Adding and deleting information management system

code in the modification of the update has some flaws, you should first change the corresponding part of the query display and then modify. In fact, the principle of completing the increase and deletion check is the same as login registration.
1. First build the student class.

public class Studentmodel {private int id;private string Name;private string grade;private string gender;private int age;p rivate String address;public int getId () {return ID;} public void setId (int id) {this.id = ID;} Public String GetName () {return name;} public void SetName (String name) {this.name = name;} Public String Getgrade () {return grade;} public void Setgrade (String grade) {This.grade = grade;} Public String Getgender () {return gender;} public void Setgender (String gender) {This.gender = gender;} public int getage () {return age;} public void Setage (int.) {this.age = age;} Public String getaddress () {return address;} public void setaddress (String address) {this.address = address;}}

2.1) Build the interface class.

Package Cn.edu.hpu.service;import Cn.edu.hpu.model.studentmodel;public Interface Student {public Boolean addstu ( Studentmodel Studentmodel);    public boolean delstu (int id);    public boolean updstu (int id,studentmodel studentmodel);    

2) Implementation of the interface class

Package Cn.edu.hpu.service;import Java.sql.preparedstatement;import Java.sql.resultset;import Java.sql.sqlexception;import Com.mysql.jdbc.connection;import Cn.edu.hpu.model.studentmodel;import Cn.edu.hpu.util.util;public class Studentimpl implements Student {@Overridepublic Boolean addstu (Studentmodel Studentmodel) {Boolean flag=false; String sql= "INSERT into Student1 (id,name,grade,gender,age,address) value (?,?,?,?,?,?)"; Connection conn=util.getconnection (); PreparedStatement pst;try {PST = conn.preparestatement (SQL);p st.setint (1, Studentmodel.getid ());p st.setstring (2, Studentmodel.getname ());p st.setstring (3, Studentmodel.getgrade ());p st.setstring (4, Studentmodel.getgender ()); Pst.setint (5, Studentmodel.getage ());p st.setstring (6, studentmodel.getaddress ());p st.executeupdate (); flag=true;} catch (SQLException e) {//TODO auto-generated catch Blocke.printstacktrace ();} return flag;} @Overridepublic boolean delstu (int id) {Boolean flag=false; String sql= "Delete from student1 where id=" +ID; Connection Conn=util.getconnection (); try {preparedstatement pst=conn.preparestatement (SQL);p st.executeupdate (); flag= true;} catch (SQLException e) {//TODO auto-generated catch Blocke.printstacktrace ();} return flag;} @Overridepublic boolean updstu (int id, Studentmodel studentmodel) {Boolean flag=false; String sql= "Update student1 set id=?,name=?,grade=?,gender=?,age=?,address=? where id= "+ID; Connection conn=util.getconnection (); PreparedStatement pst;try {PST = conn.preparestatement (SQL);p st.setint (1, Studentmodel.getid ());p st.setstring (2, Studentmodel.getname ());p st.setstring (3,studentmodel.getgrade ());p st.setstring (4, Studentmodel.getgender ()); Pst.setint (5, Studentmodel.getage ());p st.setstring (6, studentmodel.getaddress ());p st.executeupdate (); flag=true;} catch (SQLException e) {//TODO auto-generated catch Blocke.printstacktrace ();} return flag;} @Overridepublic Studentmodel selstu (int id) {Studentmodel studentmodel=new studentmodel (); String sql= "SELECT * from Student1 where id=?"; Connection ConN=util.getconnection (); try {preparedstatement pst=conn.preparestatement (SQL);p st.setint (1,id); ResultSet Rs=pst.executequery (); while (Rs.next ()) {//Traversal result set Studentmodel.setid (Rs.getint ("id")); Studentmodel.setname (rs.getstring ("name")); Studentmodel.setgrade (Rs.getstring ("grade")); Studentmodel.setgender (Rs.getstring ("Gender")), Studentmodel.setage (Rs.getint ("Age")), Studentmodel.setaddress (rs.getstring ("address") );}} catch (SQLException e) {//TODO auto-generated catch Blocke.printstacktrace ();} TODO auto-generated method Stubreturn Studentmodel;}}

3. Create a servlet for each interface method. 1) Added servlet

Package Cn.edu.hpu.servlet;import Java.io.ioexception;import Javax.servlet.servletexception;import Javax.servlet.http.httpservlet;import Javax.servlet.http.httpservletrequest;import Javax.servlet.http.httpservletresponse;import Cn.edu.hpu.model.studentmodel;import cn.edu.hpu.service.Student; Import Cn.edu.hpu.service.studentimpl;public class Tianjia extends HttpServlet {/** * */private static final long Serialv Ersionuid = 1l;public void doget (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {doPost (request,response);} public void DoPost (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {        Request.setcharacterencoding ("Utf-8"); int Id = Integer.parseint (Request.getparameter ("id"));        String name=request.getparameter ("Name");        String grade=request.getparameter ("Grade");        String gender=request.getparameter ("Gender");        int Age=integer.parseint (Request.getparameter ("Age")); String address=request.getparameter ("Address");        Studentmodel studentmodel=new Studentmodel ();        Studentmodel.setid (ID);        Studentmodel.setname (Name);        Studentmodel.setgrade (Grade);        Studentmodel.setgender (Gender);        Studentmodel.setage (age);                Studentmodel.setaddress (Address);        Student stu=new Studentimpl ();        Boolean flag=stu.addstu (Studentmodel);        if (flag) {Studentdaoservlet s=new studentdaoservlet ();        S.dopost (request, response); }}}

2) Delete the servlet.

Package Cn.edu.hpu.servlet;import Java.io.ioexception;import Javax.servlet.servletexception;import Javax.servlet.http.httpservlet;import Javax.servlet.http.httpservletrequest;import Javax.servlet.http.httpservletresponse;import Cn.edu.hpu.model.studentmodel;import cn.edu.hpu.service.Student; Import Cn.edu.hpu.service.studentimpl;public class Shanchu extends HttpServlet {/** * */private static final long Serialv Ersionuid = 1l;public void doget (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {doPost (request,response);} public void DoPost (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {      Request.setcharacterencoding ("UTF-8"); int id=integer.parseint (Request.getparameter ("Id")); Studentmodel studentmodel=new Studentmodel (); Studentmodel.setid (Id); Student stu=new Studentimpl (); Boolean flag=stu.delstu (Id); if (flag) {Studentdaoservlet s=new studentdaoservlet (); S.dopost (request, response);} <spAn style= "font-family:kaiti_gb2312;" >}}</span>

3) Updated servlet.

Package Cn.edu.hpu.servlet;import Java.io.ioexception;import Javax.servlet.servletexception;import Javax.servlet.http.httpservlet;import Javax.servlet.http.httpservletrequest;import Javax.servlet.http.httpservletresponse;import Cn.edu.hpu.model.studentmodel;import cn.edu.hpu.service.Student; Import Cn.edu.hpu.service.studentimpl;public class Gengxin extends HttpServlet {/** * */private static final long Serialv Ersionuid = 1l;public void doget (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {doPost (request,response);}            public void DoPost (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {            Request.setcharacterencoding ("UTF-8");            int Id=integer.parseint (Request.getparameter ("Id"));            String name=request.getparameter ("Name");            String grade=request.getparameter ("Grade");            String gender=request.getparameter ("Gender"); int AGE=INTEGER.PArseint (Request.getparameter ("Age"));                        String address=request.getparameter ("Address");            Studentmodel studentmodel=new Studentmodel ();            Studentmodel.setid (ID);            Studentmodel.setname (Name);            Studentmodel.setgrade (Grade);            Studentmodel.setgender (Gender);            Studentmodel.setage (age);                        Studentmodel.setaddress (Address);            Student stu=new Studentimpl ();            Boolean Flag=stu.updstu (Id, Studentmodel);            if (flag) {Studentdaoservlet s=new studentdaoservlet ();            S.dopost (request, response); }             }}

4) Query the servlet. The above is completed the deletion and modification of the operation.
4. Build a JSP page. This is the page that jumps to when login registration is complete. There are add, delete, modify, query hyperlinks, click to jump to the corresponding page can be done accordingly.

<%@ page language= "java" import= "java.util.*" pageencoding= "Utf-8"%><%@ taglib prefix= "C" uri= "/HTTP/ Java.sun.com/jsp/jstl/core "%><! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" >
At this point to complete the deletion and modification of the corresponding operation.
Adding and deleting information management system