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SMBMS超市订单管理系统

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MVC三层架构(代码整体以此分层编写)

  • 整体的流程与代码编写思路

建议是从后往前写,便于调试与debug,先编写Dao层,主要负责与数据库交互,编写sql语句等。然后编写Servicce层,主要负责调用Dao层,再编写Servlet层,其也是主要调用Service和前端的一些数据交互,比如resquet和response等。

基本架构

项目搭建准备工作

1- 4

5 创建项目包结构

6-7

package com.tong.dao;

import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
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 = "db.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);
		//向sql中的占位符加载参数Object[] params
		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,如果rs.close();没关上,让其等于null,使垃圾回收器自动回收。
			} 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;
	}

}

8 导致静态资源

  • 放在webapp目录下,因为是网站资源

登录功能实现

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="${pageContext.request.contextPath }/css/style.css" />
    <script type="text/javascript">
	/* if(top.location!=self.location){
	      top.location=self.location;
	 } */
    </script>
</head>
<body class="login_bg">
    <section class="loginBox">
        <header class="loginHeader">
            <h1>超市订单管理系统</h1>
        </header>
        <section class="loginCont">
	        <form class="loginForm" action="${pageContext.request.contextPath }/login.do"  name="actionForm" id="actionForm"  method="post" >
				<div class="info">${
   error }</div>
				<div class="inputbox">
                    <label for="userCode">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 for="userPassword">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.设置首页

<!--设置欢迎界面-->
    <welcome-file-list>
        <welcome-file>login.jsp</welcome-file>
    </welcome-file-list>

3.编写Dao层用户登录的接口

  • Dao层(数据持久层)负责操作数据库,业务(比如用户登录,比对账号密码)有业务层负责。
public User getLoginUser(Connection connection, String userCode)throws Exception;

4.编写Dao接口实现类

public User getLoginUser(Connection connection, String userCode) throws Exception {
   
		// TODO Auto-generated method stub
		PreparedStatement pstm = null;
		ResultSet rs = null;
		User user = null;
		if(null != connection){
   
			String sql = "select * from smbms_user where userCode=?";
			Object[] params = {
   userCode};
			rs = BaseDao.execute(connection, pstm, rs, sql, params);
			if(rs.next()){
   
				user = new User();
				user.setId(rs.getInt("id"));
				user.setUserCode(rs.getString("userCode"));
				user.setUserName(rs.getString("userName"));
				user.setUserPassword(rs.getString("userPassword"));
				user.setGender(rs.getInt("gender"));
				user.setBirthday(rs.getDate("birthday"));
				user.setPhone(rs.getString("phone"));
				user.setAddress(rs.getString("address"));
				user.setUserRole(rs.getInt("userRole"));
				user.setCreatedBy(rs.getInt("createdBy"));
				user.setCreationDate(rs.getTimestamp("creationDate"));
				user.setModifyBy(rs.getInt("modifyBy"));
				user.setModifyDate(rs.getTimestamp("modifyDate"));
			}
			//connection设成null不让其关闭,是因为后面业务层还需要数据库连接。
			BaseDao.closeResource(null, pstm, rs);
		}
		return user;
	}

5.业务层接口

  • 业务层都会调用Dao层,来获取业务所需的数据。
public interface UserService {
   
	 //用户登录
	public User login(String userCode, String userPassword);
}

6.业务层实现类

  • 因为业务层要调用Dao层(来获取数据库的数据),调用Dao层,就需要给它传参数,则connection此时传给Dao层,所以connection对象在业务层创建。
  • 业务层存在事务,失败了会回滚。,所以connection对象在业务层创建。
public class UserServiceImpl implements UserService{
   
	
	private UserDao userDao;
	public UserServiceImpl(){
   
		userDao = new UserDaoImpl();
	}
	public User login(String userCode, String userPassword) {
   
		// TODO Auto-generated method stub
		Connection connection = null;
		User user = null;
		try {
   
			connection = BaseDao.getConnection();
			user = userDao.getLoginUser(connection, userCode);
		} catch (Exception e) {
   
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
   
			BaseDao.closeResource(connection, null, null);
		}
		
		//匹配密码
		if(null != user){
   
			if(!user.getUserPassword().equals(userPassword))
				user = null;
		}
		
		return user;
	}
}

7.编写servlet

  • servlet是控制层,用来调用业务层
  • 控制层的作用:接受用户的请求交给业务层去做,这里用户的请求是登录(输入用户名和密码请求登录),业务层要做的是在数据库中匹配输入的用户名和密码。
public class LoginServlet extends HttpServlet {
   
    //servlet:控制层,接收用户的请求,调用业务层代码。

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
   
        //从前端获取用户名和密码(接收用户的请求)
        String userCode = req.getParameter("userCode");
        String userPassword = req.getParameter("userPassword");

        //接收请求后需处理业务,业务是:和数据库中的数据进行对比,所以需调用业务层
        UserServiceImpl userService = new UserServiceImpl();
        User user = userService.login(userCode, userPassword);//这里已经把登录的人给查出来了

        if(user != null){
   //查有此人,可以登录
            //将用户的信息放入Session中
            req.getSession().setAttribute(Constant.USER_SESSION , user);
            //跳转主页(跳转到另一个页面,地址变了,所以用重定向)
            resp.sendRedirect("jsp/frame.jsp");

        }else{
   //查无此人,无法登录
            //转发会登录页面,顺带提示它,用户名或密码错误。((跳转到本页面,只是在本页面加了些信息(用户名或密码错误),地址没变,所以用请求转发))
            req.setAttribute("error" , "用户名或密码错误");//请求可以携带数据
            req.getRequestDispatcher("login.jsp").forward(req , resp);

        }



    }

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

8.注册servlet

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

整体流程

前端一启动,执行login.jsp(设置成了首页),直接到web.xml中设置的login.do(servlet映射),调用对应的控制器servlet(LoginServlet),servlet中会调用业务(UserServiceImpl),然后业务会调用想用的Dao(UserDaoImpl)来获取数据。

登录功能优化

注销功能:

思路:移除session,返回登录界面;

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

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

注册

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

登陆拦截优化

为什么要登陆拦截优化

  • 正常登陆后,将登录界面的网址复制下来,在注销后的登录界面,黏贴复制的网址,在没填用户名和密码的前提下,进入了系统。所以需要登录拦截
  • 拦截判断的条件是 session中有无user这个属性,因为在用户注销,或还没登录的情况下,session中没有user这个属性,如果没有,说明不是正常登录,进行拦截;只有当正常登录时,会创建session中user这个属性,此时可以正常登录。


    注销后,黏贴网址,依然能登录进来,需进行拦截。

具体步骤

编写一个过滤器,并注册

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(Constant.USER_SESSION);
        if(user == null){
   //session已经被移除,或者用户注销,或还没登录
            response.sendRedirect("error.jsp");
        }else{
   
            chain.doFilter(req , resp);
        }
    }

    public void destroy() {
   

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

密码修改

密码修改,需要和数据库打交道,所以还需要走dao层、service层、servlet层这一条线。

  • Dao层:根据用户ID修改用户密码(update语句);
  • service层:接收传过来的密码和调用Dao获取后台的密码,作对比。
  • servlet层:把框里输入的新旧密码拿到,交给业务层。

1.导入前端素材

2.写项目,建议从下向上写

3.编写Dao层修改当前用户密码接口

  • public interface UserDao
     //修改当前用户密码
	//增删改返回的都是int类型,查找返回对应的实体类;
	public int updatePwd(Connection connection, int id, String pwd)throws Exception;

4.编写Dao接口实现类

  • public class UserDaoImpl implements UserDao
public int updatePwd(Connection connection, int id, String pwd)
			throws Exception {
   
		// TODO Auto-generated method stub
		int flag = 0;
		PreparedStatement pstm = null;
		if(connection != null){
   
			String sql = "update smbms_user set userPassword= ? where id = ?";
			Object[] params = {
   pwd,id};
			flag = BaseDao.execute(connection, pstm, sql, params);
			BaseDao.closeResource(null, pstm, null);
		}
		return flag;
	}

5.业务层接口

  • public interface UserService
	//根据userId修改密码
	public boolean updatePwd(int id, String pwd);

6.业务层接口实现类

  • 因为业务层要调用Dao层(来获取数据库的数据),调用Dao层,就需要给它传参数,则connection此时传给Dao层,所以connection对象在业务层创建。
  • 业务层存在事务,失败了会回滚。,所以connection对象在业务层创建。
  • 因为业务层需要调用Dao层,即,这里调用userDao中的方法,这就涉及userDao的创建,有以下两种方法:
    ①在每个方法方法里new一个:UserDao userDao = new UserDaoImpl();
    ②【推荐】利用私有化 加 构造函数引入Dao:
public class UserServiceImpl implements UserService {
   
	//引入Dao,以后spring会代替这一步
	private UserDao userDao;
	public UserServiceImpl(){
   
		userDao = new UserDaoImpl();
	}
	
	。。。。(各个函数)
}
  • public class UserServiceImpl implements UserService
public boolean updatePwd(int id, String pwd) {
   
		boolean flag = false;//使用标志位,判断密码是否修改成功。
		Connection connection = null;
		try{
   
			connection = BaseDao.getConnection();
			if(userDao.updatePwd(connection,id,pwd) > 0)
				flag = true;
		}catch (Exception e) {
   
			e.printStackTrace();
		}finally{
   
			BaseDao.closeResource(connection, null, null);
		}
		return flag;
	}

7.servlet记得实现复用需要提取出方法

//实现servlet复用
public class UserServlet extends HttpServlet {
   
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
   
        String method = req.getParameter("method");
        if(method.equals("savepwd")){
   
            this.updatePwd(req , resp);
        }
    }

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

    public void updatePwd(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
   
        //从session里拿Uer实体类
        Object o = req.getSession().getAttribute(Constant.USER_SESSION);
        String newPassword = req.getParameter("newPassword");

        boolean flag = false;
        if(o != null && newPassword != null && newPassword.length() != 0){
   //Uer实体类和新密码newPassword都拿到了,开始调用业务层
            UserServiceImpl 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,当前session。因为密码变了,session的内容自然也变了,所以需要移除,又因为密码变了需要重新登录,所以session会重新创建
                req.getSession().removeAttribute(Constant.USER_SESSION);
            }else {
   
                req.setAttribute("message" , "密码修改失败");
            }
        }else{
   
            req.setAttribute("message" , "新密码有问题");
        }

        req.getRequestDispatcher("pwdmodify.jsp").forward(req , resp);

    }
}

优化密码修改使用Ajax

1.阿里巴巴的fastjson

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

2.后台代码修改

  • public class UserServlet extends HttpServlet
public void pwdModify(HttpServletRequest req, HttpServletResponse resp) throws IOException {
   
        //从Session中拿ID
        Object o = req.getSession().getAttribute(Constant.USER_SESSION);
        String oldpassword = req.getParameter("oldpassword");

        //万能的Map : 结果集
        Map<String, String> resultMap = new HashMap<String, String>();

        if(null == o ){
   //session过期、失效
            resultMap.put("result", "sessionerror");
        }else if(StringUtils.isNullOrEmpty(oldpassword)){
   //旧密码输入为空
            resultMap.put("result", "error");
        }else{
   
            String sessionPwd = ((User)o).getUserPassword();
            if(oldpassword.equals(sessionPwd)){
   
                resultMap.put("result", "true");
            }else{
   //旧密码输入不正确
                resultMap.put("result", "false");
            }
        }

        resp.setContentType("application/json");
        PrintWriter outPrintWriter = resp.getWriter();
        outPrintWriter.write(JSONArray.toJSONString(resultMap));
        outPrintWriter.flush();
        outPrintWriter.close();
    }

用户管理实现(查询)


思路

导入静态资源

1.导入分页的工具类

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.导入用户列表页面

  • userlist.jsp
  • rollpage.jsp

1.获取用户数量

1.UerDao接口

//通过条件查询-用户表记录数
public int getUserCount(Connection connection, String userName, int userRole)throws Exception;

2.UerDaoImpl【使用动态SQL】

//根据用户名或用户角色查询用户总数
	public int getUserCount(Connection connection, String userName, int userRole) throws Exception {
   
		// TODO Auto-generated method stub
		PreparedStatement pstm = null;
		ResultSet rs = null;
		int count = 0;
		if(connection != null){
   
			//用StringBuffer是因为userName和userRole可能有也可能没有(也就是sql语句不确定,可变-->动态sql),利用StringBuffer的可变性进行随时添加
			StringBuffer sql = new StringBuffer();
			sql.append("select count(1) as count from smbms_user u,smbms_role r where u.userRole = r.id");
			//用ArrayList也是因为应对userName和userRole有没有的情况,随时添加。
			// 如果直接用object[]={userName,userRole}的话,userName和userRole不一定谁有谁没有,这样在dao层的执行语句中给sql语句的占位符(?)复制时,可能参数对不上,使用ArrayList随时添加可以解决这个问题。
			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);
			}
			//把list转换成数组。
			//经过判断,userName和userRole谁存在谁不存在已经确定,list中保存了存在的参数,此时可以转换成数组Object[] params,供BaseDao.execute()调用。
			Object[] params = list.toArray();
			System.out.println("sql ----> " + sql.toString());
			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.UerService接口

//根据条件查询用户表记录数
public int getUserCount(String queryUserName, int queryUserRole);

4.UeServiceImpl

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

2.获取用户列表

  • public List<User> getUserList(),对这个查询用户列表函数,再走一遍上面的流程(如下)
    UerDao接口、UerDaoImpl、UerService接口、UeServiceImpl

3.获取角色列表


为了结构清晰,将角色相关的代码单独放在一个包中,和pojo类对应,编写对应的dao和service

4.用户显示的servlet【这个servlet较为复杂】

至此服务处理完了,编写最后的servlet,这个servlet程序主要包括以下5部分。

//重点、难点
    private void query(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
   
        //查询用户列表
        //从前端获取数据
        String queryUserName = request.getParameter("queryname");
        String temp = request.getParameter("queryUserRole");
        String pageIndex = request.getParameter("pageIndex");
        int queryUserRole = 0;


        UserService userService = new UserServiceImpl();
        List<User> userList = null;
        //设置页面容量。
        // 第一次走这个请求,一定是第一页,页面大小固定
        int pageSize = Constant.pageSize;
        //当前页码
        int currentPageNo = 1;
        /**
         * http://localhost:8090/SMBMS/userlist.do
         * ----queryUserName --NULL
         * http://localhost:8090/SMBMS/userlist.do?queryname=
         * --queryUserName ---""
         */
        System.out.println("queryUserName servlet--------"+queryUserName);
        System.out.println("queryUserRole servlet--------"+queryUserRole);
        System.out.println("query pageIndex--------- > " + pageIndex);

        //判断这些请求是否要处理
        if(queryUserName == null){
   
            queryUserName = "";
        }
        if(temp != null && !temp.equals("")){
   
            queryUserRole = Integer.parseInt(temp);
        }

        if(pageIndex != null){
   
            try{
   
                currentPageNo = Integer.valueOf(pageIndex);
            }catch(NumberFormatException e){
   
                response.sendRedirect("error.jsp");
            }
        }
        //为了实现分页,需要计算出当前页面和总页面,页面大小...
        //总数量(表)
        int totalCount	= userService.getUserCount(queryUserName,queryUserRole);
        //总页数
        PageSupport pages=new PageSupport();
        pages.setCurrentPageNo(currentPageNo);
        pages.setPageSize(pageSize);
        pages.setTotalCount(totalCount);

        int totalPageCount = pages.getTotalPageCount();

        //控制首页和尾页
        if(currentPageNo < 1){
   
            currentPageNo = 1;
        }else if(currentPageNo > totalPageCount){
   
            currentPageNo = totalPageCount;
        }


        //获取用户列表展示
        userList = userService.getUserList(queryUserName,queryUserRole,currentPageNo, pageSize);
        request.setAttribute("userList", userList);
        List<Role> roleList = null;
        RoleService roleService = new RoleServiceImpl();
        roleList = roleService.getRoleList();
        request.setAttribute("roleList", roleList);
        request.setAttribute("queryUserName", queryUserName);
        request.setAttribute("queryUserRole", queryUserRole);
        request.setAttribute("totalPageCount", totalPageCount);
        request.setAttribute("totalCount", totalCount);
        request.setAttribute("currentPageNo", currentPageNo);
        request.getRequestDispatcher("userlist.jsp").forward(request, response);
    }

用户管理实现(增删改)

  • 一切的增删改都需要处理事务,下面是一个增加的使用事务的例子:
public boolean add(User user) {
   
		// TODO Auto-generated method stub
		
		boolean flag = false;
		Connection connection = null;
		try {
   
			connection = BaseDao.getConnection();
			connection.setAutoCommit(false);//开启JDBC事务管理
			int updateRows = userDao.add(connection,user);
			connection.commit();
			if(updateRows > 0){
   
				flag = true;
				System.out.println("add success!");
			}else{
   
				System.out.println("add failed!");
			}
			
		} catch (Exception e) {
   
			e.printStackTrace();
			try {
   
				System.out.println("rollback==================");
				//如果执行出错就回滚
				connection.rollback();
			} catch (SQLException e1) {
   
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
		}finally{
   
			//在service层进行connection连接的关闭
			BaseDao.closeResource(connection, null, null);
		}
		return flag;
	}

供应商管理、订单管理

供应商管理、订单管理,和用户管理一样,也分查询和增删改两部分。实施方式也大体类似


转载:https://blog.csdn.net/qq_42647047/article/details/116503457
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