Servlet+纯java+MySQL实现课程信息的增删改查

时间：2024-01-10 09:31:02

Dbutil:

package com.zh.util;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.Statement;

import java.sql.SQLException;

public class DButil {

    public static Connection getConnection(){

        Connection conn = null;

        try {

        Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

        String url="jdbc:mysql://localhost:3306/teacher_class?serverTimezone=UTC";

        conn=DriverManager.getConnection(url, "root", "hao19990507.");

        }catch (Exception e){

            e.printStackTrace();

        }

        return conn;

    }

    public static void close(Statement sta,Connection con){

        if (sta != null) {

            try {

                sta.close();

            } catch (SQLException e) {

                e.printStackTrace();

            }

        }

        if (con != null) {

            try {

                con.close();

            } catch (SQLException e) {

                e.printStackTrace();

            }

        }

    }

    public static void close(ResultSet rs,Statement sta,Connection con){

        if (rs != null) {

            try {

                rs.close();

            } catch (SQLException e) {

                e.printStackTrace();

            }

        }

        if (sta != null) {

            try {

                sta.close();

            } catch (SQLException e) {

                e.printStackTrace();

            }

        }

        if (con != null) {

            try {

                con.close();

            } catch (SQLException e) {

                e.printStackTrace();

            }

        }

    }

}

bean:

package com.zh.entity;

    public class bean {

    private String place;

    private String teacher_name;

    private String class_name;

    public String get_place() {

        return place;

    }

    public void set_place(String place) {

        this.place=place;

    }

    public String get_teacher_name() {

        return teacher_name;

    }

    public void set_teacher_name(String teacher_name) {

        this.teacher_name=teacher_name;

    }

    public String get_class_name() {

        return class_name;

    }

    public void set_class_name(String class_name) {

        this.class_name=class_name;

    }

    public bean() {};

    public bean(String place,String teacher_name,String class_name) {

        this.place=place;

        this.teacher_name=teacher_name;

        this.class_name=class_name;

        }

}

data_dao:

package com.zh.dao;

import java.util.*;

import java.sql.*;

import com.zh.entity.*;

import com.zh.util.*;

import java.sql.*;

public class data_dao {

    /*增加

     *

     */

public void add(bean Bean) {

    String sql="insert into class_message values('"+Bean.get_place()+"','"+Bean.get_teacher_name()+"','"+Bean.get_class_name()+"')";

    Connection conn = DButil.getConnection();

    Statement state = null;

    try {

        state = conn.createStatement();

        state.executeUpdate(sql);

    } catch (Exception e) {

        e.printStackTrace();

    }

}

/*删除

 *

 */

public void deleteByteacher_name(String teacher_name) {

    boolean f=false;

    String sql="delete from class_message where teacher_name='"+teacher_name+"'";

    Connection conn=DButil.getConnection();

    Statement state = null;

    try {

        state = conn.createStatement();

        state.executeUpdate(sql);

    } catch (SQLException e) {

        e.printStackTrace();

    } 

    }

         /* 修改

         *

         */

public void updata(bean b) {

    String sql="updata class_message set place='"+b.get_place()+"', teacher_name='"+b.get_teacher_name()+"',class_name='"+b.get_class_name()+"' where teacher_name='"+b.get_teacher_name()+"'";

    Connection conn=DButil.getConnection();

    Statement state = null;

    try {

        state = conn.createStatement();

        state.executeUpdate(sql);

    } catch (SQLException e) {

        e.printStackTrace();

    } 

}

/**

 * 验证课程名称是否唯一

 */

public List<bean> isOnly_class_name(String class_name) {

    List list=new ArrayList<bean>();

    String sql="select name from class_message where class_name='"+class_name+"'";

    Connection conn=DButil.getConnection();

    Statement state=null;

    ResultSet rs = null;

    try {

        state = conn.createStatement();

        rs = state.executeQuery(sql);

        while(rs.next()) {

            String class_name1=rs.getString("class_name");

            String teacher_name=rs.getString("teacher_name");

            String place=rs.getString("place");

            bean b=new bean(place,teacher_name,class_name1);

            list.add(b);

        }

    } catch (SQLException e) {

    e.printStackTrace();

}

    return list;

}

/**

 * 通过teacher_name获得一个bean对象

 */

public bean findByteacher_name(String teacher_name) {

        Connection conn=null;

    Statement state=null;

    try {

        conn=DButil.getConnection();

        String sql="select*from class_message where teacher_name='"+teacher_name+"'";

        state=conn.createStatement();

        ResultSet rs=state.executeQuery(sql);

        bean u=new bean();;

        while(rs.next()) {

            String t_name=rs.getString("teacher_name");

            String c_name=rs.getString("class_name");

            String place=rs.getString("place");

            u.set_class_name(c_name);

            u.set_place(place);

            u.set_teacher_name(t_name);

            return u;

        }

    }catch (Exception e) {

        e.printStackTrace();

        }

return null;

}

/*

 * 显示全部

 */

public List<bean> findAll(){

    Connection conn=DButil.getConnection();

    List<bean> list=new ArrayList<bean>();

    bean b=null;

    try {

    Statement sta=conn.createStatement();

    String sql="select * from class_message";

    ResultSet rs=sta.executeQuery(sql);

        while(rs.next()) {

            b=new bean();

            String t_name,c_name,place;

            t_name=rs.getString("teacher_name");

            c_name=rs.getString("c_name");

            place=rs.getString("place");

            b.set_class_name(c_name);

            b.set_place(place);

            b.set_teacher_name(t_name);

            list.add(b);

        }

    }catch (Exception e) {

        e.printStackTrace();

    }

    for(int i=0;i<list.size();i++) {

        bean br=(bean)list.get(i);

        System.out.println(br.get_teacher_name());

    }

    return list;

}

}

Userservice:

package com.zh.service;

import java.util.*;

import com.zh.dao.*;

import com.zh.entity.*;

public class Userservice {

public boolean insertUser(String place,String teacher_name,String class_name) {

    data_dao dao=new data_dao();

    bean b=new bean();

    b.set_class_name(class_name);

    b.set_place(place);

    b.set_teacher_name(teacher_name);

    try {

    dao.add(b);

    return true;

    }catch (Exception e) {

        e.printStackTrace();

        return false;

    }

}

public boolean deleteUser(String teacher_name) {

    data_dao dao=new data_dao();

    bean b=dao.findByteacher_name(teacher_name);

    if(b!=null) {

        dao.deleteByteacher_name(teacher_name);

        return true;

    }else

        return false;

}

public boolean updataByteacher_name(String place,String class_name,String teacher_name) {

    data_dao dao=new data_dao();

    bean b=new bean(place,class_name,teacher_name);

    try {

        dao.updata(b);

        return true;

    }catch (Exception e) {

        e.printStackTrace();

        return false;

    }

    }

public boolean isOnly_classname(String class_name) {

    data_dao dao=new data_dao();

    try {

        List list=dao.isOnly_class_name(class_name);

        if(list.size()>1)

            return true;

        else

            return false;

    }catch (Exception e) {

        e.printStackTrace();

        return false;

    }

}

public List<bean> findAll_user(){

    data_dao dao=new data_dao();

    List list=dao.findAll();

    return list;

}

}

DeleteServlet:

package com.zh.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.zh.service.*;

@WebServlet("/DeleteServlet")

public class DeleteServlet extends HttpServlet {

       protected void service(HttpServletRequest arg0,HttpServletResponse arg1)

               throws ServletException ,IOException{

           arg1.setContentType("text/html");

           arg0.setCharacterEncoding("GBK");

           arg1.setCharacterEncoding("GBK");

           String name=arg0.getParameter("teacher_name");

           Userservice service =new Userservice();

           service.deleteUser(name);

           try {

               arg0.getRequestDispatcher("/query").forward(arg0, arg1);

           }catch (Exception e) {

               e.printStackTrace();

           }

       }

   }

InsertServlet:

package com.zh.servlet;

import java.io.IOException;

import java.io.PrintWriter;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.zh.service.*;

@WebServlet("/InsertServlet")

public class InsertServlet extends HttpServlet {

    protected void service(HttpServletRequest req,HttpServletResponse res)

            throws ServletException,IOException {

        res.setContentType("text/html");

        req.setCharacterEncoding("GBK");

        res.setCharacterEncoding("GBK");

        String place=req.getParameter("place");

        String teacher_name=req.getParameter("teacher_name");

        String class_name=req.getParameter("class_name");

        PrintWriter pw=res.getWriter();

        Userservice service=new Userservice();

        try {

            service.insertUser(place, teacher_name, class_name);

            pw.println("新增信息成功！");

            req.getRequestDispatcher("/query").forward(req, res);;

        }catch (Exception e) {

            e.printStackTrace();

            req.getRequestDispatcher("/insert.html").forward(req, res);

        }

    }

}

QueryServlet:

package com.zh.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.io.PrintWriter;

import com.zh.entity.*;

import com.zh.service.*;

import java.util.*;

@WebServlet("/QueryServlet")

public class QueryServlet extends HttpServlet {

    protected void service(HttpServletRequest req,HttpServletResponse res)

            throws ServletException,IOException {

        res.setContentType("text/html");

        req.setCharacterEncoding("GBK");

        res.setCharacterEncoding("GBK");

        PrintWriter pw=res.getWriter();

        Userservice service=new Userservice();

        List list=service.findAll_user();

        pw.println("<html>");

        pw.println("<head>");

        pw.println("</head>");

        pw.println("<body>");

        pw.println("<table border='1' bordercolor='red' align='center'");

        pw.println("<tr>");

        pw.println("<td>");

        pw.println("地点");

        pw.println("</td>");

        pw.println("<td>");

        pw.println("教师名");

        pw.println("</td>");

        pw.println("<td>");

        pw.println("课程名");

        pw.println("</td>");

        pw.println("</tr>");

        for(int i=0;i<list.size();i++) {

        bean b=(bean) list.get(i);

        pw.println("<tr>");

        pw.println("<td>");

        pw.println(b.get_place());

        pw.println("</td>");

        pw.println("<td>");

        pw.println(b.get_teacher_name());

        pw.println("</td>");

        pw.println("<td>");

        pw.println(b.get_class_name());

        pw.println("/<td>");

        pw.println("<a href='/Web_operation1/delete?teacher_name="+b.get_teacher_name()+"'> 删 除   </a>||<a href='/Web_operation1/updata.html'>修改信息</a>" );

                pw.println("</td>");

                pw.println("</tr>");

        }

        pw.println("</table>");

        pw.println("</body>");

        pw.println("</html>");

        pw.flush();

        pw.close();

}

}

UpdateServlet:

package com.zh.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.io.PrintWriter;

import com.zh.service.*;

@WebServlet("/UpdataServlet")

public class UpdateServlet extends HttpServlet {

protected void service(HttpServletRequest req,HttpServletResponse res)

        throws ServletException,IOException {

    res.setContentType("text/html");

    req.setCharacterEncoding("GBK");

    res.setCharacterEncoding("GBK");

    PrintWriter pw=res.getWriter();

    Userservice service=new Userservice();

    String place=req.getParameter("place");

    String teacher_name=req.getParameter("teacher_name");

    String class_name=req.getParameter("class_name");

    try {

        if (service.updataByteacher_name(place, class_name, teacher_name)) {

            res.sendRedirect("/Web_operation1/query");

        }

    }catch (Exception e) {

        e.printStackTrace();

    }

}

}

insert.html:

<!DOCTYPE HTML PUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<meta charset="UTF-8">

<title>Insert </title>

</head>

<body>

<center>

<form action="/Web_operation1/insert"medthod="post">

   <table border ="1" bordercolor="red"align="center">

   <tr>

   <td>

     上课地点：

     </td>

     <td>

     <input type="text" name="place"/>

     </td>

     </tr>

   <tr>

   <td>

   任课教师：

   </td>

   <td>

   <input type="text" name="teacher_name"/>

   </td>

   </tr>

   <tr>

   <td>

   课程名称：

   </td>

   <td>

   <input type="text" name="class_name"/>;

   </td>

   </tr>

   </table>

   </form>

   </center>

</body>

</html>

update.html:

<!DOCTYPE HTML PUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<meta charset="UTF-8">

<title>update</title>

</head>

<body>

<center>

<form action="/Web_operation1/update" method="post">

<table border="1"bordercolor="red" align="center">

<tr>

<td> 上课地点：</td>

<td>

<input type="text" name="place">

</td>

</tr>

<tr>

<td> 任课教师：</td>

<td>

<input type="text" name="teacher_name">

</td>

</tr>

<tr>

<td> 课程名称：</td>

<td>

<input type="text"name="class_name">

</td>

</tr>

<tr>

 <td colspan="2"align="center">

 <input type="button" value="确认">

 </td>

 </tr>

</table>

</form>

</body>

</html>

web.xml:

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0">

  <display-name>Web_operation1</display-name>

  <welcome-file-list>

    <welcome-file>index.html</welcome-file>

    <welcome-file>index.htm</welcome-file>

    <welcome-file>index.jsp</welcome-file>

    <welcome-file>default.html</welcome-file>

    <welcome-file>default.htm</welcome-file>

    <welcome-file>default.jsp</welcome-file>

  </welcome-file-list>

  <servlet>

  <servlet-name>query</servlet-name>

  <servlet-class>com.zh.servlet.QueryServlet</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>query</servlet-name>

  <url-pattern>/query</url-pattern>

  </servlet-mapping>

  <servlet>

  <servlet-name>delete</servlet-name>

  <servlet-class>com.zh.servlet.DeleteServlet</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>delete</servlet-name>

  <url-pattern>/delete</url-pattern>

  </servlet-mapping>

  <servlet>

  <servlet-name>update</servlet-name>

  <servlet-class>com.zh.servlet.UpdateServlet</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>update</servlet-name>

  <url-pattern>/update</url-pattern>

  </servlet-mapping>

  <servlet>

  <servlet-name>insert</servlet-name>

  <servlet-class>com.zh.servlet.InsertServlet</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>insert</servlet-name>

  <url-pattern>/insert</url-pattern>

  </servlet-mapping>

</web-app>

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