WEB-CRUD

本次DAO模型之前展示过，本次不展示DAO

 

具体操作代码（未合并）：

前端页面：

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

    <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

学生信息表

新增学生

编号

姓名

年龄

操作

${item.id}

${item.name}

${item.age}

删除||编辑

 

 

 

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

    <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

${stu==null?"新增":"编辑"}学生

姓名：

年龄：

后台代码

删除页面：

package com._520it.pss.web.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._520it.pss.dao.IStudentDAO;

import com._520it.pss.dao.impl.StudentDAOImpl;

 

@WebServlet("/student/delete")

public class delete extends HttpServlet{

 

    /**

     *

     */

    private static final long serialVersionUID = 1L;

    private IStudentDAO dao;

    @Override

    public void init() throws ServletException {

        // TODO Auto-generated method stub

        dao=new StudentDAOImpl();

    }

    @Override

    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        // TODO Auto-generated method stub

        req.setCharacterEncoding("UTF-8");

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

        dao.delete(Long.valueOf(id));

        resp.sendRedirect("/student/list");

    }

}

 

edit页面（用于新增和编辑，传递id，根据id判断是新增还是编辑）：

package com._520it.pss.web.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._520it.pss.dao.IStudentDAO;

import com._520it.pss.dao.impl.StudentDAOImpl;

import com._520it.pss.domain.Student;

 

@WebServlet("/student/edit")

public class edit extends HttpServlet{

 

    /**

     *

     */

    private IStudentDAO dao;

    private static final long serialVersionUID = 1L;

    @Override

    public void init() throws ServletException {

        // TODO Auto-generated method stub

        dao=new StudentDAOImpl();

    }

    @Override

    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        // TODO Auto-generated method stub

        req.setCharacterEncoding("UTF-8");

        if(req.getParameter("id")!=null)

        {

            Student stu=dao.get(Long.valueOf(req.getParameter("id")));

            

            System.out.println(stu);

            req.setAttribute("stu", stu);

        }

        req.getRequestDispatcher("/WEB-INF/view/student/save.jsp").forward(req, resp);

    }

}

 

increase页面（新增和编辑）

package com._520it.pss.web.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._520it.pss.dao.IStudentDAO;

import com._520it.pss.dao.impl.StudentDAOImpl;

import com._520it.pss.domain.Student;

@WebServlet("/student/save")

public class increase extends HttpServlet{

 

    /**

     *

     */

    private static final long serialVersionUID = 1L;

    private IStudentDAO dao;

    @Override

    public void init() throws ServletException {

        // TODO Auto-generated method stub

        dao=new StudentDAOImpl();

    }

    @Override

    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        // TODO Auto-generated method stub

        req.setCharacterEncoding("UTF-8");

        String name=req.getParameter("user");

        String id=req.getParameter("shixian");

        System.out.println(id);

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

        Student stu=new Student(null,name,Integer.valueOf(age));

        if(id!=null&&!"".equals(id))

        {

            

            dao.update(Long.valueOf(id), stu);

        }else {

                

                dao.save(stu);

        }

        resp.sendRedirect("/student/list");

    

    }

}

 

student页面（用于传递值）

package com._520it.pss.web.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 com._520it.pss.dao.IStudentDAO;

import com._520it.pss.dao.impl.StudentDAOImpl;

import com._520it.pss.domain.Student;

import com.mysql.fabric.xmlrpc.base.Data;

@WebServlet("/student/list")

public class student extends HttpServlet{

 

    /**

     *

     */

    private IStudentDAO dao;

    private static final long serialVersionUID = 1L;

    

   

    public void init() throws ServletException {

        // TODO Auto-generated method stub

        dao=new StudentDAOImpl();

        

    }

    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        // TODO Auto-generated method stub

        List list=dao.list();

        req.setAttribute("list", list);

        req.getRequestDispatcher("/WEB-INF/view/student/list.jsp").forward(req, resp);

    }

}

 

效果如下

 

 

合并操作

package com._520it.pss.web.servlet;

import java.io.IOException;

import java.io.PrintWriter;

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._520it.pss.dao.IStudentDAO;

import com._520it.pss.dao.impl.StudentDAOImpl;

import com._520it.pss.domain.Student;

@WebServlet("/student")

public class jihe extends HttpServlet{

    /**

     *

     */

    private static final long serialVersionUID = 1L;

    private IStudentDAO dao;

    @Override

    public void init() throws ServletException {

     // TODO Auto-generated method stub

     dao=new StudentDAOImpl();

    }

    @Override

    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

     // TODO Auto-generated method stub

     req.setCharacterEncoding("UTF-8");

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

     switch (cmd) {

        case "edit":

            edit(req, resp);

            break;

        case "delete":

            delete(req, resp);

            break;

        case "saveORupdate":

            saveORupdate(req, resp);

            break;

        case "list":

            list(req, resp);

            break;

        default:

            PrintWriter out=resp.getWriter();

            out.println("请重新进行操作");

            break;

        }

    }

    protected void edit(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{

     

     if(req.getParameter("id")!=null)

     {

         Student stu=dao.get(Long.valueOf(req.getParameter("id")));

         

         System.out.println(stu);

         req.setAttribute("stu", stu);

     }

     req.getRequestDispatcher("/WEB-INF/view/student/save.jsp").forward(req, resp);

    }

    protected void delete(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{

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

     dao.delete(Long.valueOf(id));

     resp.sendRedirect("/student/list");

    }

    protected void saveORupdate(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{

     String name=req.getParameter("user");

     String id=req.getParameter("shixian");

          System.out.println(id);

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

     System.out.println(id+","+name+","+age);

     Student stu=new Student(null,name,Integer.valueOf(age));

    boolean a="".equals(id);

    System.out.println(a);

     if(id!=null&&!"".equals(id))

     {

         

         dao.update(Long.valueOf(id), stu);

     }else {

                System.out.println(stu);

             dao.save(stu);

     }

        resp.sendRedirect("/student/list");

   

    }

    protected void list(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{

     List list=dao.list();

     req.setAttribute("list", list);

     req.getRequestDispatcher("/WEB-INF/view/student/list.jsp").forward(req, resp);

    }

}

同样可以实现上面的结果

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" %>

    

学生信息表

    新增学生

    

        

            

            

            

            

        

        

        

            

            

            

            

        

        

    

编号	姓名	年龄	操作
${item.id}	${item.name}	${item.age}	删除||编辑

 

save.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

    <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

    

${stu==null?"新增":"编辑"}学生

    

    

        姓名：

        年龄：