProperty("url");
        driver = properties.getProperty("driver");
        username = properties.getProperty("username");
        password = properties.getProperty("password");
    }
    //获得数据库的链接
    public static Connection getConnection() {
        Connection connection = null;
        try {
            Class.forName(driver);
            connection = DriverManager.getConnection(url, username, password);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return connection;
    }
    
    //执行sql查询语句
    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++) {
            preparedStatement.setObject(i + 1, params[i]);
        }
        resultSet = preparedStatement.executeQuery();
        return resultSet;
    }


    //对数据库进行crud
    public static int execute(Connection connection, String sql, Object[] params, PreparedStatement preparedStatement) throws SQLException {
        preparedStatement = connection.prepareStatement(sql);
        for (int i = 0; i < params.length; i++) {
            preparedStatement.setObject(i + 1, params[i]);
        }
        int updateRows = preparedStatement.executeUpdate();
        System.out.println(updateRows);
        return updateRows;
    }

    //关闭数据库资源
    public static boolean close(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet) {
        boolean flag = true;
        if (resultSet != null) {
            try {
                resultSet.close();
                resultSet = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        if (preparedStatement != null) {
            try {
                preparedStatement.close();
                preparedStatement = null;
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (connection != null) {
            try {
                connection.close();
                connection = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        return flag;
    }
}

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

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

    }

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        servletRequest.setCharacterEncoding("utf-8");
        servletResponse.setCharacterEncoding("utf-8");

        filterChain.doFilter(servletRequest, servletResponse);
    }

    public void destroy() {
    }
}

编写了过滤器之后，我们还需要到web.xml中去注册才能实现过滤功能

    filter
    com.zhou.filter.CharacterEncodingFilter



    filter
    
    public User getLoginUser(String userCode, String password);
    
    public User getLoginUser(String userCode);

    
    public boolean updatePwd(int id,String pwd);

    
    public int getUserNums(String username,int userRole);

    
    public List getUserList(String username,int userRole,int currentPageNo,int pageSize);

    
    public boolean add(User user);

    
    public boolean modify(User user);

    
    public User getUserById(String id);

    
    public boolean delUser(int id);

}

package com.zhou.service.user;

import com.zhou.dao.baseDao;
import com.zhou.dao.user.UserDao;
import com.zhou.dao.user.UserDaoImp;
import com.zhou.polo.User;

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

public class UserServiceImp implements UserService{
    private UserDao userdao;
    public UserServiceImp(){
        userdao = new UserDaoImp();
    }
    public User getLoginUser(String userCode, String password) {
        Connection connection = null;
        User user = null;
        try {
            //获取与数据库的连接
            connection = baseDao.getConnection();
            //获取用户
            user = userdao.getLoginUser(connection,userCode,password);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            //关闭连接
            baseDao.close(connection,null,null);
        }
        return user;
    }

    @Override
    public User getLoginUser(String userCode) {
        Connection connection = null;
        User user = null;
        try {
            //获取与数据库的连接
            connection = baseDao.getConnection();
            //获取用户
            user = userdao.getLoginUser(connection,userCode);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            //关闭连接
            baseDao.close(connection,null,null);
        }
        return user;
    }

    public boolean updatePwd(int id, String pwd) {
        Connection connection = null;
        boolean flag = false;
        try {
            connection = baseDao.getConnection();
            flag = userdao.updatePwd(connection,id,pwd);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            baseDao.close(connection,null,null);
        }
        return flag;
    }

    @Override
    public int getUserNums(String username, int userRole) {
        Connection connection = null;
        int count = 0;
        connection = baseDao.getConnection();
        if(connection != null){
            try {
                count = userdao.getUserNums(connection,username,userRole);
            } catch (SQLException e) {
                e.printStackTrace();
            }finally{
                baseDao.close(connection,null,null);
            }
        }
        return count;
    }

    @Override
    public List getUserList(String username, int userRole, int currentPageNo, int pageSize) {
        Connection connection = null;
        List userList = null;
        connection = baseDao.getConnection();
        if(connection != null){
            try {
                userList = userdao.getUserList(connection,username,userRole,currentPageNo,pageSize);
            } catch (SQLException e) {
                e.printStackTrace();
            }finally{
                baseDao.close(connection,null,null);
            }
        }
        return userList;
    }

    @Override
    public boolean add(User user) {
        boolean flag = false;
        Connection connection = null;
        try {

            connection = baseDao.getConnection();
            //开启jdbc的事务管理，同时设置自动提交为false
            System.out.println("1");
            connection.setAutoCommit(false);
            System.out.println("2");
            flag = userdao.add(connection,user);
            System.out.println("3");
            connection.commit();
            System.out.println("4");
            if(flag){
                System.out.println("add success!");
            }else{
                System.out.println("add failed!");
            }
        } catch (SQLException e) {
            System.out.println("rollback------------");
            try {
                connection.rollback();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
            e.printStackTrace();
        } finally {
            baseDao.close(connection,null,null);
        }
        return flag;
    }

    @Override
    public boolean modify(User user) {
        boolean flag = false;
        Connection connection = null;
        if(user != null){
            connection = baseDao.getConnection();
            try {
                flag = userdao.modify(connection, user);
            } catch (SQLException e) {
                e.printStackTrace();
            }finally{
                baseDao.close(connection,null,null);
            }
        }
        return flag;
    }

    @Override
    public User getUserById(String id) {
        User user = null;
        Connection connection = null;
        connection = baseDao.getConnection();
        if(connection != null){
            try {
                user = userdao.getUserById(connection, id);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        baseDao.close(connection,null,null);
        return user;
    }

    @Override
    public boolean delUser(int id) {
        boolean flag = false;
        Connection connection = baseDao.getConnection();
        if(connection != null){
            try {
                flag = userdao.delUser(connection, id);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        baseDao.close(connection,null,null);

        return flag;
    }

}

package com.zhou.servlet.user;

import com.alibaba.fastjson.JSONArray;
import com.mysql.cj.util.StringUtils;
import com.zhou.polo.Role;
import com.zhou.polo.User;
import com.zhou.service.role.RoleServiceImpl;
import com.zhou.service.user.UserService;
import com.zhou.service.user.UserServiceImp;
import com.zhou.util.Constants;
import com.zhou.util.PageSupport;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

import java.io.IOException;
import java.io.PrintWriter;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;


public class UserServlet extends HttpServlet {

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

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获得前端的method信息实现对应的功能
        String method = req.getParameter("method");
        System.out.println("Usermethod --> " + method);
        if(method != null && method.equals("savepwd")){
            this.updatePwd(req,resp);
        }else if(method != null && method.equals("pwdmodify")){
            this.pwdModify(req,resp);
        }else if(method != null && method.equals("query")){
            this.query(req,resp);
        }else if(method != null && method.equals("add")){
            this.add(req,resp);
        }else if(method != null && method.equals("getrolelist")){
            this.getRoleList(req,resp);
        }else if(method != null && method.equals("modifyexe")){
            this.modify(req,resp);
        }else if(method != null && method.equals("modify")){
            this.getUserById(req,resp,"usermodify.jsp");
        }else if(method != null && method.equals("view")){
            this.getUserById(req,resp,"userview.jsp");
        }else if(method != null && method.equals("deluser")){
            this.delUser(req,resp);
        }else if(method != null && method.equals("ucexist")){
            this.isUserCodeExist(req,resp);
        }
    }

    public void isUserCodeExist(HttpServletRequest req, HttpServletResponse resp) {
        String userCode = req.getParameter("userCode");
        Map resultMap = new HashMap<>();
        if(StringUtils.isNullOrEmpty(userCode)){
            resultMap.put("userCode","exist");
        }else{
            UserService userService = new UserServiceImp();
            User user = userService.getLoginUser(userCode);
            if(user != null){
                resultMap.put("userCode","exist");
            }else{
                resultMap.put("userCode","notexist");
            }
        }
        //将resultMap转换成json对象输出
        resp.setContentType("application/json");
        try {
            PrintWriter writer = resp.getWriter();
            writer.write(JSONArray.toJSONString(resultMap));
            writer.flush();
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void delUser(HttpServletRequest req, HttpServletResponse resp){
        String id = req.getParameter("uid");
        int delId;
        if(!StringUtils.isNullOrEmpty(id)){
            delId = Integer.parseInt(id);
        }else{
            delId = 0;
        }
        Map resultMap = new HashMap<>();
        if(delId <= 0){
            resultMap.put("delResult","notexist");
        }else {
            UserService userService = new UserServiceImp();
            if(userService.delUser(delId)){
                resultMap.put("delResult","true");
            }else{
                resultMap.put("delResult","false");
            }
        }
        //把resultMap转换成json对象输出
        resp.setContentType("application/json");
        PrintWriter writer = null;
        try {
            writer = resp.getWriter();
            writer.write(JSONArray.toJSONString(resultMap));
            writer.flush();
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public void modify(HttpServletRequest req, HttpServletResponse resp){
        String id = req.getParameter("uid");
        String userName = req.getParameter("userName");
        String gender = req.getParameter("gender");
        String birthday = req.getParameter("birthday");
        String phone = req.getParameter("phone");
        String address = req.getParameter("address");
        String userRole = req.getParameter("userRole");

        User user = new User();
        user.setId(Integer.valueOf(id));
        user.setUserName(userName);
        user.setGender(Integer.valueOf(gender));
        try {
            user.setBirthday(new SimpleDateFormat("yyyy-MM-dd").parse(birthday));
        } catch (ParseException e) {
            e.printStackTrace();
        }
        user.setPhone(phone);
        user.setAddress(address);
        user.setUserRole(Integer.valueOf(userRole));
        user.setCreationDate(new Date());
        user.setModifyBy(((User)req.getSession().getAttribute(Constants.USER_SESSION)).getId());

        UserService userService = new UserServiceImp();
        if(userService.modify(user)){
            try {
                resp.sendRedirect(req.getContextPath() + "/jsp/user.do?method=query");
            } catch (IOException e) {
                e.printStackTrace();
            }
        }else{
            try {
                req.getRequestDispatcher("usermodify.jsp").forward(req,resp);
            } catch (ServletException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    //获取用户id
    public void getUserById(HttpServletRequest req, HttpServletResponse resp,String url){
        String  id = req.getParameter("uid");
        if(!StringUtils.isNullOrEmpty(id)){
            UserService userService = new UserServiceImp();
            User user = userService.getUserById(id);
            req.setAttribute("user",user);
            try {
                req.getRequestDispatcher(url).forward(req,resp);
            } catch (ServletException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    public void getRoleList(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        List roleList = null;
        RoleServiceImpl roleService = new RoleServiceImpl();
        roleList = roleService.getRoleList();
        //把RoleList转换成json对象输出
        resp.setContentType("application/json");
        PrintWriter writer = resp.getWriter();
        writer.write(JSONArray.toJSONString(roleList));
        writer.flush();
        writer.close();
    }

    //修改密码
    public void updatePwd(HttpServletRequest req, HttpServletResponse resp){
        //从Session中拿Id
        Object id = req.getSession().getAttribute(Constants.USER_SESSION);
        String npwd = req.getParameter("newpassword");
        boolean flag = false;
        if(id != null && !StringUtils.isNullOrEmpty(npwd)){
            UserService userService = new UserServiceImp();
            flag = userService.updatePwd(((User)id).getId(), npwd);
            if(flag){
                req.setAttribute("message","密码修改成功,请退出,使用新密码登录");
                //密码修改成功，移除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();
        }
    }

    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");

        Map resultMap = new HashMap<>();

        if(o != null){  // Session失效
            resultMap.put("result","sessionerror");
        }if(StringUtils.isNullOrEmpty(oldpassword)){
            resultMap.put("result","error");
        }else{
            String userpassword = ((User)o).getUserPassword();      //获取Session中用户的密码
            if(userpassword.equals(oldpassword)){
                resultMap.put("result","true");
            }else{
                resultMap.put("result","false");
            }
        }

        try {
            resp.setContentType("application/json");
            PrintWriter writer = resp.getWriter();
            writer.write(JSONArray.toJSONString(resultMap));
            writer.flush();
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
    //查询对应的用户信息
    public void query(HttpServletRequest req, HttpServletResponse resp){
        //从前端获取数据
        String queryUserName = req.getParameter("queryUserName");
        String temp = req.getParameter("queryUserRole");
        String pageIndex = req.getParameter("pageIndex");
        int queryUserRole = 0;

        //获取用户列表
        UserServiceImp userServiceImp = new UserServiceImp();

        //第一次走请求肯定是第一页，页面大小固定
        int pageSize = 5;   //可以把属性写到配置文件当中，方便修改
        int currentPageNo = 1;

        if(queryUserName == null){
            queryUserName = "";
        }
        if(temp != null && !temp.equals("")){
            queryUserRole = Integer.parseInt(temp);     //给查询赋值1,2,3
        }
        if(pageIndex != null){
            currentPageNo = Integer.parseInt(pageIndex);
        }

        //获取用户的总数
        int totalCount = userServiceImp.getUserNums(queryUserName,queryUserRole);
        //总页数
        PageSupport pageSupport = new PageSupport();
        pageSupport.setCurrentPageNo(currentPageNo);        //设置当前页数
        pageSupport.setPageSize(pageSize);                  //设置页数记录数
        pageSupport.setTotalCount(totalCount);              //设置所有记录数目

        int totalPageCount = ((int) (totalCount / pageSize)) + 1;
        //控制尾页和首页
        if(currentPageNo < 1){
            currentPageNo = 1;
        }else if (currentPageNo > totalPageCount){    //控制尾页
            currentPageNo = totalPageCount;
        }

        //获取用户列表显示
        List userList = userServiceImp.getUserList(queryUserName,queryUserRole,currentPageNo,pageSize);
        req.setAttribute("userList",userList);

        RoleServiceImpl roleService = new RoleServiceImpl();
        List roleList = roleService.getRoleList();
        req.setAttribute("roleList",roleList);
        req.setAttribute("totalCount",totalCount);
        req.setAttribute("currentPageNo",currentPageNo);
        req.setAttribute("queryUserName",queryUserName);
        req.setAttribute("queryUserRole",queryUserRole);
        req.setAttribute("totalPageCount",totalPageCount);
        //返回前端
        try {
            req.getRequestDispatcher("userlist.jsp").forward(req,resp);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    //用户添加
    public void add(HttpServletRequest req, HttpServletResponse resp){
        String userCode = req.getParameter("userCode");
        String userName = req.getParameter("userName");
        String userPassword = req.getParameter("userPassword");
        String gender = req.getParameter("gender");
        String birthday = req.getParameter("birthday");
        String userRole = req.getParameter("userRole");
        String address = req.getParameter("address");
        String phone = req.getParameter("phone");

        boolean flag = false;
        User user = new User();
        user.setUserCode(userCode);
        user.setUserName(userName);
        user.setUserPassword(userPassword);
        user.setGender(Integer.parseInt(gender));
        try {
            user.setBirthday(new SimpleDateFormat("yyyy-MM-dd").parse(birthday));
        } catch (ParseException e) {
            e.printStackTrace();
        }
        user.setUserRole(Integer.parseInt(userRole));
        user.setAddress(address);
        user.setPhone(phone);
        user.setCreationDate(new Date());
        user.setCreatedBy(((User)(req.getSession().getAttribute(Constants.USER_SESSION))).getId());

        UserServiceImp userServiceImp = new UserServiceImp();
        flag = userServiceImp.add(user);
        if(flag){
            try {
                resp.sendRedirect(req.getContextPath() + "/jsp/user.do?method=query");
            } catch (IOException e) {
                e.printStackTrace();
            }
        }else{
            try {
                req.getRequestDispatcher("useradd.jsp").forward(req,resp);
            } catch (ServletException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }
}

与用户管理的功能一样，因此直接展示代码

package com.zhou.dao.provider;

import com.zhou.polo.Provider;

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


public interface ProviderDao {
    
    public List getProviderList(Connection connection,String providerCode,String providerName) throws SQLException;

    
    public boolean add(Connection connection,Provider provider) throws SQLException;
    
    public boolean delProvider(Connection connection,int id ) throws SQLException;
    
    public Provider getProviderById(Connection connection,String id) throws SQLException;

    
    public boolean modify(Connection connection,Provider provider) throws SQLException;
}

package com.zhou.dao.provider;

import com.mysql.cj.util.StringUtils;
import com.zhou.dao.baseDao;
import com.zhou.polo.Provider;

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 ProviderDaoImpl implements ProviderDao{

    @Override
    public List getProviderList(Connection connection, String providerCode, String providerName) throws SQLException {
        List providerList = null;
        ResultSet rs = null;
        PreparedStatement pstm = null;
        if(connection != null){
            StringBuffer sql = new StringBuffer();
            providerList = new ArrayList<>();
            List