在DButil.java文件定义连接数据库的静态方法getConnection()

在ClassDao.java文件中定义让数据库添加数据的方法Add()

.在WebContent目录下建立addClass.jsp文件，在此jsp文件中添加表单，通过表单将输入的信息提交至class.jsp,然后进行判断输入的格式是否正确，然后写入数据库

DButil.java

package com.jaovo.msg.Util;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.util.Properties;import javax.naming.Context;import javax.naming.InitialContext;import javax.sql.DataSource;public class DBUtil {    public static Connection getConnection() {                        try {            Class.forName("com.mysql.jdbc.Driver").newInstance();        } catch (InstantiationException | IllegalAccessException                | ClassNotFoundException e1) {            e1.printStackTrace();        }                 String user = "root";        String password = "root";        String url = "jdbc:mysql://localhost:3306/wei";        Connection connection = null;        try {            connection = DriverManager.getConnection(url, user, password);        } catch (SQLException e) {            e.printStackTrace();        }        return connection;    }    public static void close(Connection connection) {        try {            if (connection != null) {                connection.close();            }        } catch (SQLException e) {            e.printStackTrace();        }    }    public static void close(PreparedStatement preparedStatement) {        try {            if (preparedStatement != null) {                preparedStatement.close();            }        } catch (SQLException e) {            e.printStackTrace();        }    }    public static void close(ResultSet resultSet) {        try {            if (resultSet != null) {                resultSet.close();            }        } catch (SQLException e) {            e.printStackTrace();        }    }}

ClassDao.java

package com.jaovo.msg.dao;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import com.jaovo.msg.Util.DBUtil;import com.jaovo.msg.model.Class;import com.jaovo.msg.dao.ClassDao;public class ClassDao {        public void add(Class course) {            //或得数据库连接对象            Connection connection = DBUtil.getConnection();            //准备SQL语句            String sql =null; //"select count(*) from tab_user where username=?";            //声明数据库准备执行对象,但是没有实例化,赋值为空            PreparedStatement preparedStatement = null;            //声明一个结果集对象,用于接收,我们我们pre执行后,发送到数据库的sql语句,然后数据库执行,在然后返回到我们程序端的            //结果集对象            //ResultSet resultSet = null;          数据库,让数据库处理,然后把结果集返回回来,用resultSet.                //这个是重点,这里才是真正连接数据库,然后执行的地方                resultSet = preparedStatement.executeQuery();                while(resultSet.next()) {                    if(resultSet.getInt(1)>0)                        throw new UserException("用户已存在");                                    }*/            try {                sql="insert into tab_course(classname,classtea,classspace) value(?,?,?)";                preparedStatement = connection.prepareStatement(sql);                preparedStatement.setString(1, course.getClassname());                preparedStatement.setString(2, course.getClasstea());                preparedStatement.setString(3, course.getClassplace());                preparedStatement.executeUpdate();            } catch (SQLException e) {                e.printStackTrace();            } finally {                //DBUtil.close(resultSet);                DBUtil.close(preparedStatement);                DBUtil.close(connection);            }                    }}

addClass.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>
     
     
      <%=request.getAttribute("result") %>
      
       
                    
         
                          
课程名
                          
  
                     
                     
                          
任课老师
                          
  
                     
                     
                          
课堂地点
                          
  
                     
                     
                          
                       
        
       
      
     

class.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>     <%@ page import="com.jaovo.msg.model.Class"%>    <%@ page import="com.jaovo.msg.dao.ClassDao"%><%    String classname = request.getParameter("classname");    String classtea = request.getParameter("classtea");    String classspace = request.getParameter("classspace");    if(classtea.equals("王建民")||classtea.equals("刘丹")||classtea.equals("刘立嘉")||classtea.equals("王辉")||classtea.equals("杨子光"))    {    }    else    {        request.setAttribute("result","请输入在职老师");%>
     <%    }if(classspace.startsWith("基教")||classspace.startsWith("一教")||classspace.startsWith("二教")||classspace.startsWith("三教")){    }else{    request.setAttribute("result","请输入正确地点");%>
     <%}    Class course=new Class();    course.setClassname(classname);    course.setClasstea(classtea);    course.setClassplace(classspace);    ClassDao classDao=new ClassDao();    classDao.add(course);    request.setAttribute("result","课程添加成功");%>
     

运行结果截图