JavaWeb實現學生信息管理系統（2）

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本文接著上一篇，繼續為大傢分享瞭JavaWeb實現學生信息管理系統的第二篇，供大傢參考，具體內容如下

今日任務：實現學生管理系統的查找和添加功能！

一、查詢學生信息

1. index.jsp

先寫一個JSP頁面【WebContent/index.jsp】，裡面放一個超鏈接

<a href="StudentListServlet" rel="external nofollow" >顯示所有學生列表</a>

2. StudentListServlet.java

寫StudentListServlet【com.servlet包下的StudentListServlet.java】，接受請求，去調用service，再由service調用dao

package com.servlet;

import java.io.IOException;
import java.sql.SQLException;
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 com.domain.Student;
import com.service.StudentService;
import com.service.impl.StudentServiceImpl;

/**
 * 
 * 負責查詢所有的學生信息，然後呈現到list.jsp頁面上
 *
 */
@WebServlet("/StudentListServlet")
public class StudentListServlet extends HttpServlet {
 
 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  
  
  try {
   //1.查詢出來所有的學生
   StudentService service = new StudentServiceImpl();
   List<Student> list = service.findAll();
   
   //2.先把數據存儲到作用域中 
   //3..跳轉頁面
   
  } catch (SQLException e) {
  
   e.printStackTrace();
  }
  
 }

 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  doGet(request, response);
 }

}

3. StudentDao.java & StudentDaoImpl.java

3.1 StudentDao.java【com.dao包下】

package com.dao;

import java.sql.SQLException;
import java.util.List;

import com.domain.Student;

/**
 * 這是針對學生表的數據訪問
 * @author Administrator
 *
 */
public interface StudentDao {
 /**
  * 查詢所有學生
  * @return  List<Student>
  */
 List<Student> findAll() throws SQLException;
}

3.2 StudentDaoImpl.java【com.dao.impl包下】

實現StudentDao裡的findAll()方法。

public class StudentDaoImpl implements StudentDao {
 /**
  * 查詢所有學生
  * @throws SQLException 
  */
 @Override
 public List<Student> findAll() throws SQLException {
  
  QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());
  String sql = "select * from stu";
  List<Student> list = runner.query(sql, new BeanListHandler<Student>(Student.class));
  return list;
 }
}

4. StudentService.java 和 StudentService.java

4.1 StudentService.java

代碼同StudentDao.java,

public interface StudentService {

 /**
  * 查詢所有學生
  * @return   List<Student>
  * 
  */
 List<Student> findAll() throws SQLException;

}

4.2 StudentService.java

public class StudentServiceImpl implements StudentService{

 @Override
 public List<Student> findAll() throws SQLException {
  StudentDao dao = new StudentDaoImpl();
  return dao.findAll();
 } 
}

5. 在StudentListServlet存儲數據，並作出頁面響應

//2.先把數據存儲到作用域中
request.setAttribute("list", list);
   
//3..跳轉頁面
request.getRequestDispatcher("list.jsp").forward(request, response);

6. list.jsp

在list.jsp【WebContent/list.jsp】上顯示數據。

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>    
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>學生列表頁面 </title>
</head>
<body>
 <table border="1" width="700">
  
  <tr>
   <td colspan="8">
    <a href="add.jsp" rel="external nofollow" >添加</a>
   </td>
  </tr>
  
  <tr align="center">
   <td>編號</td>
   <td>姓名</td>
   <td>性別</td>
   <td>電話</td>
   <td>生日</td>
   <td>愛好</td>
   <td>簡介</td>
   <td>操作</td>
  </tr>
  
  <c:forEach items="${list }" var="stu">
   <tr align="center">
   <td>${stu.sid }</td>
   <td>${stu.sname }</td>
   <td>${stu.gender }</td>
   <td>${stu.phone }</td>
   <td>${stu.birthday }</td>
   <td>${stu.hobby }</td>
   <td>${stu.info }</td>
   <td><a href="#" rel="external nofollow"  rel="external nofollow" >更新</a>  <a href="#" rel="external nofollow"  rel="external nofollow" >刪除</a></td>
  </tr>
  </c:forEach>
  
 </table>
</body>
</html>

7. 查找結果如下：

二、添加學生信息

1. add.jsp

我們需要先跳轉到增加頁面，編寫增加頁面add.jsp【WebContent/add.jsp】

<body>

 <h3>添加學生頁面</h3>
 
 <form action="AddServlet" method="post">
  <table border="1" width="600">
   <tr>
    <td>姓名</td>
    <td><input type="text" name="sname"></td>
   </tr>
   <tr>
    <td>性別</td>
    <td>
     <input type="radio" name="gender" value="男">男
     <input type="radio" name="gender" value="女">女
    </td>
   </tr>
   <tr>
    <td>電話</td>
    <td><input type="text" name="phone"></td>
   </tr>
   <tr>
    <td>生日</td>
    <td><input type="text" name="birthday"></td>
   </tr>
   <tr>
    <td>愛好</td>
    <td>
     <input type="checkbox" name="hobby" value="遊泳">遊泳
     <input type="checkbox" name="hobby" value="籃球">籃球
     <input type="checkbox" name="hobby" value="足球">足球
     <input type="checkbox" name="hobby" value="看書">看書
     <input type="checkbox" name="hobby" value="寫字">寫字
    </td>
   </tr>
   <tr>
    <td>簡介</td>
    <td>
     <textarea rows="3" cols="20" name="info"></textarea>
    </td>
   </tr>
   <tr>
    <td colspan="2"><input type="submit" value="添加"></td>
   </tr>
  </table>
 </form>
 
</body>

實現結果如下：

2. AddServlet.java

點擊添加，提交數據到AddServlet，處理數據。
【備：com.servlet包下的AddServlet.java】

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  
  request.setCharacterEncoding("utf-8");
  
  try {

   //1.獲取客戶端提交上來的數據
   String sname = request.getParameter("sname");
   String gender = request.getParameter("gender");
   String phone = request.getParameter("phone");
   String birthday = request.getParameter("birthday");  //傳過來是1989-10-18
   String info = request.getParameter("info");
    
   //String hobby = request.getParameter("hobby");
   String [] h = request.getParameterValues("hobby");
   //[籃球，足球，寫字]-----籃球，足球，寫字
   String hobby = Arrays.toString(h);
   hobby = hobby.substring(1,hobby.length()-1);
   
   //2.添加到數據庫
   
   //String-------Date
   Date date = new SimpleDateFormat("yyyy-MM-dd").parse(birthday);
   
   Student student = new Student(sname,gender,phone,hobby,info,date);
   StudentService service = new StudentServiceImpl();
   service.insert(student);
   
   //3.跳轉到列表頁
   //這裡是直接跳轉到頁面上，那麼這個頁面會重新翻譯一次，上面那個request裡面的數據就沒有瞭
   //request.getRequestDispatcher("list.jsp").forward(request, response);
   
   //servlet除瞭能跳jsp之外，還能跳servlet
   request.getRequestDispatcher("StudentListServlet").forward(request, response);
   
   
  } catch (Exception e) {
   e.printStackTrace();
  }
   
 }

3. StudentDao & StudentService

 /**
  * 添加學生
  * @param student  需要添加到數據庫的學生對象
  * @throws SQLException
  */
 void insert(Student student) throws SQLException;

4. Dao & Service的實現

4.1 StudentDaoImpl.java

 @Override
 public void insert(Student student) throws SQLException {
  
  QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());
  String sql = "insert into stu values(null,?,?,?,?,?,?)";
  runner.update(sql,
    student.getSname(),
    student.getGender(),
    student.getPhone(),
    student.getBirthday(),
    student.getHobby(),
    student.getInfo()
    
    );
 }

4.2 StudentServiceImpl.java

@Override
 public void insert(Student student) throws SQLException {
  StudentDao dao = new StudentDaoImpl();
  dao.insert(student);
  
 }

5. 註意

完成瞭上述存儲工作之後，需要跳轉到列表頁面，這裡不能直接跳轉到列表頁面，否則沒有什麼內容顯示。應該先跳轉到查詢所有學生信息的那個servlet，即StudentListServlet，再由這個servlet跳轉到列表頁面。

request.getRequestDispatcher("StudentListServlet").forward(request, response);

hobby的value有多個值。處理時需多次轉化：

//String hobby = request.getParameter("hobby");
String [] h = request.getParameterValues("hobby");
//[籃球，足球，寫字]-----籃球，足球，寫字
String hobby = Arrays.toString(h);
hobby = hobby.substring(1,hobby.length()-1);

6. 添加結果如下：

以上就是本文的全部內容，希望對大傢的學習有所幫助，也希望大傢多多支持WalkonNet。

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