B站狂神说 - Eclipse - SMBMS项目实验

忘是亡心i 2023-03-14 05:53 15阅读 0赞

## 源码在最后 ##

### 文章目录 ###

*   *  SMBMS(超市管理项目)
     *   *  搭建项目准备工作
         *  登录功能实现
         *  登录功能优化
         *  登录拦截优化
         *  密码修改
         *  优化密码修改使用Ajax
         *  用户管理实现
         *   *  1、获取用户数量
             *  2、获取用户列表
             *  3、获取角色操作
             *  4、用户显示的Servlet
         *  无框架版源码
         *  SSM框架版源码

## SMBMS(超市管理项目) ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70]

数据库：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 1]  
**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 ###

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…
5.  构建项目包结构  
    ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 2]
6.  编写实体类  
    ROM映射:表-类映射
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）
    
        driver=com.mysql.jdbc.Driver
        #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://127.0.0.1:3306/smbms?useSSL=false&useUnicode=true&characterEncoding=utf-8
        user=root
        password=root
    
    2、编写数据库的公共类

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

1.  导入静态资源

### 登录功能实现 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 3]

1.  编写前端页面
2.  设置首页  
    1.设置欢迎首页

<welcome-file-list>
        <welcome-file>login.jsp</welcome-file>
      </welcome-file-list>

1.  编写dao层登录用户登录的接口

public User getLoginUser(Connection connection, String userCode) throws Exception;

1.  编写dao层接口的实现类

import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    
    import dao.BaseDao;
    import pojo.User;
    
    public class UserDaoImpl implements UserDao{ 
    	//持久层只做查询数据库的内容
    	public User getLoginUser(Connection connection, String userCode) throws Exception{ 
    		//准备三个对象
    		PreparedStatement pstm = null;
    		ResultSet rs = null;
    		User user = null;
    		//判断是否连接成功
    		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"));
    			}
    			BaseDao.closeResource(null, pstm, rs);
    		}
    		return user;
    	}	
    }

1.  业务层接口

//用户登录
    public User login(String userCode, String userPassword);

1.  业务层实现类

import java.sql.Connection;
    
    //import org.junit.Test;
    
    import dao.BaseDao;
    import dao.user.UserDao;
    import dao.user.UserDaoImpl;
    import pojo.User;
    
    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();
    	}
    	
    	public User login(String userCode,String userPassword) { 
    		// TODO Auto-generated method stub
    		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) { 
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}finally{ 
    			BaseDao.closeResource(connection, null, null);
    		}
    		return user;
    	}
    	
    	/*@Test public void test() { UserServiceImpl userService = new UserServiceImpl(); String userCode = "admin"; String userPassword = "12345678"; User admin = userService.login(userCode, userPassword); System.out.println(admin.getUserPassword()); } */
    }

1.  编写Servlet

import java.io.IOException;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import pojo.User;
    import util.Constants;
    import service.user.UserService;
    import service.user.UserServiceImpl;
    
    @SuppressWarnings("serial")
    public class LoginServlet extends HttpServlet{ 
    	//接受用户参数、调用业务层、转发视图
    	@Override
    	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
    		// TODO 自动生成的方法存根
    		
    		System.out.println("login ============ " );
    		//获取用户名和密码
    		String userCode = req.getParameter("userCode");
    		String userPassword = req.getParameter("userPassword");
    		//调用service方法，进行用户匹配
    		UserService userService = new UserServiceImpl();
    		User user = userService.login(userCode,userPassword);
    		if(null != user){ //登录成功
    			//放入session
    			req.getSession().setAttribute(Constants.USER_SESSION,user);
    			//页面跳转（frame.jsp）
    			resp.sendRedirect("jsp/frame.jsp");
    		}else{ 
    			//页面跳转（login.jsp）带出提示信息--转发
    			req.setAttribute("error", "用户名或密码不正确");
    			req.getRequestDispatcher("login.jsp").forward(req,resp);
    		}
    	}
    	@Override
    	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
    		// TODO 自动生成的方法存根
    		doGet(req, resp);
    	}
    }

1.  注册Servlet

<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>

1.  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

public class LogoutServlet extends HttpServlet { 
    
    	public void doPOST(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException { 
    		doGet(request, response);
    	}
    
    	public void doGet(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException { 
    		//清除session
    		request.getSession().removeAttribute(Constants.USER_SESSION);
    		response.sendRedirect(request.getContextPath()+"/login.jsp");//返回登录页面
    	}
    
    }

注册xml

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

### 登录拦截优化 ###

编写一个过滤器，并注册

import java.io.IOException;
    
    import javax.servlet.*;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import pojo.User;
    import util.Constants;
    
    public class SysFilter implements Filter{ 
    	public void init(FilterConfig filterConfig) throws ServletException{ 
    		
    	}
    
    	@Override
    	public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain)
    			throws IOException, ServletException { 
    		// TODO 自动生成的方法存根
    		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("/smbms/error.jsp");
    		}else { 
    			chain.doFilter(req, resp);
    		}
    	}
    
    	@Override
    	public void destroy() { 
    		// TODO 自动生成的方法存根
    		
    	}
    }

注册xml

<filter>
    	<filter-name>SysFilter</filter-name>
    	<filter-class>filter.SysFilter</filter-class>
    </filter> 
    <filter-mapping>
    	<filter-name>SysFilter</filter-name>
    	<url-pattern>/jsp/*</url-pattern>
    </filter-mapping>

测试，登录，注销，权限，都要保证OK

### 密码修改 ###

1.  导入前端素材

1.  写项目，建议从底层向上写  
    ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 4]
2.  UserDao接口

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

1.  UserDao接口实现类

@Override//修改当前密码
    	public int updatePwd(Connection connection, int id, int password) throws Exception { 
    		// TODO 自动生成的方法存根
    		PreparedStatement pstm = null;
    		int execute =0;
    		if(connection!=null) { 
    			String sql = "update smbms_user set = userPassword = ? where id = ?";
    			Object[] params = { password,id};
    			execute = BaseDao.execute(connection, pstm, sql, params);
    			BaseDao.closeResource(null, pstm, null);
    		}
    		return execute;			
    	}

1.  UserService层

public boolean updatePwd(int id,int password)throws SQLException, Exception;

1.  UserService实现类

public boolean updatePwd(int id, int password) throws SQLException, Exception { 
    		// TODO 自动生成的方法存根
    		Connection connection = null;
    		boolean flag = false;
    		//修改密码
    		try { 
    			connection = BaseDao.getConnection();
    			if(userDao.updatePwd(connection, id, password)>0) { 
    				flag = true;
    			}
    		} catch (SQLException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		} finally { 
    			BaseDao.closeResource(connection, null, null);
    			
    		}
    		return flag;
    	}

1.  servlet记得实现复用，要提取出方法！  
    在 **dao层** 和 **service层** 自己写映射类和实现类  
    下面是 **servlet层** 的主体

public class UserServlet extends HttpServlet { 
    	@Override
    	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
    		// TODO 自动生成的方法存根
    		String method = req.getParameter("method");
    		if (method != "savepwd" && method != null) { 
    			this.updatePwd(req, resp);
    		}
    		//实现复用~~~~~~
    		// 想添加新的增删改查，直接用if(method != "savepwd" && method != null);
    	}
    
    	@Override
    	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
    		// TODO 自动生成的方法存根
    		doGet(req, resp);
    	}
    
    	public void updatePwd(HttpServletRequest req, HttpServletResponse resp) { 
    		// 通过session获得用户id
    		Object o = req.getSession().getAttribute(Constants.USER_SESSION);
    		String newpassword = req.getParameter("newpassword");
    		boolean flag = false;
    		if (o != null && newpassword != null) { 
    			UserService userService = new UserServiceImpl();
    
    			try { 
    				flag = userService.updatePwd(((User) o).getId(), newpassword);
    			} catch (SQLException e) { 
    				// TODO 自动生成的 catch 块
    				e.printStackTrace();
    			} catch (Exception e) { 
    				// TODO 自动生成的 catch 块
    				e.printStackTrace();
    			}
    			if (flag) { 
    				req.setAttribute("message", "密码修改成功，请退出，使用新密码登录");
    				// 密码修改成功,移除session(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");
    			}
    
    		} else { 
    			// 密码修改有问题
    			req.setAttribute("message", "新密码有问题");
    		}
    		try { 
    			req.getRequestDispatcher("/jsp/pwdmodify.jsp").forward(req, resp);
    		} catch (ServletException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		} catch (IOException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		}
    	}
    }

注册xml

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

1.  测试

### 优化密码修改使用Ajax ###

1.  阿里巴巴的fastjson

<dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>fastjson</artifactId>
        <version>1.2.68</version>
    </dependency>

1.  后台代码修改

导入阿里的包

import java.io.IOException;
    import java.io.PrintWriter;
    //import java.io.Writer;
    import java.sql.SQLException;
    import java.util.HashMap;
    import java.util.Map;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import com.mysql.cj.util.StringUtils;
    import com.mysql.cj.xdevapi.JsonArray;
    
    //import com.mysql.cj.util.StringUtils;
    
    import pojo.User;
    import service.user.UserService;
    import service.user.UserServiceImpl;
    import util.Constants;
    
    @SuppressWarnings("serial")
    public class UserServlet extends HttpServlet { 
    	@Override
    	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
    		// TODO 自动生成的方法存根
    		String method = req.getParameter("method");
    		if (method.equals( "savepwd") && method != null) { 
    			this.updatePwd(req, resp);
    		}else if (method.equals( "pwdmodify") && method != null) { 
    			
    		}
    		// 想添加新的增删改查，直接用if(method != "savepwd" && method != null);
    	}
    
    	@Override
    	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
    		// TODO 自动生成的方法存根
    		doGet(req, resp);
    	}
    
    	public void updatePwd(HttpServletRequest req, HttpServletResponse resp) { 
    		// 通过session获得用户id
    		Object o = req.getSession().getAttribute(Constants.USER_SESSION);
    		String newpassword = req.getParameter("newpassword");
    		boolean flag = false;
    		if (o != null && newpassword != null) { 
    			UserService userService = new UserServiceImpl();
    
    			try { 
    				flag = userService.updatePwd(((User) o).getId(), newpassword);
    			} catch (SQLException e) { 
    				// TODO 自动生成的 catch 块
    				e.printStackTrace();
    			} catch (Exception e) { 
    				// TODO 自动生成的 catch 块
    				e.printStackTrace();
    			}
    			if (flag) { 
    				req.setAttribute("message", "密码修改成功，请退出，使用新密码登录");
    				// 密码修改成功,移除session(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");
    			}
    
    		} else { 
    			// 密码修改有问题
    			req.setAttribute("message", "新密码有问题");
    		}
    		try { 
    			req.getRequestDispatcher("/jsp/pwdmodify.jsp").forward(req, resp);
    		} catch (ServletException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		} catch (IOException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		}
    	}
    
    	public void pqdmodify(HttpServletRequest req, HttpServletResponse resp) { 
    		// 通过session获得用户id
    		Object o = req.getSession().getAttribute(Constants.USER_SESSION);
    		String oldpassword = req.getParameter("oldpassword");
    		
    		Map<String, String> resultMap = new HashMap<String, String>();
    		if(o==null) { //session失效，session过期了
    			resultMap.put("result","seesionerror");
    		}else if(StringUtils.isNullOrEmpty(oldpassword)){ //输入密码为空
    			resultMap.put("result","error");
    		}else { //
    			String userPassword = ((User)o).getUserPassword();//seesion中的用户密码
    			if(oldpassword.equals(userPassword)) { 
    				resultMap.put("result","true");
    			}else { 
    				resultMap.put("result","false");
    			}
    		}
    		
    		
    		try { 
    			resp.setContentType("application/josn");
    			PrintWriter writer = resp.getWriter();
    			/* * resultMap = ["result","sessionerror","result",error] * josn格式={key,value */
    			//writer.write(JSONArray.toJSONString(resultMap));
    			writer.write(JsonArray.class.toString());
    			writer.flush();
    			writer.close();
    		} catch (IOException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		}
    	}
    }

1.  测试

### 用户管理实现 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 5]

1.  导入分页的工具类-PageSupport
2.  用户列表页面导入-userlist.jsp

#### 1、获取用户数量 ####

1.  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;

1.  UserDaoImpl

@Override
    	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){ 
    			StringBuffer sql = new StringBuffer();
    			sql.append("select count(1) as count 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);
    			}
    			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");
    			}
    			BaseDao.closeResource(null, pstm, rs);
    		}
    		return count;
    	}

1.  UserService

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

1.  UserServiceImpl

//查询记录数
    	@Override
    	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);
    		}
    		//System.out.println("count"+count);
    		return count;
    	}

#### 2、获取用户列表 ####

1.UserDao

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

1.  UserDaoImpl

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

1.  UserService

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

1.  UserServiceImpl

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

#### 3、获取角色操作 ####

为了我们的职责统一，我们可以把**角色的操作**单独放在一个包中，和pojo类对应。。。

1.  RoleDao

//获取角色列表
    		public List<Role> getRoleList(Connection connection)throws Exception;

1.  RoleDaoIpml

public class RoleDaoImpl implements RoleDao { 
    
    	@Override
    	public List<Role> getRoleList(Connection connection) throws Exception { 
    		PreparedStatement pstm = null;
    		ResultSet rs = null;
    		List<Role> roleList = new ArrayList<Role>();
    		if (connection != null) { 
    			String sql = "select * from smbms_role";
    			Object[] params = { };
    			rs = BaseDao.execute(connection, pstm, rs, sql, params);
    			while (rs.next()) { 
    				Role _role = new Role();
    				_role.setId(rs.getInt("id"));
    				_role.setRoleCode(rs.getString("roleCode"));
    				_role.setRoleName(rs.getString("roleName"));
    				roleList.add(_role);
    			}
    			BaseDao.closeResource(null, pstm, rs);
    		}
    
    		return roleList;
    	}
    }

1.  RoleService

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

1.  RoleServiceIpml

public class RoleServiceImpl implements RoleService{ 
    	
    	private RoleDao roleDao;
    	
    	public RoleServiceImpl(){ 
    		roleDao = new RoleDaoImpl();
    	}
    	
    	@Override
    	public List<Role> getRoleList() { 
    		Connection connection = null;
    		List<Role> roleList = null;
    		try { 
    			connection = BaseDao.getConnection();
    			roleList = roleDao.getRoleList(connection);
    		} catch (Exception e) { 
    			e.printStackTrace();
    		}finally{ 
    			BaseDao.closeResource(connection, null, null);
    		}
    		return roleList;
    	}
    	
    }

#### 4、用户显示的Servlet ####

1.  获取用户前端的数据（查询）
2.  判断请求是否需要执行，看参数的值判断
3.  为了实现分页，需要计算出当前页面和总页面，页面大小…
4.  用户列表展示
5.  返回前端

//重点、难点
    	private void query(HttpServletRequest req, HttpServletResponse resp) { 
    		// TODO 自动生成的方法存根
    		//查询用户列表
    		//从前端获取数据
    		//查询用户列表
    		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	= userService.getUserCount(queryUserName,queryUserRole);
    			
    		//总页数支持
    		PageSupport pageSupport = new PageSupport();
    		pageSupport.setCurrentPageNo(currentPageNo);
    		pageSupport.setPageSize(pageSize);
    		pageSupport.setTotalCount(totalCount);
    		
    		int totalPageCount =pageSupport.getTotalPageCount();//总共有几页
    		//(totalCount+pageSize-1/pageSize)取整
    		// pageSupport.getTotalCount()
    		
    		//System.out.println("totalCount ="+totalCount);
    		//System.out.println("pageSize ="+pageSize);
    		//System.out.println("totalPageCount ="+totalPageCount);
    		//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;
    		}
    		
    		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) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		} catch (IOException e) { 
    			// TODO 自动生成的 catch 块
    			e.printStackTrace();
    		}
    
    	}

小黄鸭调试法：自言自语

**项目原理流程图：**  
![项目原理流程图][format_png]  
*剩下的手打一遍，然后各种打错排查，，，  
虽然不建议 ，但还是直接导入文件算了，粘贴复制也行0-0*（前提是自己先码一遍）

### 无框架版源码 ###

SMBMS项目源码链接：  
[Eclipse版（个人手打版，已排错，可运行）  
https://www.lanzoux.com/iGLJTdusuyf  
][Eclipse_ https_www.lanzoux.com_iGLJTdusuyf]  
*6月20号，补上了之前漏掉的smbms的MySQL数据库（链接已更新）*

**IDEA版（狂神原版）- 进群拿–>狂神说Java交流群：1063621833**

--------------------

### SSM框架版源码 ###

*2021年5月1号*  
IDEA工具-SMBMS项目的**SSM框架**整合版  
[https://blog.csdn.net/bell\_love/article/details/116284289][https_blog.csdn.net_bell_love_article_details_116284289]

.  
想学习 Docker 技术的下边请  
[【狂神说Java】Docker最新超详细版教程通俗易懂  
https://www.bilibili.com/video/BV1og4y1q7M4][Java_Docker_ https_www.bilibili.com_video_BV1og4y1q7M4]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70]: /images/20230312/1d984f46c2d34169b463a0de55b77e3b.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 1]: /images/20230312/3064020fcbb94a63972a3d1441b7a2d7.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 2]: /images/20230312/e8031766bfd742a0abe641cc6a9738a1.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 3]: /images/20230312/eadd9bfddb76440e81fbb48ea120d785.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 4]: /images/20230312/612830961a5a433ebc2cacb901342d4e.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2JlbGxfbG92ZQ_size_16_color_FFFFFF_t_70 5]: /images/20230312/ea9284410e2c4a2a93d37862f2047a02.png
[format_png]: /images/20230312/4bc107a42cc3491d974cd86ec049a0d5.png
[Eclipse_ https_www.lanzoux.com_iGLJTdusuyf]: https://www.lanzoux.com/iGLJTdusuyf
[https_blog.csdn.net_bell_love_article_details_116284289]: https://blog.csdn.net/bell_love/article/details/116284289
[Java_Docker_ https_www.bilibili.com_video_BV1og4y1q7M4]: https://www.bilibili.com/video/BV1og4y1q7M4