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JavaWeb-SMBMS(超市管理项目)

时间：2022-10-02 12:33:23浏览次数：78  
标签：JavaWeb int req 超市 connection SMBMS user null public

目录

SMBMS(超市管理项目)

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数据库：

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项目如何搭建？
考虑是不是用maven？ jar包，依赖

搭建项目准备工作

smbms项目静态资源+数据库下载 密码:smbms

  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. 导入项目中需要的jar包;
    jsp，Servlet，mysql驱动，jstl，stand…

    <dependencies>
    <!--servlet与jsp依赖-->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet.jsp</groupId>
        <artifactId>javax.servlet.jsp-api</artifactId>
        <version>2.3.3</version>
    </dependency>
    <!--mysql驱动依赖-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.30</version>
    </dependency>
    <!--jstl依赖与standard标签库-->
    <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>
</dependencies>

  5. 构建项目包结构

    在这里插入图片描述

  6. 编写实体类
    ROM映射:表-类映射

    在这里插入图片描述

    在这里插入图片描述

    在这里插入图片描述

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  7. 编写基础公共类

    1、数据库配置文件（mysql5.xx和8.xx的编写有差异）

    在Tomcat服务器lib目录下也要导mysql-connector-java.jar包

    db.properties：

    #mysql8.xx    com.mysql.cj.jdbc.Driver
#mysql5.xx    com.mysql.jdbc.Driver
driver=com.mysql.cj.jdbc.Drive
#在和mysql传递数据的过程中，使用unicode编码格式，并且字符集设置为utf-8
url=jdbc:mysql://localhost:3306/smbms?useUnicode=true&characterEncoding=utf-8&useSSL=false
username=root
password=123456

    2、编写数据库的公共类

    三种拿到db.properties文件的方法

    InputStream is = BaseDao.class.getClassLoader().getResourceAsStream("db.properties");
InputStream is = ClassLoader.getSystemResourceAsStream("db.properties");
InputStream is = BaseDao.class.getResourceAsStream("/db.properties");
FileReader is = new FileReader("src/main/resources/db.properties");

properties.load(is);

    package dao;

import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;

/**
 * 操作数据库的基类--静态类
 * @author Administrator
 *
 */
public class BaseDao {
	
	static{//静态代码块,在类加载的时候执行
		init();
	}
	
	private static String driver;
	private static String url;
	private static String user;
	private static String password;
	
	//初始化连接参数,从配置文件里获得
	public static void init(){
		Properties params=new Properties();
		String configFile = "database.properties";
		InputStream is=BaseDao.class.getClassLoader().getResourceAsStream(configFile);
		try {
			params.load(is);
		} catch (IOException e) {
			e.printStackTrace();
		}
		driver=params.getProperty("driver");
		url=params.getProperty("url");
		user=params.getProperty("user");
		password=params.getProperty("password");

	}   
	
	
	/**
	 * 获取数据库连接
	 * @return
	 */
	public static Connection getConnection(){
		Connection connection = null;
		try {
			Class.forName(driver);
			connection = DriverManager.getConnection(url, user, password);
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		return connection;
	}
	/**
	 * 查询操作
	 * @param connection
	 * @param pstm
	 * @param rs
	 * @param sql
	 * @param params
	 * @return
	 */
	public static ResultSet execute(Connection connection,PreparedStatement pstm,ResultSet rs,
			String sql,Object[] params) throws Exception{
		pstm = connection.prepareStatement(sql);
		for(int i = 0; i < params.length; i++){
			pstm.setObject(i+1, params[i]);
		}
		rs = pstm.executeQuery();
		return rs;
	}
	/**
	 * 更新操作
	 * @param connection
	 * @param pstm
	 * @param sql
	 * @param params
	 * @return
	 * @throws Exception
	 */
	public static int execute(Connection connection,PreparedStatement pstm,
			String sql,Object[] params) throws Exception{
		int updateRows = 0;
		pstm = connection.prepareStatement(sql);
		for(int i = 0; i < params.length; i++){
			pstm.setObject(i+1, params[i]);
		}
		updateRows = pstm.executeUpdate();
		return updateRows;
	}
	
	/**
	 * 释放资源
	 * @param connection
	 * @param pstm
	 * @param rs
	 * @return
	 */
	public static boolean closeResource(Connection connection,PreparedStatement pstm,ResultSet rs){
		boolean flag = true;
		if(rs != null){
			try {
				rs.close();
				rs = null;//GC回收
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
				flag = false;
			}
		}
		if(pstm != null){
			try {
				pstm.close();
				pstm = null;//GC回收
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
				flag = false;
			}
		}
		if(connection != null){
			try {
				connection.close();
				connection = null;//GC回收
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
				flag = false;
			}
		}
		
		return flag;
	}

}

    3、编写字符编码过滤器

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

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        servletRequest.setCharacterEncoding("utf-8");
        servletResponse.setCharacterEncoding("utf-8");
        servletResponse.setContentType("text/html;charset=UTF-8");

        filterChain.doFilter(servletRequest,servletResponse);
    }

    @Override
    public void destroy() {

    }
}

    然后在web.xml中注册

    <!--字符编码过滤器-->
<filter>
    <filter-name>CharacterEncodingFilter</filter-name>
    <filter-class>com.yingxu.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

    smbms项目静态资源+数据库下载 密码:smbms

    放在webapp目录下

    在这里插入图片描述

登录功能实现

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  1. 编写前端页面

  2. 设置首页

    1.设置欢迎首页

    <!--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

    在dao中建立一个user包，在包中建一个UserDao接口，在接口中写

    public interface UserDao {
    public User getLoginUser(Connection connection,String userCode) throws SQLException;
}

  4. 编写dao层接口的实现类

    编写UserDao接口的实现类UserDaoImpl

    public class UserDaoImpl implements UserDao{
    //持久层只做查询数据库的内容
    @Override
    public User getLoginUser(Connection connection, String userCode) throws SQLException {
        PreparedStatement preparedStatement=null;
        ResultSet resultSet=null;
        User user=null;
        //判断是否连接成功
        if (connection!=null){
            String sql="select * from smbms_user where userCode=?";
            Object[] params={userCode};
            ResultSet execute = BaseDao.execute(connection, preparedStatement, resultSet, sql, params);
            if (execute.next()){
                user = new User();
                user.setId(execute.getInt("id"));
                user.setUserCode(execute.getString("userCode"));
                user.setUserName(execute.getString("userName"));
                user.setUserPassword(execute.getString("userPassword"));
                user.setGender(execute.getInt("gender"));
                user.setBirthday(execute.getDate("birthday"));
                user.setPhone(execute.getString("phone"));
                user.setAddress(execute.getString("address"));
                user.setUserRole(execute.getInt("userRole"));
                user.setCreatedBy(execute.getInt("createdBy"));
                user.setCreationDate(execute.getTimestamp("creationDate"));
                user.setModifyBy(execute.getInt("modifyBy"));
                user.setModifyDate(execute.getTimestamp("modifyDate"));
            }
            BaseDao.closeResource(null,preparedStatement,resultSet);
        }
        return user;
    }
}

  5. 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 userPassword);
}

  6. 业务层接口的实现类

    在service的user包中建立UserServiceImpl类

    public class UserServiceImpl implements UserService{
    //业务层都会调用dao层.所以我们要引入Dao层（重点）
    //只处理对应业务

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

    @Override
    public User login(String userCode, String userPassword) {
        Connection connection = null;
        //通过业务层调用对应的具体数据库操作
        User user = null;
        try {
            connection = BaseDao.getConnection();
            user = userDao.getLoginUser(connection, userCode);
        } catch (Exception e) {
            e.printStackTrace();
        }finally{
            BaseDao.closeResource(connection, null, null);
        }
        return user;
    }
//    @Test
//    public void test(){
//        UserServiceImpl userService = new UserServiceImpl();
//        User login  = userService.login("test", "111");
//        System.out.println(login.getUserPassword());
//    }
}

  7. 编写util

    在util包中建立Constants类

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

  8. 编写Servlet

    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 && userPassword.equals(user.getUserPassword())){ //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);
            //跳转到主页重定向
            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);
    }
}

  9. 注册Servlet

    <!--注册登录页面的Servlet-->
<servlet>
    <servlet-name>LoginServlet</servlet-name>
    <servlet-class>com.yingxu.servlet.user.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>LoginServlet</servlet-name>
    <url-pattern>/login.do</url-pattern>
</servlet-mapping>

  10. 测试访问,保证以上功能可以成功

登录功能优化

注销功能
思路：移除session，返回登录页面,servlet.user下创建LogoutServlet类

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

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

在web.xml中注册注销servlet

<!--移除session-->
<servlet>
    <servlet-name>LogoutServlet</servlet-name>
    <servlet-class>com.yingxu.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

在filter下创建SysFilter类

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

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) servletRequest;
        HttpServletResponse resp = (HttpServletResponse) servletResponse;

        User user = (User) req.getSession().getAttribute(Constants.USER_SESSION);
        if (user==null){
            resp.sendRedirect(req.getContextPath()+"/error.jsp");
        }else {
            filterChain.doFilter(servletRequest,servletResponse);
        }
    }

    @Override
    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.yingxu.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

自顶向下设计，自底向上实现

先写基本逻辑，前端在测试后端的路上完善的

  • 为了实这个功能需要自底向上逐一实现功能，修改密码需要更新数据库的相关行，所以这就需要dao层去进行增删改查操作数据
  • dao层的需要的当前的一些信息，比如用户名，当前的密码，要修改的密码，所以这些就要dao层去从Service层获取这些参数
  • service需要获取从Servlet层传过来的数据进行相应的处理，验证，核算，然后将最终的信息传递给dao层
  • 而servlet直接与前端接触，返回当前页面上传递而来的用户输入触发的参数，转发到不同的页面，交给不同的service来处理这些请求意味着先从dao层开始写，分模块，先写接口，再写接口的实现类，依次写service和servlet，最后注册这个servlet，最后测试并完善前端页面

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  1. 编写dao层用户修改密码的接口UserDao

    在dao.user.UserDao的接口下增加updatepwd

    //修改当前用户密码
//增删改都会影响数据库的变化，所以是返回int类型，说明有几行受到了影响
public int updatePwd(Connection connection,int id,String userPassword) throws SQLException;

  2. 编写dao层用户修改密码的接口实现类

    UserDaoImpl下增加

    //修改当前用户密码
//增删改都会影响数据库的变化，所以是返回int类型，说明有几行受到了影响
@Override
public int updatePwd(Connection connection, int id, String userPassword) throws SQLException {
    int execute=0;
    PreparedStatement preparedStatement=null;
    if (connection!=null){
        String sql="update smbms_user set userPassword=? where id=?";
        Object[] params={userPassword,id};
        execute = BaseDao.execute(connection, preparedStatement, sql, params);
    }
    BaseDao.closeResource(null,preparedStatement,null);
    return execute;
}

  3. 编写业务层Service的用户修改密码的接口

    UserService下增加

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

  4. 编写业务层Service的用户修改密码的接口实现类

    UserServiceImpl下增加

    //根据用户id修改密码
//通过返回的参数flag判断是否修改成功
@Override
public boolean updatePwd(int id, String password) {
    Connection connection=null;
    boolean flag=false;

    try {
        connection = BaseDao.getConnection();
        int updatePwd = userDao.updatePwd(connection, id, password);
        if (updatePwd>0){
            flag=true;
        }
    } catch (SQLException e) {
        e.printStackTrace();
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return flag;
}

  5. 编写修改密码的Servlet类

    servlet.user 下新增UserServlet类

    public class UserServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //实现复用~~~~~~
        //实现Servlet复用，实现复用需要提取出方法，然后在doGet函数中调用即可
        // 想添加新的增删改查，直接用if(method.equals("savepwd") && method != null);
        String method = req.getParameter("method");
        if (method.equals("savepwd") && method!=null){
            updatePwd(req,resp);
        }
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    //在doGet外写复用方法
    public void updatePwd(HttpServletRequest req, HttpServletResponse resp){
        //从session中获得用户id,这里的attribute包括了用户的所用信息
        Object attribute = req.getSession().getAttribute(Constants.USER_SESSION);
        //获得新密码
        String newpassword = req.getParameter("newpassword");
        boolean flag=false;
        //判断是否有这个用户是否存在，以及新密码不为空
        if (attribute!=null && !StringUtils.isNullOrEmpty(newpassword)){
            UserService userService = new UserServiceImpl();
            flag = userService.updatePwd(((User) attribute).getId(), newpassword);
            if (flag){
                req.setAttribute("message","修改密码成功，请退出后重新登录");
                // 密码修改成功,移除session(移除后不能再次修改密码,建议不移除)
                req.getSession().removeAttribute(Constants.USER_SESSION);
            }else {
                // 密码修改失败
                req.setAttribute("message","密码修改失败请重新输入");
            }
        }else {
            // 密码修改有问题
            req.setAttribute("message","新密码设置错误请重新输入");
        }
        try {
            req.getRequestDispatcher("/jsp/pwdmodify.jsp").forward(req,resp);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

  6. 在web.xml中注册这个servlet

    <!--注册UserServlet页面-->
<servlet>
    <servlet-name>UserServlet</servlet-name>
    <servlet-class>com.yingxu.servlet.user.UserServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>UserServlet</servlet-name>
    <url-pattern>/jsp/user.do</url-pattern>
</servlet-mapping>

  7. 如果旧密码输入框一直报错（打开pwdmodify.js 注释下面这段）

    在这里插入图片描述

  8. 测试

优化密码修改使用Ajax

阿里巴巴的fastjson.jar包

<!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.83</version>
</dependency>

在这里插入图片描述

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设置session过期时间

<!--默认session过期时间:真实业务需求，1天后自动注销-->
<session-config>
    <session-timeout>1440</session-timeout>
</session-config>

编写验证旧密码的servlet类，还是servlet方法复用

public class UserServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //实现复用~~~~~~
        //实现Servlet复用，实现复用需要提取出方法，然后在doGet函数中调用即可
        // 想添加新的增删改查，直接用if(method.equals("savepwd") && method != null);
        String method = req.getParameter("method");
        if (method.equals("savepwd") && method!=null){
            this.updatePwd(req,resp);
        }else if (method!=null && method.equals("pwdmodify")){
            this.modifyPwd(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中获得用户id,这里的attribute包括了用户的所用信息
        Object attribute = req.getSession().getAttribute(Constants.USER_SESSION);
        //获得新密码
        String newpassword = req.getParameter("newpassword");
        boolean flag=false;
        //判断是否有这个用户是否存在，以及新密码不为空
        if (attribute!=null && !StringUtils.isNullOrEmpty(newpassword)){
            UserService userService = new UserServiceImpl();
            flag = userService.updatePwd(((User) attribute).getId(), newpassword);
            if (flag){
                req.setAttribute("message","修改密码成功，请退出后重新登录");
                // 密码修改成功,移除session(移除后不能再次修改密码,建议不移除)
                req.getSession().removeAttribute(Constants.USER_SESSION);
            }else {
                // 密码修改失败
                req.setAttribute("message","密码修改失败请重新输入");
            }
        }else {
            // 密码修改有问题
            req.setAttribute("message","新密码设置错误请重新输入");
        }
        try {
            req.getRequestDispatcher("/jsp/pwdmodify.jsp").forward(req,resp);
        } catch (ServletException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    //数证旧密码,session中有用户的密码
    public void modifyPwd(HttpServletRequest req, HttpServletResponse resp){
        //从session中获得用户的旧密码,这里的attribute包括了用户的所用信息
        Object attribute = req.getSession().getAttribute(Constants.USER_SESSION);
        //从前端输入的页面中获得输入的旧密码
        String oldpassword = req.getParameter("oldpassword");
        //万能的Map:结果集
        Map<String, String> resultMap = new HashMap<String, String>();
        if (attribute==null){//取到的session为空，意味着session过期了
            resultMap.put("result","sessionerror");
        }else if (StringUtils.isNullOrEmpty(oldpassword)){//如果输入的旧密码为空
            resultMap.put("result","error");
        }else {//session不为空，输入的旧密码也不为空，则取出当前旧密码与之比较
            String userPassword = ((User) attribute).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();
            /*
             * resultMap = ["result","sessionerror","result",error]
             * json格式={key:value}
             */
            writer.write(JSONArray.toJSONString(resultMap));
            writer.flush();
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

用户管理模块实现

在这里插入图片描述

  1. 导入分页的util工具类-PageSupport

    public class PageSupport {
   //当前页码-来自于用户输入
   private int currentPageNo = 1;
   
   //总数量（表）
   private int totalCount = 0;
   
   //页面容量
   private int pageSize = 0;
   
   //总页数-totalCount/pageSize（+1）
   private int totalPageCount = 1;

   public int getCurrentPageNo() {
      return currentPageNo;
   }

   public void setCurrentPageNo(int currentPageNo) {
      if(currentPageNo > 0){
         this.currentPageNo = currentPageNo;
      }
   }

   public int getTotalCount() {
      return totalCount;
   }

   public void setTotalCount(int totalCount) {
      if(totalCount > 0){
         this.totalCount = totalCount;
         //设置总页数
         this.setTotalPageCountByRs();
      }
   }
   public int getPageSize() {
      return pageSize;
   }

   public void setPageSize(int pageSize) {
      if(pageSize > 0){
         this.pageSize = pageSize;
      }
   }

   public int getTotalPageCount() {
      return totalPageCount;
   }

   public void setTotalPageCount(int totalPageCount) {
      this.totalPageCount = totalPageCount;
   }
   
   public void setTotalPageCountByRs(){
      if(this.totalCount % this.pageSize == 0){
         this.totalPageCount = this.totalCount / this.pageSize;
      }else if(this.totalCount % this.pageSize > 0){
         this.totalPageCount = this.totalCount / this.pageSize + 1;
      }else{
         this.totalPageCount = 0;
      }
   }
   
}

  2. 用户列表页面导入-userlist.jsp

1、获取用户数量

  1. 编写Dao层的接口UserDao

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

  2. 编写Dao层的实现类UserDaoImpl

    //根据用户名或者角色查询用户总数
@Override
public int getUserCount(Connection connection, String username, int userRole) throws SQLException, Exception {
    PreparedStatement preparedStatement=null;
    ResultSet resultSet=null;
    //不能使用Integer去包装，Integer可以为null，这里返回的的结果是始终是int类型
    int count=0;
    if (connection!=null){
        //因为根据用户角色或用户名的条件查询，需要使用StringBuffer去拼接字符串
        StringBuffer sql = new StringBuffer();
        sql.append("select count(1) as count from smbms_user u,smbms_role r where u.userRole=r.id");
        //使用list集合去封装参数
        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);
        }
        Object[] params = list.toArray();
        resultSet = BaseDao.execute(connection, preparedStatement, resultSet, sql.toString(), params);
        if (resultSet.next()){
            count = resultSet.getInt("count");//这里count是sql里的as count
        }
        BaseDao.closeResource(null,preparedStatement,resultSet);
    }
    return count;
}

  3. 编写service层的接口UserService

    //根据用户名或用户角色查询用户总数
public int getUserCount(String username,int userRole) throws SQLException;

  4. 编写service层的实现类UserServiceImpl

    //根据用户名或用户角色查询用户总数
@Override
public int getUserCount(String username, int userRole) throws SQLException {
    Connection connection=null;
    int count=0;
    try {
        connection = BaseDao.getConnection();
        count = userDao.getUserCount(connection, username, userRole);
    } catch (Exception e) {
        e.printStackTrace();
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return count;
}

2、获取用户列表

  1. UserDao

    //查询用户列表
//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 SQLException {
    PreparedStatement pstm = null;
    ResultSet rs = null;
    List<User> userList = new ArrayList<User>();
    if(connection != null){
        StringBuffer sql = new StringBuffer();
        //当查询语句有order by时u.*,r.roleName 要加上前缀u.,r.
        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，分页显示 limit startIndex，pageSize；总数
        //当前页  (当前页-1)*页面大小
        //0,5  1,0     01234
        //5,5  5,0     56789
        //10,5 10,0 10~
        sql.append(" order by u.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. UserServiceImpl

    //根据条件查询用户列表
@Override
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

为了我们的职责分明，需要将角色列表另一起一个包，便于代码的维护

分别在dao，service下创捷role文件夹

  1. RoleDao

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

  2. RoleDaoIpml

    public class RoleDaoImpl implements RoleDao{
    //获取角色列表
    @Override
    public List<Role> getRoleList(Connection connection) throws SQLException {
        PreparedStatement preparedStatement=null;
        ResultSet resultSet=null;
        Role role=null;
        ArrayList<Role> roles = new ArrayList<>();
        if (connection!=null){
            String sql="select * from smbms_role";
            Object[] params={};
            resultSet = BaseDao.execute(connection, preparedStatement, resultSet, sql, params);
            while (resultSet.next()){
                role = new Role();
                role.setId(resultSet.getInt("id"));
                role.setRoleCode(resultSet.getString("roleCode"));
                role.setRoleName(resultSet.getString("roleName"));
                roles.add(role);
            }
            BaseDao.closeResource(null,preparedStatement,resultSet);
        }
        return roles;
    }
}

  3. RoleService

    public interface RoleService {
    //得到用户角色表
    public List<Role> getRoleList();
}

  4. RoleServiceIpml

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

    //得到用户角色表
    @Override
    public List<Role> getRoleList() {
        Connection connection=null;
        List<Role> list=null;
        try {
            connection = BaseDao.getConnection();
            list = roleDao.getRoleList(connection);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            BaseDao.closeResource(connection,null,null);
        }
        return list;
    }

//    @Test
//    public void test(){
//        RoleServiceImpl roleService = new RoleServiceImpl();
//        List<Role> roleList = roleService.getRoleList();
//        for (Role role : roleList) {
//            System.out.println(role.getRoleName());
//        }
//    }
}

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

UserServlet类doGet方法里：

else if (method.equals("query") && method!=null){
    //用户管理模块页面查询
    this.query(req,resp);
}

//用户管理模块页面查询(重点、难点)
public void query(HttpServletRequest req, HttpServletResponse resp){
    //接收前端传来的参数

    //用户名
    String queryUserName = req.getParameter("queryname");
    //用户角色
    String temp = req.getParameter("queryUserRole");//从前端传回来的用户角色码不知是否为空或者是有效角色码，所以暂存起来
    //当前页
    String pageIndex = req.getParameter("pageIndex");
    int queryUserRole=0;//用户角色=0：--请选择--，用户角色=1：系统管理员，...

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

    //第一此请求肯定是走第一页，页面大小固定的
    //设置页面容量
    int pageSize = 5;//把它设置在配置文件里,后面方便修改
    //当前页码
    int currentPageNo = 1;

    if(queryUserName == null){
        queryUserName = "";
    }
    if(temp != null && !temp.equals("")){
        queryUserRole = Integer.parseInt(temp);
    }
    if(pageIndex != null) {
        currentPageNo = Integer.parseInt(pageIndex);
    }
    //获取用户总数（分页    上一页：下一页的情况）
    //总数量（表）
    int totalCount = 0;
    try {
        totalCount = userService.getUserCount(queryUserName,queryUserRole);
    } catch (SQLException e) {
        e.printStackTrace();
    }

    //总页数支持
    PageSupport pageSupport = new PageSupport();
    pageSupport.setCurrentPageNo(currentPageNo);
    pageSupport.setPageSize(pageSize);
    pageSupport.setTotalCount(totalCount);

    //(totalCount+pageSize-1/pageSize)取整
    int totalPageCount =pageSupport.getTotalPageCount();//总共有几页

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

    System.out.println("queryUserName"+"="+queryUserName);
    System.out.println("queryUserRole"+"="+queryUserRole);
    System.out.println("currentPageNo"+"="+currentPageNo);
    System.out.println("pageSize"+"="+pageSize);

    userList = userService.getUserList(queryUserName, queryUserRole, currentPageNo, pageSize);
    System.out.println("userList"+userList);

    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();
    }

}

小黄鸭调试法自查

思路：

在这里插入图片描述

5、用户管理模块的增删改查

UserDao

//增加用户信息
public int addUser(Connection connection,User user) throws SQLException;

//通过用户id删除用户信息
public int deleteUserById(Connection connection, Integer delId) throws SQLException;

//通过userId查看当前用户信息
public User getUserById(Connection connection, String id)throws Exception;

//修改用户信息
public int updateUser(Connection connection, User user)throws Exception;

UserDaoImpl

//增加用户信息
@Override
public int addUser(Connection connection, User user) throws SQLException {
    PreparedStatement preparedStatement=null;
    int execute=0;
    if (connection!=null){
        String sql="insert into smbms_user(userCode,userName,userPassword,gender,birthday,phone,address,userRole,createdBy,creationDate) values(?,?,?,?,?,?,?,?,?,?)";
        Object[] params={user.getUserCode(),user.getUserName(),user.getUserPassword(),user.getGender(),user.getBirthday(),user.getPhone(),user.getAddress(),user.getUserRole(),user.getCreatedBy(),user.getCreationDate()};
        execute = BaseDao.execute(connection, preparedStatement, sql, params);
    }
    BaseDao.closeResource(null,preparedStatement,null);
    return execute;
}

//通过用户id删除用户信息
@Override
public int deleteUserById(Connection connection, Integer delId) throws SQLException {
    PreparedStatement preparedStatement=null;
    int execute=0;
    if (connection!=null){
        String sql="delete from smbms_user where id=?";
        Object[] params={delId};
        execute = BaseDao.execute(connection, preparedStatement, sql, params);
    }
    BaseDao.closeResource(null,preparedStatement,null);
    return execute;
}

//修改用户信息
@Override
public int updateUser(Connection connection, User user) throws Exception {
    PreparedStatement preparedStatement=null;
    int execute=0;
    if (connection!=null){
        String sql="update smbms_user set userName=?,gender=?,birthday=?,phone=?,address=?,userRole=?,modifyBy=?,modifyDate=? where id=?";
        Object[] params={user.getUserName(),user.getGender(),user.getBirthday(),user.getPhone(),user.getAddress(),user.getUserRole(),user.getModifyBy(),user.getModifyDate(),user.getId()};
        execute = BaseDao.execute(connection, preparedStatement, sql, params);
    }
    BaseDao.closeResource(null,preparedStatement,null);
    return execute;
}

//通过userId查看当前用户信息
@Override
public User getUserById(Connection connection, String id) throws Exception {
    PreparedStatement preparedStatement=null;
    ResultSet resultSet=null;
    User user=null;
    if (connection!=null){
        String sql="select u.*,r.roleName as userRoleName from smbms_user u,smbms_role r where u.id=? and u.userRole = r.id";
        Object[] params={id};
        resultSet = BaseDao.execute(connection, preparedStatement, resultSet, sql, params);
        while (resultSet.next()){
            user = new User();
            user.setId(resultSet.getInt("id"));
            user.setUserCode(resultSet.getString("userCode"));
            user.setUserName(resultSet.getString("userName"));
            user.setUserPassword(resultSet.getString("userPassword"));
            user.setGender(resultSet.getInt("gender"));
            user.setBirthday(resultSet.getDate("birthday"));
            user.setPhone(resultSet.getString("phone"));
            user.setAddress(resultSet.getString("address"));
            user.setUserRole(resultSet.getInt("userRole"));
            user.setCreatedBy(resultSet.getInt("createdBy"));
            user.setCreationDate(resultSet.getTimestamp("creationDate"));
            user.setModifyBy(resultSet.getInt("modifyBy"));
            user.setModifyDate(resultSet.getTimestamp("modifyDate"));
            user.setUserRoleName(resultSet.getString("userRoleName"));
        }
        BaseDao.closeResource(null,preparedStatement,resultSet);
    }
    return user;
}

UserService

//查询用户编码
//查询用户是否存在，存在就不能增加用户，不存在就增加用户
public User selectUserCodeExist(String userCode);

//增加用户
public Boolean add(User user);

//根据用户id删除用户
public boolean deleteUserById(Integer delId);

//根据用户id得到当前用户
public User getUserById(String id);

//修改用户信息
public Boolean updateUser(User user);

UserServiceImpl

//查询用户编码
//查询用户是否存在，存在就不能增加用户，不存在就增加用户
@Override
public User selectUserCodeExist(String userCode) {
    Connection connection = null;
    User users=null;
    try {
        connection = BaseDao.getConnection();
        users = userDao.getLoginUser(connection, userCode);
    } catch (SQLException e) {
        e.printStackTrace();
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return users;
}

//增加用户
@Override
public Boolean add(User user) {
    Connection connection = null;
    int add=0;
    boolean flag=false;
    try {
        connection = BaseDao.getConnection();
        connection.setAutoCommit(false);//开启JDBC事务管理
        add = userDao.addUser(connection, user);
        connection.commit();
        if (add>0){
            flag=true;
            System.out.println("add success");
        }else {
            System.out.println("add failed");
        }
    } catch (SQLException e) {
        e.printStackTrace();
        try {
            System.out.println("rollback==================");
            connection.rollback();//失败就回滚
        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return flag;
}

//根据用户id删除用户
@Override
public boolean deleteUserById(Integer delId) {
    Connection connection=null;
    int deleteUserById=0;
    boolean flag=false;
    try {
        connection = BaseDao.getConnection();
        deleteUserById = userDao.deleteUserById(connection, delId);
        if (deleteUserById>0){
            flag=true;
        }
    } catch (SQLException e) {
        e.printStackTrace();
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return flag;
}

//根据用户id得到当前用户
@Override
public User getUserById(String id) {
    User user = new User();
    Connection connection=null;
    try {
        connection=BaseDao.getConnection();
        user = userDao.getUserById(connection,id);
    } catch (Exception e) {
        e.printStackTrace();
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return  user;
}

//修改用户信息
@Override
public Boolean updateUser(User user) {
    Connection connection = null;
    int updateUser=0;
    boolean flag=false;
    try {
        connection = BaseDao.getConnection();
        connection.setAutoCommit(false);//开启JDBC事务管理
        updateUser = userDao.updateUser(connection, user);
        connection.commit();
        if (updateUser>0){
            flag=true;
            System.out.println("修改成功");
        }else {
            System.out.println("修改失败");
        }
    } catch (Exception e) {
        e.printStackTrace();
        try {
            System.out.println("rollback==================");
            connection.rollback();//失败就回滚
        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    }finally {
        BaseDao.closeResource(connection,null,null);
    }
    return flag;
}

增删改查UserServlet

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    //实现复用~~~~~~
    //实现Servlet复用，实现复用需要提取出方法，然后在doGet函数中调用即可
    // 想添加新的增删改查，直接用if(method.equals("savepwd") && method != null);
    String method = req.getParameter("method");
    if (method.equals("savepwd") && method!=null){
        //修改密码
        this.updatePwd(req,resp);
    }else if (method.equals("pwdmodify") && method!=null){
        //数证旧密码
        this.pwdModify(req,resp);
    }else if (method.equals("query") && method!=null){
        //用户管理模块页面查询
        this.query(req,resp);
    }else if (method.equals("getrolelist") && method!=null){
        //查询用户角色表
        this.getRoleList(req,resp);
    } else if (method.equals("ucexist") && method!=null){
        //判断用户编码是否存在(存在就不能增加用户，不存在就增加用户)
        this.isUserExist(req,resp);
    }else if (method.equals("add") && method!=null){
        //增加用户
        this.add(req,resp);
    }else if(method.equals("deluser") && method!=null){
        //删除用户
        this.delUser(req, resp);
    }else if(method.equals("view") && method!=null){
        //通过用户id得到用户
        this.getUserById(req, resp,"/jsp/userview.jsp");
    }else if(method.equals("modify") && method!=null){
        //通过用户id得到用户
        this.getUserById(req, resp,"/jsp/usermodify.jsp");
    } else if(method.equals("modifyexe") && method!=null){
        //修改用户信息
        this.updateUser(req, resp);
    }
}



//查询用户角色表
public void getRoleList(HttpServletRequest req, HttpServletResponse resp){
    List<Role> roleList = null;
    RoleService roleService = new RoleServiceImpl();
    roleList = roleService.getRoleList();
    try {
        //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();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

//判断用户编码是否存在(存在就不能增加用户，不存在就增加用户)
public void isUserExist(HttpServletRequest req, HttpServletResponse resp) {
    //获取前端参数
    String userCode = req.getParameter("userCode");
    //使用Map封装数据
    HashMap<String, String> resultMap = new HashMap<String, String>();
    if(StringUtils.isNullOrEmpty(userCode)){
        //userCode == null || userCode.equals("")
        //如果输入的这个编码为空或者不存在，说明可用
        resultMap.put("userCode", "exist");
    }else{//如果输入的编码不为空，则需要去找一下是否存在这个用户
        UserService userService = new UserServiceImpl();
        User user = userService.selectUserCodeExist(userCode);
        if(user!=null){
            resultMap.put("userCode","exist");
        }else{
            resultMap.put("userCode", "notexist");
        }
    }
    try {
        resp.setContentType("application/json");
        PrintWriter writer = resp.getWriter();
        /*
         * resultMap = ["result","sessionerror","result",error]
         * json格式={key:value}
         */
        writer.write(JSONArray.toJSONString(resultMap));
        writer.flush();
        writer.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

}

//增加用户
public void add(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException {
    System.out.println("当前正在执行增加用户操作");
    //从前端得到页面的请求的参数即用户输入的值
    String userCode = req.getParameter("userCode");
    String userName = req.getParameter("userName");
    String userPassword = req.getParameter("userPassword");
    //String ruserPassword = req.getParameter("ruserPassword");
    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");
    //把这些值塞进一个用户属性中
    User user = new User();
    user.setUserCode(userCode);
    user.setUserName(userName);
    user.setUserPassword(userPassword);
    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));
    Object o = req.getSession().getAttribute(Constants.USER_SESSION);
    //查找当前正在登陆的用户的id
    if (o != null) {
        user.setCreatedBy(((User) o).getId());
    }
    user.setCreationDate(new Date());

    UserServiceImpl userService = new UserServiceImpl();
    Boolean flag = userService.add(user);
    //如果添加成功，则页面转发，否则重新刷新，再次跳转到当前页面
    if(flag){
        resp.sendRedirect(req.getContextPath()+"/jsp/user.do?method=query");
    }else{
        req.getRequestDispatcher("/jsp/useradd.jsp").forward(req,resp);
    }
}

//删除用户，需要当前的Id，来找到这个用户然后删除
public void delUser(HttpServletRequest req, HttpServletResponse resp){
    String id = req.getParameter("uid");
    Integer delId = 0;
    try{
        delId = Integer.parseInt(id);
    }catch (Exception e) {
        delId = 0;
    }
    //需要判断是否能删除成功
    HashMap<String, String> resultMap = new HashMap<String, String>();
    if(delId <= 0){
        resultMap.put("delResult", "notexist");
    }else{
        UserService userService = new UserServiceImpl();
        if(userService.deleteUserById(delId)){
            resultMap.put("delResult", "true");
        }else{
            resultMap.put("delResult", "false");
        }
    }

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

//通过id得到用户信息
private void getUserById(HttpServletRequest req, HttpServletResponse resp,String url) throws ServletException, IOException {
    String id = req.getParameter("uid");
    if(!StringUtils.isNullOrEmpty(id)){
        //调用后台方法得到user对象
        UserService userService = new UserServiceImpl();
        User user = userService.getUserById(id);
        req.setAttribute("user", user);
        req.getRequestDispatcher(url).forward(req, resp);
    }
}

//修改用户信息
private void updateUser(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException {
    //需要拿到前端传递进来的参数
    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");

    //创建一个user对象接收这些参数
    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.setModifyBy(((User)req.getSession().getAttribute(Constants.USER_SESSION)).getId());
    user.setModifyDate(new Date());

    //调用service层
    UserServiceImpl userService = new UserServiceImpl();
    Boolean flag = userService.updateUser(user);

    //判断是否修改成功来决定跳转到哪个页面
    if(flag){
        resp.sendRedirect(req.getContextPath()+"/jsp/user.do?method=query");
    }else{
        req.getRequestDispatcher("/jsp/usermodify.jsp").forward(req, resp);
    }

}

SMBMS项目其他模块

SMBMS项目其他模块参考

标签：JavaWeb,int,req,超市,connection,SMBMS,user,null,public
From： https://www.cnblogs.com/yingxu/p/16748557.html

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