JSP connection database operations written in MVC mode

First, use a JavaBean to encapsulate the database operation, which is the model in MVC

Jdbcbean.java

package data;import java.sql.*;p ublic class Jdbcbean {private String dbdriver= "  Com.mysql.jdbc.Driver ";  Private String dburl= "Jdbc:mysql://localhost:3306/test";  Private String dbuser= "root";  Private String dbpassword= "686175";  Public Connection Conn=null;  Public ResultSet Rs=null;  Public ResultSet query (String sql) throws exception{try{Class.forName (dbdriver);  Conn=drivermanager.getconnection (Dburl,dbuser,dbpassword);  Statement stmt=conn.createstatement ();  Rs=stmt.executequery (SQL);  Return RS;  } catch (SQLException e) {System.out.println (E.getmessage ());  } return null;  public void update (String sql) throws exception{try{Class.forName (dbdriver);  Conn=drivermanager.getconnection (Dburl,dbuser,dbpassword);  Statement stmt=conn.createstatement ();  Stmt.executeupdate (SQL);  Stmt.close ();  Conn.close ();  } catch (SQLException e) {System.out.println (E.getmessage ()); }  }}

In the SRC data package There is also a controller servlet, which is used to handle the operation of the connection database, the database used in the project is MySQL

Loginservlet.java

Package Data;import Java.io.ioexception;import Java.sql.resultset;import javax.servlet.requestdispatcher;import Javax.servlet.servletexception;import Javax.servlet.http.httpservlet;import Javax.servlet.http.httpservletrequest;import Javax.servlet.http.httpservletresponse;public class LoginServlet Extends HttpServlet {public void DoPost (HttpServletRequest request, httpservletresponse response) throws Servlete Xception, IOException {String tojsp= ""; Request.setcharacterencoding ("GBK"); Response.setcontenttype ("text/html; CHARSET=GBK "); String Username=request.getparameter ("username"); String password=request.getparameter ("password"); String sql= "SELECT * from user where username= '" +username+ "'" + "&&password= '" +password+ "'"; Jdbcbean jdbc=new Jdbcbean () try{resultset rs=jdbc.query (SQL), if (Rs.next ()) {tojsp= "success.jsp";} else{tojsp= "error.jsp";} Rs.close ();} catch (Exception e) {System.out.println ("query exception occurred");} RequestDispatcher Rd=request.getrequestdispatcher (tojsp); Rd.forward (requesT, response);} public void doget (HttpServletRequest request, httpservletresponse response) throws Servletexception, Ioexceptio    n {doPost (request,response); }}

Next is a JSP-written view that shows the page action

Login Page login.jsp

<%@ page language= "java" import= "java.util.*" pageencoding= "Utf-8"%>Login Success Page success.jsp
<%@ page language= "java" import= "java.util.*" pageencoding= "Utf-8"%>
If the login user name and password are not on the database, the login error page is displayed error.jsp
<%@ page language= "java" import= "java.util.*" pageencoding= "Utf-8"%>

Enter user name Ming, password Ming

Enter user name Lin, password li


Full Code Package: http://download.csdn.net/detail/u011731233/8093745

JSP connection database operations written in MVC mode