SMBMS

SMBMS

项目如何搭建：可使用maven

一，项目搭建

1，搭建一个maven web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

<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>2.0</version>
</dependency>
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>5.1.32</version>
</dependency>
<dependency>
   <groupId>javax.servlet.jsp.jstl</groupId>
   <artifactId>jstl-api</artifactId>
   <version>1.2</version>
 </dependency>
 <dependency>
    <groupId>taglibs</groupId>
    <artifactId>standard</artifactId>
    <version>1.1.2</version>
  </dependency>

5，创建项目包结构

6，编写实体类：

ORM映射：表——类映射

User类

package com.fan.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() {
        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;
    }

}

Role类

package com.fan.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;
    }
}

Provider类

package com.fan.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;
    }
}

Bill类

package com.fan.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;
    }
}

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

2,在dao包建立BaseDao类

package com.fan.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("");
        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;
    }
    //编写查询公共类
    public static ResultSet excute(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 excute(Connection connection,String sql,Object[] params,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();
                //垃圾回收
                resultSet = null;
            } catch (SQLException e) {
                 e.printStackTrace();
                 flag = false;
            }
        }
        if (preparedStatement!=null){
            try {
                preparedStatement.close();
                //垃圾回收
                preparedStatement = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        if (connection!=null){
            try {
                connection.close();
                //垃圾回收
                connection = null;
            } catch (SQLException e) {
                e.printStackTrace();
                flag = false;
            }
        }
        return flag;
    }

}

3.编写字符编码过滤器

在filter中建立CharacterEncodingFilter类

package com.fan.filter;

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

public class CharacterEncodingFilter implements Filter {

    public void init(FilterConfig filterConfig) throws ServletException {

    }

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

    public void destroy() {

    }
}

在web.xml中注册

<!--注册字符编码过滤器-->
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>com.fan.filter.CharacterEncodingFilter</filter-class>
    </filter>
   <filter-mapping>
       <filter-name>CharacterEncodingFilter</filter-name>
<!--/*所有请求都会被过滤 -->
       <url-pattern>/*</url-pattern>
   </filter-mapping>

8，导入静态资源

导入到web-app文件夹中

实现登录功能

（1）编写前端页面

login.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title>系统登录 - 超市订单管理系统</title>
    <link type="text/css" rel="stylesheet" href="${pageContext.request.contextPath }/css/style.css" />
    <script type="text/javascript">
    </script>
</head>
<body class="login_bg">
<section class="loginBox">
    <header class="loginHeader">
        <h1>超市订单管理系统</h1>
    </header>
    <section class="loginCont">
        <form class="loginForm" action="${pageContext.request.contextPath }/login.do"  name="actionForm" id="actionForm"  method="post" >
            <div class="info">${error }</div>
            <div class="inputbox">
                <label >用户名：</label>
                <input type="text" class="input-text" id="userCode" name="userCode" placeholder="请输入用户名" required/>
            </div>
            <div class="inputbox">
                <label >密码：</label>
                <input type="password" id="userPassword" name="userPassword" placeholder="请输入密码" required/>
            </div>
            <div class="subBtn">

                <input type="submit" value="登录"/>
                <input type="reset" value="重置"/>
            </div>
        </form>
    </section>
</section>
</body>
</html>

(2)将login.jsp设置为首页，在web.xml 中写

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

（3）编写dao层用户登录的接口：在dao中建立一个user包，在包中建一个UserDao接口，在接口中写 。

package com.fan.dao.user;
import com.fan.pojo.User;
import java.sql.Connection;
import java.sql.SQLException;

public interface UserDao {
    //得到登录的用户
    public User getLoginUser(Connection connection,String userCode) throws SQLException;
}

（4）编写UserDao接口的实现类UserDaoImpl

package com.fan.dao.user;

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

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

public class UserDaoImpl  implements UserDao{
    //得到登录的用户
    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 user where userCode=?";
            Object[] params = {userCode};

                rs = BaseDao.excute(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）编写业务层接口

在service下建立user包，建立UserService接口

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

(6)编写业务层接口的实现类

在service的user包中建立UserServiceImpl类 

package com.fan.service.user;
import com.fan.dao.BaseDao;
import com.fan.dao.user.UserDao;
import com.fan.dao.user.UserDaoImpl;
import com.fan.pojo.User;
import org.junit.Test;
import javax.jws.soap.SOAPBinding;
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();
    }

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

        try {
            connection = BaseDao.getConnection();//得到连接
            //通过业务层调用对应的具体的数据库操作
            user = userDao.getLoginUser(connection, userCode);
            //z做查询
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            BaseDao.closeResource(connection, null, null);//关闭资源
        }
        return user;//调用这个login方法的，就可以拿到user
    }

}

（7）编写Servlet类

在Servlet包中创建user包，在user包中建立LoginServlet类 

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
        System.out.println(userCode);
        System.out.println(userPassword);
        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
            //转发回登录页面，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);
    }
}

在web.xml中注册

<servlet>
    <servlet-name>LoginServlet</servlet-name>
    <servlet-class>com.kuang.servlet.user.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>LoginServlet</servlet-name>
    <url-pattern>/login.do</url-pattern>
</servlet-mapping>

在util包中创建专门存放常量的Constants

package com.fan.util;

public class Constants {
    public final static String USER_SESSION = "userSession";
}

二，注销

在Servlet包的user包中建立LogoutServlett类

public class LogoutServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //移除用户的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);
    }
}

在web.xml中注册

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

设置自动注销

设置30分后session自动失效

<session-config>
   <session-timeout>30</session-timeout>
</session-config>

三，登录拦截

在filter中建立SysFilter类 

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

    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){ //已经被移除或者注销了，或者未登录
            response.sendRedirect("/error.jsp");
        }else {
            chain.doFilter(req,resp);
        }
    }

    public void destroy() {

    }
}

在web.xml中注册 

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

四，密码修改的实现

1.编写dao层用户修改密码的接口UserDao

UserDao接口写如下代码 

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

2.编写UserDao 接口实现类UserDaoImpl

 public int updatePwd(Connection connection, int id, String 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, sql, params, pstm);
            BaseDao.closeResource(null,pstm,null);
        }

        return execute;
    }

3.编写业务层接口

在service的user包中的UserService接口中添加如下代码

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

4.编写业务层接口实现类

在service的user包中的UserServiceImpl类中添加以下代码 

public boolean updatePwd(int id, String 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;
    }

5.编写Servlet类

在Servlet包中的user包中建立UserServlet类

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);
        }else if (method.equals("pwdmodify")){
            this.pwdModify(req, resp);
        }
    }

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

    //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");

        System.out.println("UserServlet:"+newpassword);

        boolean flag = false;

        System.out.println(o!=null);
        System.out.println(StringUtils.isNullOrEmpty(newpassword));

        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");
                //密码修改成功，移除当前Session
            }
        }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");
        System.out.println(oldpassword);
        //万能的Map : 结果集
        Map<String, String> resultMap = new HashMap<String,String>();

        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();
        }

    }
}

在web.xml中注册

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

三.用户管理实现

1.获取用户数量

（1）编写查询总人数的接口UserDao

UserDao接口写如下代码 

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

（2）UserDao接口实现类UserDaoImpl

向实现类中添加以下代码

public int getUserCount(Connection connection, String username, int userRole) throws SQLException {
        //根据用户名或者角色查询用户总数

        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<Object>();//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）编写业务层接口

在service的user包中的UserService接口中添加如下代码 

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

（4）编写业务层接口实现类

在service的user包中的UserServiceImpl类中添加以下代码 

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）编写UserDao

UserDao接口写如下代码 

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

（2）UserDao接口实现类UserDaoImpl

向实现类中添加以下代码 

 public List<User> getUserList(Connection connection, String userName,int userRole,int currentPageNo, int pageSize)
            throws Exception {
        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);
            }
            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）编写业务层接口

在service的user包中的UserService接口中添加如下代码 

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

（4）编写业务层接口实现类

在service的user包中的UserServiceImpl类中添加以下代码 

 public List<User> getUserList(String queryUserName, int queryUserRole, int currentPageNo, int pageSize) {
        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) {
            e.printStackTrace();
        }finally{
            BaseDao.closeResource(connection, null, null);
        }
        return userList;
    }

3.获取角色操作

（1）编写接口RoleDao

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

（2）RoleDao接口实现类RoleDaoImpl

向实现类中添加以下代码 

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

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

        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("roleCode"));
                _role.setRoleName(resultSet.getString("roleName"));
                roleList.add(_role);
            }
            BaseDao.closeResource(null,pstm,resultSet);
        }
        return roleList;
    }
}

（3）编写业务层接口

在service建立role包，然后建立RoleService接口，添加如下代码 

 //获取角色列表
public List<Role> getRoleList();

（4）编写业务层接口实现类

在service的role包中的RoleServiceImpl类中添加以下代码 

public class RoleServiceImpl implements RoleService {

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

    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.编写Servlet类

对Servlet包中的user包中UserServlet类进行如下添加 

//添加一个if判断
@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);
        }else if (method.equals("pwdmodify")&&method!=null){
            this.pwdModify(req, resp);
        }else if (method.equals("query")&&method!=null){
            this.query(req, resp);

        }
    }

    //query方法
    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，页面大小固定的；
        int pageSize = 5; //可以把这个些到配置文件中，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！0,1,2,3
        }
        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 = ((int)(totalCount/pageSize))+1;

        //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 (currentPageNo<1){
            currentPageNo = 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();
        }
    }