Java后台+數據庫+Java web前端（新手）

本文轉載自查看原文 2018-12-19 20:48 13782 Java

實現簡單頁面上對數據的增刪改查：Java后台+數據庫表+Jsp前端網頁設計

項目下載鏈接：https://pan.baidu.com/s/1UvZ5fzFjxU-GELo9Th3nNg
提取碼：kvmc

GitHub源碼下載：https://github.com/yishengxiaobai/Java_Course

這里做一個簡單的學生課程信息管理系統，做之前一定要先有自己的思路，要不然對新手來說，很容易亂的。

通過本系統，同學們可以添加，刪除，查詢與修改課程上課地點和課程老師以及課程名稱等信息。

運行截圖：

數據庫設計：

首頁：

課程信息錄入：

課程信息修改：

課程信息刪除：（先查找后刪除）

課程信息查詢：

另有一完整的代碼可供參考，網頁版記賬本，鏈接https://www.cnblogs.com/sengzhao666/p/10449534.html

一.建立項目

1. 首先新建一個名為Course的Dynamic Web Project

取完名直接點擊完成，或者一直下一步直到完成。

2. 程序分五層

Dao:底層程序

Entity：實體層

Servlet：將界面與底層程序聯系起來

Service：可以理解為servlet層與dao層的中轉層

Util:連接數據庫

注意servlet層不是建立類，而是建立一個Servlet；其他包下均為類。

二.數據庫設計

三.系統功能分析

1. 添加

需要一個界面add.jsp

2. 刪除

首先需要根據名稱查找；deletebyName.jsp

查找后列出結果，刪除；delete.jsp

3. 修改

首先列出所有數據；list.jsp

修改界面；update.jsp

4. 查詢

查詢界面；select.jsp(模糊查詢)

顯示查詢結果界面；selectlist.jsp

四．實現增刪改查四項基本功能（以添加功能為例，其他思路相同）

功能解析：

add界面得到數據；

servlet層獲得數據；

Service層傳遞給dao底層程序；

最后dao層執行sql語句：

String sql = "insert into course(name, teacher, classroom) values('" + course.getName() + "','" + course.getTeacher() + "','" + course.getClassroom() + "')";

將數據添加進數據庫。

注：推薦寫程序時編寫順序也這么來：先想好系統功能，然后編寫前端jsp再一步一步往下推。

程序詳解：

添加界面add.jsp得到用戶鍵入的數據；

界面執行通過后，action="courseServlet?method=add" 三目運算符將method賦值為add；

Servlet層得到method，判斷method值；

String method = req.getParameter("method");
        if ("add".equals(method)) {
            add(req, resp);
        }

執行add函數。

servlet層add函數獲得界面數據：

String name = req.getParameter("name");
String teacher = req.getParameter("teacher");
String classroom = req.getParameter("classroom");
Course course= new Course(name, teacher, classroom);

調用service層函數：

 if(service.add(course)) {
            req.setAttribute("message", "添加成功");//setAttribute方法用於將內容保存在對象中，傳到下一個頁面中
            req.getRequestDispatcher("add.jsp").forward(req,resp);//getRequestDispatcher方法用於進入下一個頁面
        }

Service層傳遞給dao底層。

public  boolean add(Course course) {
        boolean bean=false;
        if(!dao.rename(course.getName())) {
         //檢查是否重名，否的話執行下一步
         dao.add(course);
         bean=true;
        }
        return bean;
}

Dao層執行添加功能：

String sql = "insert into course(name, teacher, classroom) values('" + course.getName() + "','" + course.getTeacher() + "','" + course.getClassroom() + "')";

五.源代碼：

實體層Course.Java:

package entity;

public class Course {

private int id;
    private String name;
    private String teacher;
    private String classroom;
    public void setId(int id) {
    this.id=id;
}
public int getId() {
    return id;
}
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getTeacher() {
        return teacher;
    }
    public void setTeacher(String teacher) {
        this.teacher = teacher;
    }
    public String getClassroom() {
        return classroom;
    }
    public void setClassroom(String classroom) {
        this.classroom = classroom;
    }

    public Course() {}

    public Course(String name, String teacher, String classroom) {
        this.name = name;
        this.teacher = teacher;
        this.classroom = classroom;
    }
}

servlet層代碼如下：

package servlet;
import java.io.IOException;
import java.util.List;

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 entity.Course;
import service.courseService;

/**
* Servlet implementation class courseServlet
*/
@WebServlet("/courseServlet")
public class courseServlet extends HttpServlet{
private static final long serialVersionUID = 1L;

courseService service=new courseService();

    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        /**
         * 方法選擇
         */
        req.setCharacterEncoding("utf-8");
        String method = req.getParameter("method");
        if ("add".equals(method)) {
            add(req, resp);
        } else if ("delete".equals(method)) {
            delete(req, resp);
        } else if ("update".equals(method)) {
            update(req, resp);
        } else if ("select".equals(method)) {
            select(req, resp);
        } else if ("getCoursebyName".equals(method)) {
        getCoursebyName(req, resp);
        } else if ("getCoursebyName2".equals(method)) {
        getCoursebyName2(req, resp);
        }   else if ("list".equals(method)) {
            list(req, resp);
        }
    }

    private void add(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException {
    //添加
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        String teacher = req.getParameter("teacher");
        String classroom = req.getParameter("classroom");
        Course course= new Course(name, teacher, classroom);

        //判斷是否重名
        if(service.add(course)) {
            req.setAttribute("message", "添加成功");//setAttribute方法用於將內容保存在對象中，傳到下一個頁面中
            req.getRequestDispatcher("add.jsp").forward(req,resp);//getRequestDispatcher方法用於進入下一個頁面
        } else {
            req.setAttribute("message", "課程名稱重復，請重新錄入");
            req.getRequestDispatcher("add.jsp").forward(req,resp);
        }
    }

    private void delete(HttpServletRequest req, HttpServletResponse resp)throws IOException, ServletException{
    // 刪除
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        service.delete(name);
        req.setAttribute("message", "課程信息刪除成功");
        req.getRequestDispatcher("deletebyName.jsp").forward(req,resp);
    }

    private void getCoursebyName2(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    /*
    * 通過名字得到
    * 跳轉至修改
    */
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        Course course =service.getCoursebyName(name);
        req.setAttribute("course", course);
        req.getRequestDispatcher("update.jsp").forward(req,resp);

    }

    private void getCoursebyName(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    /*
    * 通過名字查找
    * 跳轉至刪除
    */
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        Course course =service.getCoursebyName(name);
        if(course == null) {
            req.setAttribute("message", "查無此課程！");
            req.getRequestDispatcher("deletebyName.jsp").forward(req,resp);
        } else {
            req.setAttribute("course", course);
            req.getRequestDispatcher("delete.jsp").forward(req,resp);
        }
    }

    private void list(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    //列出全部信息
        req.setCharacterEncoding("utf-8");
        List<Course> course = service.list();
        req.setAttribute("courses",course);
        req.getRequestDispatcher("list.jsp").forward(req,resp);
    }

    private void update(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    //修改
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        String teacher = req.getParameter("teacher");
        String classroom = req.getParameter("classroom");
        Course course = new Course(name,teacher, classroom);
        int k=service.update(course);
        if(k==0) {
        req.setAttribute("message", "修改失敗");
   req.getRequestDispatcher("courseServlet?method=list").forward(req,resp);
        }else if(k==1){
        req.setAttribute("message", "修改成功");
        req.getRequestDispatcher("courseServlet?method=list").forward(req,resp);
        }
    }

    private void select(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
    //查找
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        String teacher = req.getParameter("teacher");
        String classroom = req.getParameter("classroom");
        List<Course> course = service.select(name, teacher, classroom);
        req.setAttribute("courses", course);
        req.getRequestDispatcher("selectlist.jsp").forward(req,resp);

    }
}

service層代碼如下：

package service;

import java.util.List;

import dao.Dao;
import entity.Course;

public class courseService{
    Dao dao=new Dao();
    public boolean add(Course course) {
        boolean bean=false;
        if(!dao.rename(course.getName())) {
        //檢查是否重名，否的話執行下一步
        dao.add(course);
        bean=true;
        }
        return bean;
    }
    public void delete(String name) {
    dao.delete(name);
    }
    public int update(Course course) {
    int f=0;
  if(dao.update(course)) {
   f=1;
  }
  return f;
    }

    public Course getCoursebyName(String name) {
    //通過Name得到一個Course
        return dao.getCoursebyName(name);
    }

    public List<Course> select(String name, String teacher, String classroom) {
    //查找
        return dao.select(name, teacher, classroom);
    }

    public List<Course> list() {
    //列出表中所有信息
        return dao.list();
    }
}

Dao層代碼如下：

package dao;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import entity.Course;
import util.Shujuku;

public class Dao {

/*
* 將函數設置為Boolean類型，只返回真值或假值給service層，方便
*/

public boolean rename(String name) {
  //搜索數據庫表course，檢查是否重名
  String sql = "select * from courses where name ='" + name + "'";
        Connection conn =Shujuku.conn() ;
        Statement st= null;
        ResultSet rs = null;
        boolean bean=false;
        try {
            st = conn.createStatement();
            rs = st.executeQuery(sql);
            while (rs.next()) {
            bean = true;
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            Shujuku.close(rs,st, conn);
        }
        return bean;
}

public boolean add(Course course) {
  //添加
   String sql = "insert into courses(name, teacher, classroom) values('" + course.getName() + "','" + course.getTeacher() + "','" + course.getClassroom() + "')";
      Connection conn =Shujuku.conn() ;
     Statement st= null;
      boolean bean = false;
         int a = 0;

         try {
             st = conn.createStatement();
             st.executeUpdate(sql);
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             Shujuku.close(st, conn);
         }

         if (a > 0) {
             bean = true;
         }
         return bean;

}

public boolean delete(String name) {
  // 通過名字刪除
  boolean f=false;
  String sql = "delete from courses where name ='" + name + "'";//刪除
  Connection conn = Shujuku.conn();
  Statement state = null;
  int a=0;
  try {
   state = conn.createStatement();
   a=state.executeUpdate(sql);
  }catch (Exception e) {
   e.printStackTrace();
  } finally {
   Shujuku.close(state, conn);
  }
  if(a>0) {
   f=true;
  }
  return f;
}

public boolean update(Course course) {
  // 修改
  String sql = "update courses set teacher='" + course.getTeacher() + "', classroom='" + course.getClassroom()+"'where name='"+course.getName()+"'";
  Connection conn = Shujuku.conn();
  Statement state = null;
  boolean f = false;
  int a = 0;

  try {
   state = conn.createStatement();
   a = state.executeUpdate(sql);
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   Shujuku.close(state, conn);
  }

  if (a > 0) {
   f = true;
  }
  return f;

}

public Course getCoursebyName(String name) {
   String sql = "select * from courses where name ='" + name + "'";
         Connection conn =Shujuku.conn() ;
         Statement st= null;
         ResultSet rs = null;
         Course course=null;
         try {
             st = conn.createStatement();
             rs = st.executeQuery(sql);
             while (rs.next()) {
                 String teacher = rs.getString("teacher");
                 String classroom = rs.getString("classroom");
                 course = new Course(name, teacher, classroom);
             }
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             Shujuku.close(rs,st, conn);
         }
         return course;
}

public List<Course> select(String name, String teacher, String classroom) {
String sql = "select * from courses where ";
   if (name !=null) {
    sql += "name like '%" + name + "% '";
   }else if(name==null) {
    sql += " ";
   }
   if (name !=null&&teacher !=null) {
             sql += "and teacher like '%" + teacher + "% '";
         }else if(name==null&&teacher !=null) {
    sql += "teacher like '%" + teacher + "% '";
   }else if(teacher==null) {
    sql += " ";
   }
   if ((name!=null||teacher !=null)&&classroom !=null) {
             sql += "and classroom like '%" + classroom + "%'";
         }else if(name==null&&teacher==null&&classroom !=null) {
    sql += "teacher like '%" + teacher + "% '";
   }else if(classroom==null) {
    sql += " ";
   }
         List<Course> list = new ArrayList<>();
         Connection conn =Shujuku.conn() ;
         Statement st= null;
         ResultSet rs = null;
         try {
             st = conn.createStatement();
             rs = st.executeQuery(sql);
             Course course=null;
             while (rs.next()) {
                 String name2 = rs.getString("name");
                 String teacher2 = rs.getString("teacher");
                 String classroom2 = rs.getString("classroom");
                 course= new Course(name2, teacher2, classroom2);
                 list.add(course);
             }
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             Shujuku.close(rs,st, conn);
         }
         return list;

}

public List<Course> list() {
  String sql = "select * from courses";
  List<Course> list = new ArrayList<>();
        Connection conn =Shujuku.conn() ;
        Statement st= null;
        ResultSet rs = null;
        try {
            st = conn.createStatement();
            rs = st.executeQuery(sql);
            Course course=null;
            while (rs.next()) {
                String name2 = rs.getString("name");
                String teacher2 = rs.getString("teacher");
                String classroom2 = rs.getString("classroom");
                course= new Course(name2, teacher2, classroom2);
                list.add(course);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            Shujuku.close(rs,st, conn);
        }
        return list;

}

數據庫連接信息放在util包內：（我這里用的是sql server 2008r2）

import java.sql.Connection;
import java.sql.DriverManager;

public class Shujuku {
     public static Connection conn(){
         String url="jdbc:sqlserver://localhost:1433;DatabaseName=YourShujukuName";//填寫你的數據庫名
         String userName="sa";//填寫你的用戶名，我的是sa
         String userPwd="tzk19991029";//填寫你的密碼,我的是tzk19991029
         Connection con=null;

  try{
      Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
      System.out.println("加載驅動成功！");

  }catch(Exception e){

           e.printStackTrace();

           System.out.println("加載驅動失敗！");
   }
 try{
    con=DriverManager.getConnection(url,userName,userPwd);
 System.out.println("連接數據庫成功！");
 }catch(Exception e){
        e.printStackTrace();
        System.out.print("SQL Server連接失敗！");
  }    
 return con;
}
}

二.網頁部分

index.jsp是首頁，代碼如下：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>首頁</title>
<style >
.a{
        font-size: 26px;
        margin-top: 20px;
    }
</style>
</head>
<body>
<div align="center">
<h1 style="color: red;">課程基本信息管理系統</h1>
        <div class="a">
            <a href="add.jsp">課程信息錄入</a>
        </div>
        <div class="a">
            <a href="courseServlet?method=list">課程信息修改</a>
        </div>
        <div class="a">
            <a href="deletebyName.jsp">課程信息刪除</a>
        </div>
        <div class="a">
            <a href="select.jsp">課程信息查詢</a>
        </div>
</div>
</body>
</html>

add.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<%
         Object message = request.getAttribute("message");
         if(message!=null && !"".equals(message)){
     
    %>
         <script type="text/javascript">
              alert("<%=request.getAttribute("message")%>");
         </script>
    <%} %>
    <div align="center">
        <h1 style="color: red;">課程信息錄入</h1>
        <a href="index.jsp">返回主頁</a>
        <form action="courseServlet?method=add" method="post" onsubmit="return check()">
            <div >
                課程名稱<input type="text" id="name" name="name"/>
            </div>
            <div >
                任課教師<input type="text" id="teacher" name="teacher" />
            </div>
            <div >
                上課地點<input type="text" id="classroom" name="classroom" />
            </div>
            <div >
                <button type="submit" >保&nbsp;&nbsp;&nbsp;存</button>
            </div>
        </form>
    </div>
    <script type="text/javascript">
        function check() {
            var name = document.getElementById("name");;
            var teacher = document.getElementById("teacher");
            var classroom = document.getElementById("classroom");
            
            //非空
            if(name.value == '') {
                alert('課程名稱為空');
                name.focus();
                return false;
            }
            if(teacher.value == '') {
                alert('教師為空');
                teacher.focus();
                return false;
            }
            if(classroom.value == '') {
                alert('上課地點為空');
                classroom.focus();
                return false;
            }
        
        }
    </script>
</body>
</html>

list.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
<style>
    .tb, td {
        border: 1px solid black;
        font-size: 22px;
    }
</style>
</head>
<body>
<%
         Object message = request.getAttribute("message");
         if(message!=null && !"".equals(message)){
     
    %>
         <script type="text/javascript">
              alert("<%=request.getAttribute("message")%>");
         </script>
    <%} %>
    <div align="center">
        <h1 style="color: red;">課程信息列表</h1>
        <a href="index.jsp">返回主頁</a>
        <table class="tb">
            <tr>
                <td>課程名稱</td>
                <td>任課教師</td>
                <td>上課地點</td>
                <td align="center" colspan="2">操作</td>
            </tr>
            <c:forEach items="${courses}" var="item">
                <tr>
                    <td>${item.name}</td>
                    <td>${item.teacher}</td>
                    <td>${item.classroom}</td>
                    <td><a href="courseServlet?method=getCoursebyName2&name=${item.name}">修改</a></td>
                </tr>
            </c:forEach>
        </table>
    </div>
</body>
</html>

deletebyName.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>刪除</title>
</head>
<body>
<%
         Object message = request.getAttribute("message");
         if(message!=null && !"".equals(message)){
     
    %>
         <script type="text/javascript">
              alert("<%=request.getAttribute("message")%>");
         </script>
    <%} %>
    <div align="center">
        <h1 style="color: red;">課程信息刪除</h1>
        <a href="index.jsp">返回主頁</a>
        <form action="courseServlet?method=getCoursebyName" method="post" onsubmit="return check()">
            <div >
                課程名稱<input type="text" id="name" name="name"/>
            </div>
            <div >
                <button type="submit" class="b">查&nbsp;&nbsp;&nbsp;找</button>
            </div>
        </form>
    </div>
    <script type="text/javascript">
        function check() {
            var name = document.getElementById("name");;
            
            //非空
            if(name.value == '') {
                alert('課程名稱為空');
                name.focus();
                return false;
            }
        }
    </script>
</body>
</html>

delete.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<style>
 .tb, td {
  border: 1px solid black;
  font-size: 22px;
 }
</style>
</head>
<body>
<div align="center">
        <h1 style="color: red;">課程信息刪除</h1>
        <a href="index.jsp">返回主頁</a>
        <table class="tb">
            <tr>
                <td>課程名稱</td>
                <td>${course.name}</td>
            </tr>
            <tr>
                <td>任課教師</td>
                <td>${course.teacher}</td>
            </tr>
            <tr>
                <td>上課地點</td>
                <td>${course.classroom}</td>
            </tr>
        </table>
        <div class="a">
            <a onclick="return check()" href="courseServlet?method=delete&name=${course.name}">刪&nbsp;&nbsp;&nbsp;除</a>
        </div>
    </div>
    <script type="text/javascript">
        function check() {
            if (confirm("真的要刪除嗎？")){
                return true;
            }else{
                return false;
            }
        }
    </script>
</body>
</html>

select.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<div align="center">
        <h1 style="color: red;">課程信息查詢</h1>
        <a href="index.jsp">返回主頁</a>
        <form action="courseServlet?method=select" method="post" onsubmit="return check()">
            <div >
                課程名稱<input type="text" id="name" name="name"/>
            </div>
            <div >
                任課教師<input type="text" id="teacher" name="teacher" />
            </div>
            <div >
                上課地點<input type="text" id="classroom" name="classroom" />
            </div>
            <div >
                <button type="submit" class="b">查&nbsp;&nbsp;&nbsp;詢</button>
            </div>
        </form>
    </div>
    <script type="text/javascript">
        function check() {
            var name = document.getElementById("name");;
            var teacher = document.getElementById("teacher");
            var classroom = document.getElementById("classroom");
            
            //非空
            if(name.value == '' && teacher.value == '' && classroom.value == '') {
                alert('請填寫一個條件');
                return false;
            }
        }
    </script>
</body>
</html>

selectlist.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
<style>
 .tb, td {
  border: 1px solid black;
  font-size: 22px;
 }
</style>
</head>
<body>
<div align="center">
        <h1 style="color: red;">課程信息列表</h1>
        <a href="index.jsp">返回主頁</a>
        <table class="tb">
            <tr>
                <td>課程名稱</td>
                <td>任課教師</td>
                <td>上課地點</td>
            </tr>
            <!-- forEach遍歷出adminBeans -->
             <c:forEach items="${courses}" var="item">
                <tr>
                    <td>${item.name}</td>
                    <td>${item.teacher}</td>
                    <td>${item.classroom}</td>
                </tr>
            </c:forEach>
        </table>
    </div>
</body>
</html>

update.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<%
         Object message = request.getAttribute("message");
         if(message!=null && !"".equals(message)){
     
    %>
         <script type="text/javascript">
              alert("<%=request.getAttribute("message")%>");
         </script>
    <%} %>
    <div align="center">
        <h1 style="color: red;">課程信息修改</h1>
        <a href="index.jsp">返回主頁</a>
        <form action="courseServlet?method=update&name=${course.name}" method="post" onsubmit="return check()">
            <div >
                課程名稱<input type="text" id="name" name="name" disabled value="${course.name}"/>
            </div>
            <div >
                任課教師<input type="text" id="teacher" name="teacher" value="${course.teacher}"/>
            </div>
            <div >
                上課地點<input type="text" id="classroom" name="classroom" value="${course.classroom}"/>               
            </div>
            <button type="submit">修&nbsp;&nbsp;&nbsp;改</button>
        </form>
    </div>
    <script type="text/javascript">
        function check() {
            var name = document.getElementById("name");
            var teacher = document.getElementById("teacher");
            var classroom = document.getElementById("classroom");
            
            //非空
            if(teacher.value == '') {
                alert('教師為空');
                teacher.focus();
                return false;
            }
            if(classroom.value == '') {
                alert('上課地點為空');
                classroom.focus();
                return false;
            }
       
        }
    </script>
</body>
</html>

注意：WebContent/WEN-INF/lib包下需要放置jstl.jar包和standard.jar包。可自行去網上下載。

免責聲明！

本站轉載的文章為個人學習借鑒使用，本站對版權不負任何法律責任。如果侵犯了您的隱私權益，請聯系本站郵箱yoyou2525@163.com刪除。

猜您在找 新手如何學習數據庫？？ Java web后台插入數據庫中文亂碼問題解決網站后台數據庫被手動修改后前端頁面不更新的問題解決學web前端開發寫給新手的建議，超實用！關於SyncNavigator數據庫實時同步軟件新手使用教程【推薦閱讀】 Html網頁鏈接數據庫驗證賬戶密碼（新手） Java Web連接各種數據庫方式匯總 java web連接數據庫簡單登錄初次Java web項目的建立以及與數據庫的連接 12-9java web 數據庫增刪改查