JAVA--高级基础开发MVC_CRUD

MVC_CRUD:操做数据库实现增删改查√
import java.io.Serializable;
public class Student implements Serializable {
    private static final long serialVersionUID = 5289634478724041840L;
    private Integer stuId;
    private String  stuName;
    private Integer stuAge;
    private Integer stuXueli;
    private String  stuGender;
    private Double  stuScore;
    private String  stuDate;
    private String  stuHobby;
    private String  stuDes;
    public static long getSerialVersionUID() {
        return serialVersionUID;
    }
    public Integer getStuId() {
        return stuId;
    }
    public void setStuId(Integer stuId) {
        this.stuId = stuId;
    }
    public String getStuName() {
        return stuName;
    }
    public void setStuName(String stuName) {
        this.stuName = stuName;
    }
    public Integer getStuAge() {
        return stuAge;
    }
    public void setStuAge(Integer stuAge) {
        this.stuAge = stuAge;
    }
    public Integer getStuXueli() {
        return stuXueli;
    }
    public void setStuXueli(Integer stuXueli) {
        this.stuXueli = stuXueli;
    }
    public String getStuGender() {
        return stuGender;
    }
    public void setStuGender(String stuGender) {
        this.stuGender = stuGender;
    }
    public Double getStuScore() {
        return stuScore;
    }

    public void setStuScore(Double stuScore) {
        this.stuScore = stuScore;
    }
    public String getStuDate() {
        return stuDate;
    }
    public void setStuDate(String stuDate) {
        this.stuDate = stuDate;
    }
    public String getStuHobby() {
        return stuHobby;
    }
    public void setStuHobby(String stuHobby) {
        this.stuHobby = stuHobby;
    }
    public String getStuDes() {
        return stuDes;
    }
    public void setStuDes(String stuDes) {
        this.stuDes = stuDes;
    }
    @Override
    public String toString() {
        return "Student{" +
                "stuId=" + stuId +
                ", stuName='" + stuName + '\'' +
                ", stuAge=" + stuAge +
                ", stuXueli=" + stuXueli +
                ", stuGender='" + stuGender + '\'' +
                ", stuScore=" + stuScore +
                ", stuDate='" + stuDate + '\'' +
                ", stuHobby='" + stuHobby + '\'' +
                ", stuDes='" + stuDes + '\'' +
                '}';
    }
}
import com.Model.Student;
import java.util.List;
public interface IStudentDao {
    //添加的方法
    public  int  insert(Student student);
    //删除的方法
    public  int  delete(int  stuId);
    //修改的方法
    public int update(Student  student);
    //查询的方法，根据id去修改
    public Student  findFindy(int  stuId);
    //查询的方法：查询全部的信息
    public List<Student>  finaAll();

}
import com.Dao.IStudentDao;
import com.Model.Student;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import javax.sql.DataSource;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

//Dao接口的实现类
public class StudentDaoimp implements IStudentDao {
    //建立一个全局的QueryRunner 对象、 //方法一：
    private QueryRunner qr;

    //方法二：
    private DataSource  ds;
    public StudentDaoimp(DataSource   ds){
        qr=new QueryRunner(ds);
    }

    @Override
    public int insert(Student student) {
        String  sql="insert  into  student(stuName,stuAge,stuXueli,stuGender,stuScore,stuDate,stuHobby,stuDes)values(?,?,?,?,?,?,?,?)";
       Object[]prams={student.getStuName(),student.getStuAge(),student.getStuXueli(),student.getStuGender(),student.getStuScore(),student.getStuDate(),student.getStuHobby(),student.getStuDes()};
       int i=0;
       try{
           i=qr.update(sql,prams);
       }catch (SQLException  ce){
           ce.printStackTrace();
       }
       return i;
    }
   @Override
    public int delete(int stuId) {
                String  sql="delete   from student where stuId=?";
        Object[]prams={stuId};
        int i=0;
        try{
            i=qr.update(sql,prams);
        }catch (SQLException  ce){
            ce.printStackTrace();
        }
        return i;
    }
   @Override
    public int update(Student student) {
        String  sql="update  student  set stuName=?,stuAge=?,stuXueli=?,stuGender=?,stuScore=?,stuDate=?,stuHobby=?,stuDes=? where stuId=?";
        Object[]prams={student.getStuName(),student.getStuAge(),student.getStuXueli(),student.getStuGender(),student.getStuScore(),student.getStuDate(),student.getStuHobby(),student.getStuDes(),student.getStuId()};
        int i=0;
        try{
            i=qr.update(sql,prams);
        }catch (SQLException  ce){
            ce.printStackTrace();
        }
        return i;
    }
    @Override
    public Student findFindy(int stuId) {
        String  sql="select  *  from  student where stuId=?";
        Object[]prams={stuId};
        Student  student=null;
        try{
            student=qr.query(sql,new BeanHandler<Student>(Student.class),prams);
        }catch (SQLException  ce){
            ce.printStackTrace();
        }
        return student;
    }
    @Override
    public List<Student> finaAll(){
        String sql="select  *  from student";
        List<Student>list=new ArrayList<>();
        try{
            list=qr.query(sql,new BeanListHandler<Student>(Student.class));
        }catch (SQLException  ce){
            ce.printStackTrace();
        }
        return list;
     }
}
代理类
import com.Dao.IStudentDao;
import com.Dao.imp.StudentDaoimp;
import com.Model.Student;
import com.Utils.DatabaseConnection;
import javax.sql.DataSource;
import java.util.List;
public class StudentDaoProxy implements IStudentDao {
    private IStudentDao studentDao;
    private DataSource ds;
    public  StudentDaoProxy(){
        ds=DatabaseConnection.getDateSource();
        studentDao=new StudentDaoimp(ds);
    }
    @Override
    public int insert(Student student) {
        int i=studentDao.insert(student);
        return i;
    }
    @Override
    public int delete(int stuId){
        int i=studentDao.delete(stuId);
        return i;
    }
    @Override
    public int update(Student student) {
       int i=studentDao.update(student);
        return i;
    }
    @Override
    public Student findFindy(int stuId) {
        Student  student=studentDao.findFindy(stuId);
        return student;
    }
    @Override
    public List<Student> finaAll() {
       List<Student>list=studentDao.finaAll();
        return list;
    }

}

import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

/**
 * @PACKAGE_NAME: com.Model.utils
 * @ClASS_NAME: DaoFactory
 * @Description DAO工厂类
 * @Author: Model
 * @DATE: 2019/8/23 15:34
 * @Version : 1.0
 **/
public class Daofactory { 
    private static Properties p;
    //map集合用来充当缓存，key要和dao.properties中的key一致
    //值，DAO接口的实例对象
    private static Map<String,Object> cache;

    //初始化
    static{
        p=new Properties();
        cache=new HashMap<>();
        //加载dao.properties属性文件
        InputStream is=Thread.currentThread().getContextClassLoader().getResourceAsStream("dao.properties");
        try {
            p.load(is);
        }catch (IOException ce){
            ce.printStackTrace();
        }
    }

   /**
     * 线程安全的泛型方法
     * @param daoName  就是dao.properties属性文件中key的名字
     * @param daoClass 就是key所对应值得父接口或者接口的实现类
     * @param <T>
     * @return
     */
    public synchronized static<T> T getInstance(String daoName,Class daoClass){
        //先从map集合中，根据KEY去查找，有没有对应的值
        T t=(T)cache.get(daoName);
        if(t==null){//说明map集合中不存在当前daoName锁对应的键值对
            //去属性文件中查找指定KEY是否存在，若是存在，则获取key所对应的值
            //值就是某个DAO接口的实现类的全限定名
            String className=p.getProperty(daoName);
           if(null!=className&&!"".equals(className)){//说明key-value存在
                try {
                    //把指定类的字节码文件加载JVM虚拟机中
                    Class clazz = Class.forName(className);
                    //经过反射机制调用类中无参数的构造方法建立clazz的对象
                    t=(T)daoClass.cast(clazz.getDeclaredConstructor().newInstance());
                    //把对象添加到map集合中
                    cache.put(daoName,t);
                }catch (Exception ce){
                    ce.printStackTrace();
                }
            }
        }
        return t;
    }

}
import com.alibaba.druid.pool.DruidDataSource;
import javax.sql.DataSource;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

//专门负责数据库打开与关闭操做的类
public class DatabaseConnection {
    //建立阿里巴巴链接池对象
    private  static DruidDataSource ds;
    private  static Properties P;
    static {
        ds=new DruidDataSource();
        P=new Properties();
        //读取属性文件
        InputStream input=Thread.currentThread().getContextClassLoader().getResourceAsStream("druid.properties");
        //加载P对象
        try{
            P.load(input);
        }catch(IOException ce){
            ce.printStackTrace();
        }
        //根据键获取值
        ds.setDriverClassName(P.getProperty("driverClass"));
        ds.setUrl(P.getProperty("url"));
        ds.setUsername(P.getProperty("user"));
        ds.setPassword(P.getProperty("password"));
        //配链接池的参数
        ds.setInitialSize(Integer.parseInt(P.getProperty("initialSize")));
        ds.setMinIdle(Integer.parseInt(P.getProperty("minIdle")));
        ds.setMaxActive(Integer.parseInt(P.getProperty("maxActive")));
        ds.setMaxWait(Integer.parseInt(P.getProperty("maxWait")));
        ds.setTimeBetweenEvictionRunsMillis(Integer.parseInt(P.getProperty("timeBetweenEvictionRunsMillis")));
    }
    public  static DataSource getDateSource(){
        return ds;
    }
    //获取数据库链接对象
    public  static Connection getConnection()throws SQLException {
        return ds.getConnection();
    }


    //关闭数据库链接对象之insert  delete update的操做
    public static  void  close(Connection  con, Statement state)throws SQLException{
        con.close();;
        state.close();
    }
    //关闭数据库链接的对象之 select 查找查询的操做
    public static  void close(Connection  con, Statement  state, ResultSet set)throws SQLException{
        set.close();
        state.close();
        con.close();
    }
    //关闭获取数据库链接对象
    public  static  void  close(Connection  con)throws SQLException{
        con.close();
    }
    // 关闭执行Statement执行SQL 语句的对象
    public static  void close(Statement  state)throws SQLException{
        state.close();
    }
    //关闭结果集对象ResultSet对象
    public static  void close(ResultSet  set)throws SQLException{
        set.close();
    }
}
import com.Dao.IStudentDao;
import com.Factory.Daofactory;
import com.Model.Student;
import java.util.List;

//业务层
//Daofactory：的做用是专门用来建立dao接口的实现类对象的。
public class StudentService {
    private IStudentDao studentDao= Daofactory.getInstance("UserDao",IStudentDao.class);
    //添加的方法：
    public int  insert(Student student){
        return studentDao.insert(student);
    }
    //删除的方法;
    public int  delete(int stuId){
        return studentDao.delete(stuId);
    }
    //修改的方法：
    public int  update(Student  student){
        return  studentDao.update(student);
    }
    //查询的方法：
    public Student  findFindy(int  stuId){
        return studentDao.findFindy(stuId);
    }
    //查询全部的方法：
    public List<Student> findAll(){
        return studentDao.finaAll();
    }
}
服务器端：：
import com.Model.Student;
import com.Service.StudentService;
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.IOException;
import java.io.PrintWriter;
import java.util.List;

@WebServlet("/mvc")
public class MVC_Servlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doPost(req, resp);
    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //设置请求的编码
        req.setCharacterEncoding("UTF-8");
        String  method=req.getParameter("method");
        if(null!=method&&!"".equals(method)){
            if("stuAdd".equals(method)){ //调用添加的方法
                addStu(req, resp);
            }else if("list".equals(method)){//查询的方法
                addList(req, resp);
            }else if("update".equals(method)){//修改的方法
                stuaUpdate(req, resp);
            }else if("delete".equals(method)){//删除的方法
                studelete(req, resp);
            }else if("edit".equals(method)){//编辑的方法
                stuedit(req,resp);
            }
        }
    }
      //学员信息添加的方法
    protected void addStu(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        //获取请求的参数
        String  stuName=req.getParameter("stuName");
        String  stuAge=req.getParameter("stuAge");
        String  stuXueli=req.getParameter("stuXueli");
        String  stuGender=req.getParameter("stuGender");
        String  stuScore=req.getParameter("stuScore");
        String  stuDate=req.getParameter("stuDate");
        String[]stuHobby=req.getParameterValues("stuHobby");
        String stuDes=req.getParameter("stuDes");

        //准备一个Student对象。获得属性的值
        Student student=new Student();
        student.setStuName(stuName);
        student.setStuAge(Integer.parseInt(stuAge));
        student.setStuXueli(Integer.parseInt(stuXueli));
        student.setStuGender(stuGender);
        student.setStuScore(Double.parseDouble(stuScore));
        student.setStuDate(stuDate);
        StringBuilder  stringBuilder=new StringBuilder();
        for(String ss:stuHobby){
            stringBuilder.append(ss);
            stringBuilder.append("-");
        }
        student.setStuHobby(stringBuilder.toString());
        student.setStuDes(stuDes);

        //建立业务层的对象
        StudentService services=new StudentService();
        //添加业务层的对象
        int  i=services.insert(student);
        //设置响应的内容的类型
        resp.setContentType("text/html;charset=UTF-8");
        //获取字符输出流
        PrintWriter out=resp.getWriter();
        if(i>0){
            req.setAttribute("MSG","学员的信息添加成功");
        }else{
            req.setAttribute("MSG","学员的信息添加失败");
        }
        //请求分派到成功的页面
        req.getRequestDispatcher("success.jsp").forward(req,resp);
    }
     //学员信息的查询页面
    protected void addList(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //建立业务层的对象

        StudentService  studentService=new StudentService();
        //建立业务层对象添加到list集合中
        List<Student>list=studentService.findAll();

        //把list集合添加到请求域中
        req.setAttribute("List",list);
        //把List集合请求分派到查询成功的页面
        req.getRequestDispatcher("list.jsp").forward(req,resp);

    }
    //学员信息编辑的方法
    protected void  stuedit(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //或取请求的参数，根据id去编辑
        String  stuId=req.getParameter("stuId");
        //建立业务层的对象
        StudentService studentService=new StudentService();
        Student  student=studentService.findFindy(Integer.parseInt(stuId));

        //把Student对象添加到请求域中
        req.setAttribute("student",student);
        //请求分派到成功的页面
        req.getRequestDispatcher("edit.jsp").forward(req,resp);
    }
    //学员信息修改的方法
    protected void stuaUpdate(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        //设置请求中的编码
        req.setCharacterEncoding("UTF-8");
        //根据id去修改，获取请求中的参数
        String stuId=req.getParameter("stuId");
        String stuName=req.getParameter("stuName");
        String stuAge=req.getParameter("stuAge");
        String stuXueli=req.getParameter("stuXueli");
        String stuGender=req.getParameter("stuGender");
        String stuScore=req.getParameter("stuScore");
        String stuDate=req.getParameter("stuDate");
        String[]hobbys=req.getParameterValues("stuHobby");
        String stuDes=req.getParameter("stuDes");

        //建立业务层的对象。根据id去修改，返回的是一个Student对象
        StudentService  studentService=new StudentService();
        Student  student=studentService.findFindy(Integer.parseInt(stuId));
        student.setStuName(stuName);
        student.setStuAge(Integer.parseInt(stuAge));
        student.setStuXueli(Integer.parseInt(stuXueli));
        student.setStuGender(stuGender);
        student.setStuScore(Double.parseDouble(stuScore));
        student.setStuDate(stuDate);
        //爱好为数组，必须用字符输出流来输出
        StringBuilder  builder=new StringBuilder();
        for(String  ss:hobbys){
            builder.append(ss);
            builder.append("-");
        }
        student.setStuHobby(builder.toString());
        student.setStuDes(stuDes);
        int i=studentService.update(student);
        if(i>0){
            req.setAttribute("MSG","学员的信息修改为功");
        }else{
            req.setAttribute("MSG","学员的信息修改失败");
        }
        //请求分派到成功的页面
        req.getRequestDispatcher("success.jsp").forward(req,resp);
    }
    //学员信息删除的方法
    protected void studelete(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取请求中的参数
        String stuId=req.getParameter("stuId");
        //建立业务层的对象
        StudentService studentService=new StudentService();
        int i=studentService.delete(Integer.parseInt(stuId));
       if(i>0){
           req.setAttribute("MSG","学员的信息删除成功");
       }else{
           req.setAttribute("MSG","学员的信息删除失败");
       }
       req.getRequestDispatcher("success.jsp").forward(req,resp);
    }
}
JSP前端的页面:添加的页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>学员信息的添加页面</title>
</head>
<body>
<h2 style="color: red" align="center">学员信息的添加页面</h2>
<form  action="mvc?method=stuAdd" method="post" class="form" onsubmit=" return lwj();">
    <table>
        <tr>
            <td>用户名:</td>
            <td>
                <input type="text" name="stuName" id="stuName" style="background: aqua" placeholder="请输入用户名"></br>
            </td>
        </tr>
        <tr>
            <td>年龄:</td>
            <td>
                <input type="text" name="stuAge" id="stuAge" style="background: aqua" placeholder="请输入年龄"></br>
            </td>
        </tr>
        <tr>
            <td>学@历:</td>
            <td>
                <select name="stuXueli" id="stuXueli">
                    <option value="0">小学</option>
                    <option value="1">初中</option>
                    <option value="2">高中</option>
                    <option value="3">大学</option>
                </select>
            </td>
        </tr><br>
        <tr>
            <td>性  别:</td>
            <td>
                <input type="radio" name="stuGender" value="女">女
                <input type="radio" name="stuGender" value="男">男</br>
            </td>
        <tr>
            <td>成@绩:</td>
            <td>
                <input type="text" name="stuScore" id="stuScore" style="background: aqua" placeholder="请输入成绩"><br>
            </td>
        </tr>
        <tr>
            <td>生  日:</td>
            <td>
                <input type="date" name="stuDate" id="stuDate"></br>
            </td>
        </tr>
        <tr>
            <td>爱@好:</td>
            <td>
                <input type="checkbox" name="stuHobby" value="play">篮球
                <input type="checkbox" name="stuHobby" value="sing">唱歌
                <input type="checkbox" name="stuHobby" value="sleep">睡觉
            </td><br>
        </tr>
        <tr>
            <td>文本框:</td>
            <td>
                <textarea cols="30" rows="20" name="stuDes" style="background: salmon"></textarea>
            </td>
        </tr>
        <tr>
            <td colspan="2" align="center">
                <input type="submit" value="提交">
                <input type="reset"  value="重置">
            </td>
        </tr>
    </table>
</form>
</body>
</html>
<script src="js/from.js"></script>

JSP前端的页面:查询的页面
<%@ page import="java.util.List" %>
<%@ page import="com.Model.Student" %><%--
  Created by IntelliJ IDEA.
  User: Lenovo-T410
  Date: 2019/12/12
  Time: 11:41
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>列表的显示页面</title>
</head>
<body>
<h2 style="color: red">学员信息的查询页面</h2>

<table width="100%" border="100%" style="background: blanchedalmond">
    <tr>
        <th>ID</th>
        <th>姓名</th>
        <th>年龄</th>
        <th>学历</th>
        <th>性别</th>
        <th>成绩</th>
        <th>生日</th>
        <th>爱好</th>
        <th>简介</th>
        <th>操做</th>
    </tr>
    <%--获取Servlet请求域中的数据--%>
    <%
     List<Student>list=(List<Student>)request.getAttribute("List");
     //作个验证，为了防止list集合报空指针异常，若是==0就等于0，不然返回他自己
     int size=list.size()==0?0:list.size();
      for(int i=0;i<size;i++){
          Student  student=list.get(i);%>
    <tr align="center">
        <td>
            <%=student.getStuId()%>
        </td>
        <td>
            <%=student.getStuName()%>
        </td>
        <td>
            <%=student.getStuAge()%>
        </td>
        <td>
            <%=student.getStuXueli()%>
        </td>
        <td>
            <%=student.getStuGender()%>
        </td>
        <td>
            <%=student.getStuScore()%>
        </td>
        <td>
            <%=student.getStuDate()%>
        </td>
        <td>
            <%=student.getStuHobby()%>
        </td>
        <td>
            <%=student.getStuDes()%>
        </td>
        <td>
            <a href="mvc?method=edit&stuId=<%=student.getStuId()%>">编辑</a>
            <a href="mvc?method=delete&stuId=<%=student.getStuId()%>"onclick="return deleteMethod()">删除</a>
        </td>
    </tr>
    <%}
    %>
</table>
</body>
</html>
<script src="js/delete.js" type="text/javascript"></script>
JSP前端的页面:编辑的页面
<%@ page import="com.Model.Student" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>学员信息的添加页面</title>
</head>
<body>
    <%
        Student  student=(Student)request.getAttribute("student");
        %>
<h2 style="color: red" align="center">学员信息的添加页面</h2>
<form  action="mvc?method=update" method="post" class="form" onsubmit="return varitore()">
    <table>
        <tr>
            <td>用户名:</td>
            <td>
                <input type="text" name="stuName" id="stuName" value="<%=student.getStuName()%>" style="background: aqua" placeholder="请输入用户名"></br>
            </td>
        </tr>
        <tr>
            <td>年龄:</td>
            <td>
                <input type="text" name="stuAge" id="stuAge"value="<%=student.getStuAge()%>" style="background: aqua" placeholder="请输入年龄"></br>
            </td>
        </tr>
        <tr>
            <td>学@历:</td>
            <td>
                <select name="stuXueli" id="stuXueli">
                    <%
                     if(student.getStuXueli()==0){ %>
                    <option selected value="0">小学</option>
                    <option value="1">初中</option>
                    <option value="2">高中</option>
                    <option value="3">大学</option>
                    <%}else if(student.getStuXueli()==1){%>
                    <option  value="0">小学</option>
                    <option selected value="1">初中</option>
                    <option value="2">高中</option>
                    <option value="3">大学</option>
                    <% }else if(student.getStuXueli()==2){ %>
                    <option  value="0">小学</option>
                    <option  value="1">初中</option>
                    <option selected value="2">高中</option>
                    <option value="3">大学</option>
                    <%}else if(student.getStuXueli()==3){%>
                    <option  value="0">小学</option>
                    <option  value="1">初中</option>
                    <option  value="2">高中</option>
                    <option selected value="3">大学</option>
                    <%}
                    %>
                </select>
            </td>
        </tr><br>
        <tr>
            <td>性  别:</td>
            <td>
                <%
                   if(student.getStuGender().equals("女")){%>
                        <input type="radio" name="stuGender" checked value="女">女
                        <input type="radio" name="stuGender" value="男">男</br>
                <%}else{%>
                     <input type="radio" name="stuGender" value="女">女
                     <input type="radio" name="stuGender" checked  value="男">男</br>
                <%}
                %>
            </td>
        <tr>
            <td>成@绩:</td>
            <td>
                <input type="text" name="stuScore" value="<%=student.getStuScore()%>" id="stuScore" style="background: aqua" placeholder="请输入成绩"><br>
            </td>
        </tr>
        <tr>
            <td>生  日:</td>
            <td>
                <input type="date" name="stuDate" id="stuDate"></br>
            </td>
        </tr>
        <tr>
            <td>爱@好:</td>
            <td>
                <%
                    String[]ars=student.getStuHobby().split("-");
                    boolean  f1=false;
                    boolean  f2=false;
                    boolean  f3=false;
                    for(int i=0;i<ars.length;i++){
                        if(ars[i].equals("play")){
                            f1=true;
                        }else if(ars[i].equals("sing")){
                            f2=true;
                        }else if(ars[i].equals("sleep")){
                            f3=true;
                        }
                    }
                    String s1=f1?"checked":"";
                    String s2=f2?"checked":"";
                    String s3=f3?"checked":"";
                %>
                <input type="checkbox" <%=s1%> name="stuHobby" value="play">篮球
                <input type="checkbox" <%=s2%>  name="stuHobby" value="sing">唱歌
                <input type="checkbox" <%=s3%> name="stuHobby" value="sleep">睡觉
            </td><br>
        </tr>
        <tr>
            <td>文本框:</td>
            <td>
                <textarea cols="30" rows="20" name="stuDes" style="background: salmon"><%=student.getStuDes()%></textarea>
            </td>
        </tr>
        <tr>
            <td colspan="2" align="center">
                <input type="submit" value="提交">
                <input type="reset"  value="重置">
            </td>
        </tr>
    </table>
    <!--设置隐藏域属性-->
    <input type="hidden" name="stuId" value="<%=student.getStuId()%>">
</form>
</body>
</html>
<script src="js/from.js" type="text/javascript"></script>

JSP前端的页面: 提示的页面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
  <head>
    <title>学员信息提示的页面</title>
  </head>
  <body>
  <h2 style="color: red">MVC_CRUD</h2>
  <h3 style="color:red"><a href="add_Stu.jsp">添加学员的信息</a></h3>
  <h3 style="color:red"><a href="mvc?method=list">学员信息查询的页面</a></h3>
  </body>
</html>
JSP前端的页面: 成功的页面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>信息的提示页面</title>
</head>
<body>

<h2 style="color: red"><%= request.getAttribute("MSG")%></h2>

</body>
</html>