JavaWeb 增删改查功能

1.今天来写一个简单的增删改查功能，这个项目还是接着在昨天写的 --JavaWeb实现简单登录注册-- 来写的。

登录成功进来后对学生信息的增删改查

2.项目文件为：

3.好了，直接贴上今天新写的代码，昨天的代码就不重复贴了。

src文件下的代码：

controller：

 package com.maike.controller;

 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 com.maike.model.Student;

 import com.maike.model.StudentDto;

 import com.maike.service.UserService;

 import com.maike.service.UserServiceImpl;

 /**

  * Servlet implementation class AddStuServlet

  */

 @WebServlet("/AddStuServlet")

 public class AddStuServlet extends HttpServlet {

     UserService userService = new UserServiceImpl();

     private static final long serialVersionUID = 1L;

     /**

      * @see HttpServlet#HttpServlet()

      */

     public AddStuServlet() {

         super();

         // TODO Auto-generated constructor stub

     }

     /**

      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         response.getWriter().append("Served at: ").append(request.getContextPath());

     }

     /**

      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         String stuName = request.getParameter("stuName");

         String stuSex = request.getParameter("stuSex");

         String stuAge = request.getParameter("stuAge");

         String stuClass = request.getParameter("stuClass");

         StudentDto studentDto = new StudentDto();

         studentDto.setStuName(stuName);

         studentDto.setStuSex(stuSex);

         studentDto.setStuAge(stuAge);

         studentDto.setStuClass(stuClass);

         int k = userService.addStu(studentDto);

         if(k > 0) {

             List<Student> list = userService.seleStuAll();

             request.setAttribute("stuList", list);

             request.getRequestDispatcher("showStu.jsp").forward(request, response);

         }else {

             response.getWriter().append("添加失败").append(request.getContextPath());

             request.getRequestDispatcher("addStu.jsp").forward(request, response);

         }

     }

 }

AddStuServlet

 package com.maike.controller;

 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 com.maike.model.Student;

 import com.maike.service.UserService;

 import com.maike.service.UserServiceImpl;

 /**

  * Servlet implementation class DeleteStuServlet

  */

 @WebServlet("/DeleteStuServlet")

 public class DeleteStuServlet extends HttpServlet {

     UserService userService = new UserServiceImpl();

     private static final long serialVersionUID = 1L;

     /**

      * @see HttpServlet#HttpServlet()

      */

     public DeleteStuServlet() {

         super();

         // TODO Auto-generated constructor stub

     }

     /**

      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         String stuName = request.getParameter("stuName");

         int  k = userService.deleteStu(stuName);

         List<Student> list = userService.seleStuAll();

         request.setAttribute("stuList", list);

         request.getRequestDispatcher("showStu.jsp").forward(request, response);

     }

     /**

      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         doGet(request, response);

     }

 }

DeleteStuServlet

 package com.maike.controller;

 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;

 /**

  * Servlet implementation class ToAddStuServlet

  */

 @WebServlet("/ToAddStuServlet")

 public class ToAddStuServlet extends HttpServlet {

     private static final long serialVersionUID = 1L;

     /**

      * @see HttpServlet#HttpServlet()

      */

     public ToAddStuServlet() {

         super();

         // TODO Auto-generated constructor stub

     }

     /**

      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         request.getRequestDispatcher("addStu.jsp").forward(request, response);

     }

     /**

      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         doGet(request, response);

     }

 }

ToAddStuServlet

 package com.maike.controller;

 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.maike.model.Student;

 import com.maike.service.UserService;

 import com.maike.service.UserServiceImpl;

 /**

  * Servlet implementation class ToUpdateStuServlet

  */

 @WebServlet("/ToUpdateStuServlet")

 public class ToUpdateStuServlet extends HttpServlet {

     UserService userService = new UserServiceImpl();

     private static final long serialVersionUID = 1L;

     /**

      * @see HttpServlet#HttpServlet()

      */

     public ToUpdateStuServlet() {

         super();

         // TODO Auto-generated constructor stub

     }

     /**

      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         String stuName = request.getParameter("stuName");

         Student student = userService.getStuByName(stuName);

         request.setAttribute("student", student);

         request.getRequestDispatcher("updateStu.jsp").forward(request, response);

     }

     /**

      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         doGet(request, response);

     }

 }

ToUpdateStuServlet

 package com.maike.controller;

 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 com.maike.model.Student;

 import com.maike.service.UserService;

 import com.maike.service.UserServiceImpl;

 /**

  * Servlet implementation class UpdateStuServlet

  */

 @WebServlet("/UpdateStuServlet")

 public class UpdateStuServlet extends HttpServlet {

     UserService userService = new UserServiceImpl();

     private static final long serialVersionUID = 1L;

     /**

      * @see HttpServlet#HttpServlet()

      */

     public UpdateStuServlet() {

         super();

         // TODO Auto-generated constructor stub

     }

     /**

      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         response.getWriter().append("Served at: ").append(request.getContextPath());

     }

     /**

      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

      */

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

         // TODO Auto-generated method stub

         request.setCharacterEncoding("utf-8");

         String stuName = request.getParameter("stuName");

         String stuSex = request.getParameter("stuSex");

         String stuClass = request.getParameter("stuClass");

         Student student = new Student();

         student.setStuName(stuName);

         student.setStuSex(stuSex);

         student.setStuClass(stuClass);

         int k = userService.updateStu(student);

         List<Student> list = userService.seleStuAll();

         request.setAttribute("stuList", list);

         request.getRequestDispatcher("showStu.jsp").forward(request, response);

     }

 }

UpdateStuServlet

dao:

 package com.maike.dao;

 import java.util.List;

 import com.maike.model.Student;

 public interface StudentDao {

     List<Student> selectAll();

     Student selectByName(String stuName);

     int insert(Student student);

     int update(Student student);

     int delete(String stuName);

 }

StudentDao

 package com.maike.dao;

 import java.sql.Connection;

 import java.sql.PreparedStatement;

 import java.sql.ResultSet;

 import java.sql.SQLException;

 import java.util.ArrayList;

 import java.util.List;

 import com.maike.model.Student;

 import com.maike.util.ConnectionUtil;

 public class StudentDaoImpl implements StudentDao {

     Student student;

     Connection con = null;

     PreparedStatement pt = null;

     ResultSet rs = null;

     String sql;

     /**

      * 查询所有学生

      */

     @Override

     public List<Student> selectAll() {

         // TODO Auto-generated method stub

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

         sql = "select * from student";

         try {

             con = ConnectionUtil.getConnection();

             pt = con.prepareStatement(sql);

             rs = pt.executeQuery();

             while(rs.next()) {

                 student = new Student();

                 student.setStuId(rs.getInt("stu_id"));

                 student.setStuName(rs.getString("stu_name"));

                 student.setStuSex(rs.getString("stu_sex"));

                 student.setStuAge(rs.getInt("stu_age"));

                 student.setStuClass(rs.getString("stu_class"));

                 list.add(student);

             }

         } catch (SQLException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }finally {

             ConnectionUtil.closeRe(con, pt, rs);

         }

         return list;

     }

     /**

      * 通过名字查询学生

      */

     @Override

     public Student selectByName(String stuName) {

         // TODO Auto-generated method stub

         sql = "select * from student where stu_name = ?";

         try {

             con = ConnectionUtil.getConnection();

             pt = con.prepareStatement(sql);

             pt.setString(1, stuName);

             rs = pt.executeQuery();

             while(rs.next()) {

                 student = new Student();

                 student.setStuId(rs.getInt("stu_id"));

                 student.setStuName(rs.getString("stu_name"));

                 student.setStuSex(rs.getString("stu_sex"));

                 student.setStuAge(rs.getInt("stu_age"));

                 student.setStuClass(rs.getString("stu_class"));

             }

         } catch (SQLException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }finally {

             ConnectionUtil.closeRe(con, pt, rs);

         }

         return student;

     }

     /**

      * 添加学生

      */

     @Override

     public int insert(Student student) {

         // TODO Auto-generated method stub

         int k = 0;

         sql = "insert into student values(null,?,?,?,?)";

         try {

             con = ConnectionUtil.getConnection();

             pt = con.prepareStatement(sql);

             pt.setString(1, student.getStuName());

             pt.setString(2, student.getStuSex());

             pt.setInt(3, student.getStuAge());

             pt.setString(4, student.getStuClass());

             k = pt.executeUpdate();

         } catch (SQLException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }finally {

             ConnectionUtil.closeRe(con, pt);

         }

         return k;

     }

     /**

      * 更新学生

      */

     @Override

     public int update(Student student) {

         // TODO Auto-generated method stub

         int k = 0;

         sql = "update student set stu_sex = ? ,stu_class = ? where stu_name = ?";

         try {

             con = ConnectionUtil.getConnection();

             pt = con.prepareStatement(sql);

             pt.setString(1, student.getStuSex());

             pt.setString(2, student.getStuClass());

             pt.setString(3, student.getStuName());

             k = pt.executeUpdate();

         } catch (SQLException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }finally {

             ConnectionUtil.closeRe(con, pt);

         }

         return k;

     }

     /**

      * 通过名字删除学生

      */

     @Override

     public int delete(String stuName) {

         // TODO Auto-generated method stub

         int k = 0;

         sql = "delete from student where stu_name = ?";

         try {

             con = ConnectionUtil.getConnection();

             pt = con.prepareStatement(sql);

             pt.setString(1, stuName);

             k = pt.executeUpdate();

         } catch (SQLException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }finally {

             ConnectionUtil.closeRe(con, pt);

         }

         return k;

     }

 }

StudentDaoImpl

model:

 package com.maike.model;

 public class Student {

     private int stuId;

     private String stuName;

     private String stuSex;

     private int stuAge;

     private String stuClass;

     public int getStuId() {

         return stuId;

     }

     public void setStuId(int stuId) {

         this.stuId = stuId;

     }

     public String getStuName() {

         return stuName;

     }

     public void setStuName(String stuName) {

         this.stuName = stuName;

     }

     public String getStuSex() {

         return stuSex;

     }

     public void setStuSex(String stuSex) {

         this.stuSex = stuSex;

     }

     public int getStuAge() {

         return stuAge;

     }

     public void setStuAge(int stuAge) {

         this.stuAge = stuAge;

     }

     public String getStuClass() {

         return stuClass;

     }

     public void setStuClass(String stuClass) {

         this.stuClass = stuClass;

     }

     @Override

     public String toString() {

         return "Student [stuId=" + stuId + ", stuName=" + stuName + ", stuSex=" + stuSex + ", stuAge=" + stuAge

                 + ", stuClass=" + stuClass + "]";

     }

 }

Student

 package com.maike.model;

 public class StudentDto {

     private String stuId;

     private String stuName;

     private String stuSex;

     private String stuAge;

     private String stuClass;

     public String getStuId() {

         return stuId;

     }

     public void setStuId(String stuId) {

         this.stuId = stuId;

     }

     public String getStuName() {

         return stuName;

     }

     public void setStuName(String stuName) {

         this.stuName = stuName;

     }

     public String getStuSex() {

         return stuSex;

     }

     public void setStuSex(String stuSex) {

         this.stuSex = stuSex;

     }

     public String getStuAge() {

         return stuAge;

     }

     public void setStuAge(String stuAge) {

         this.stuAge = stuAge;

     }

     public String getStuClass() {

         return stuClass;

     }

     public void setStuClass(String stuClass) {

         this.stuClass = stuClass;

     }

     @Override

     public String toString() {

         return "StudentDto [stuId=" + stuId + ", stuName=" + stuName + ", stuSex=" + stuSex + ", stuAge=" + stuAge

                 + ", stuClass=" + stuClass + "]";

     }

 }

StudentDto

service:

 package com.maike.service;

 import java.util.List;

 import com.maike.model.Student;

 import com.maike.model.StudentDto;

 public interface UserService {

     int insertUser(String userName,String userPwd,String userRePwd);

     int judgeLogin(String userName,String userPwd);

     List<Student> seleStuAll();

     int addStu(StudentDto studentDto);

     int updateStu(Student student);

     int deleteStu(String stuName);

     Student getStuByName(String stuName);

 }

UserService

     /**

      * seleStuAll:查询所有学生信息. <br/>

      */

     @Override

     public List<Student> seleStuAll() {

         // TODO Auto-generated method stub

         return studentDao.selectAll();

     }

     /**

      * addStu:添加学生信息 .<br/>

      */

     @Override

     public int addStu(StudentDto studentDto) {

         // TODO Auto-generated method stub

         int k = 0;

         String stuName = studentDto.getStuName();

         String stuAge = studentDto.getStuAge();

         if(stuName == null || stuAge == null) {

             return k;

         }

         int IntAge = Integer.parseInt(stuAge);

         Student student = new Student();

         student.setStuName(stuName);

         student.setStuSex(studentDto.getStuSex());

         student.setStuAge(IntAge);

         student.setStuClass(studentDto.getStuClass());

         k = studentDao.insert(student);

         return k;

     }

     /**

      * updateStu:修改学生信息 .<br/>

      */

     @Override

     public int updateStu(Student student) {

         // TODO Auto-generated method stub

         return studentDao.update(student);

     }

     /**

      * deleteStu :删除学生信息 .<br/>

      */

     @Override

     public int deleteStu(String stuName) {

         // TODO Auto-generated method stub

         return studentDao.delete(stuName);

     }

     /**

      * 通过名字查询学生

      */

     @Override

     public Student getStuByName(String stuName) {

         // TODO Auto-generated method stub

         return studentDao.selectByName(stuName);

     }

UserServiceImpl

jsp页面：

 <%@ 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 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>学生信息</title>

 </head>

 <body>

   <br/>

   <br/>

   <br/>

   <h2 align = "center">学生信息列表</h2>

     <table align = "center" width="15%">

         <tr>

             <th align = "center"><a href = "ToAddStuServlet"><button style = "color:blue">添加学生</button></a></th>

         </tr>

     </table>

     <table align = "center">

         <tr>

             <th>姓名</th><th>性别</th><th>年龄</th><th>班级</th><th colspan="2">管理</th>

         </tr>

         <c:forEach var = "list" items="${stuList}">

         <tr>

             <td>${list.stuName }</td><td>${list.stuSex}</td><td>${list.stuAge }</td><td>${list.stuClass}</td>

             <td><a href = "DeleteStuServlet?stuName=${list.stuName }" ><button style = "color:blue">删除</button></a></td><td><a href = "ToUpdateStuServlet?stuName=${list.stuName }"><button style = "color:blue">修改</button></a></td>

         </tr>

         </c:forEach>

     </table>

 </body>

 </html>

showStu

 <%@ 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>添加页面</title>

 </head>

 <body>

 <br>

 <br>

 <br>

 <h2 align = "center">添加页面</h2>

     <form action="AddStuServlet" method = "post">

         <table align = "center">

             <tr>

                 <td>名字</td><td><input type = "text" name = "stuName" ></td>

             </tr>

             <tr>

                 <td>性别</td><td><input type = "text" name = "stuSex" ></td>

             </tr>

             <tr>

                 <td>年龄</td><td><input type = "text" name = "stuAge" placeholder ="请输入整数" ></td>

             </tr>

             <tr>

                 <td>班级</td><td><input type = "text" name = "stuClass" ></td>

             </tr>

             <tr>

                 <td colspan="2" align = "center"><input type="submit" value = "添加" style="color:blue" ></td>

             </tr>

         </table>

     </form>

 </body>

 </html>

addStu

 <%@ 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>修改页面</title>

 </head>

 <body>

 <br>

 <br>

 <br>

 <h2 align = "center">修改页面</h2>

     <form action="UpdateStuServlet" method = "post" align = "center">

         <table align = "center">

             <tr>

                 <td>名字</td><td><input type = "text" name = "stuName" value = "${student.stuName }" readonly="readonly" ></td>

             </tr>

             <tr>

                 <td>性别</td><td><input type = "text" name = "stuSex" value  = "${student.stuSex }"></td>

             </tr>

             <tr>

                 <td>年龄</td><td><input type = "text" name = "stuAge" value  = "${student.stuAge }" disabled="disabled"></td>

             </tr>

             <tr>

                 <td>班级</td><td><input type = "text" name = "stuClass" value  = "${student.stuClass }"></td>

             </tr>

             <tr>

                 <td colspan="2"><input type="submit" value = "修改" style="color:blue" ></td>

             </tr>

         </table>

     </form>

 </body>

 </html>

updateStu

数据库创建语句：

 CREATE TABLE nanfeng.student (

     stu_id INT NOT NULL AUTO_INCREMENT,

     stu_name varchar(100) NULL,

     stu_sex varchar(100) NULL,

     stu_age INT NULL,

     stu_class varchar(100) NULL,

     CONSTRAINT student_pk PRIMARY KEY (stu_id)

 )

 ENGINE=InnoDB

 DEFAULT CHARSET=utf8

 COLLATE=utf8_general_ci;