Struts2 + MySql 数据库实现登录

原文地址 ：http://liyazhouhappy.blog.163.com/blog/static/1777910542012719101644256/

Struts2 + MySql 数据库实现登录  

2012-08-19 10:33:36|  分类： 4. Struts2|举报|字号 订阅

一、搭建Struts2环境

1.所需Jar包：（需要添加MySql数据库驱动）

         commons-fileupload-1.2.1.jar
         commons-logging-1.0.4.jar
         freemarker-2.3.13.jar
         mysql-connector-java-5.1.6-bin.jar
         ognl-2.6.11.jar
         struts2-core-2.1.6.jar
         xwork-2.1.2.jar
2.配置web.xml

<?xml version="1.0" encoding="gbk"?><web-app version="2.5"  xmlns="http://java.sun.com/xml/ns/javaee"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee  http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">  <welcome-file-list>    <welcome-file>login.jsp</welcome-file>  </welcome-file-list>  <!--编码 -->  <filter>    <filter-name>encodingFilter</filter-name>    <filter-class>com.login.filter.EncodingFilter</filter-class>   </filter>    <filter-mapping>    <filter-name>encodingFilter</filter-name>    <url-pattern>/*</url-pattern>   </filter-mapping>
<!--Struts2拦截器配置-->     <filter>        <filter-name>struts2</filter-name>        <filter-class>
           org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
        </filter-class>    </filter>
    <filter-mapping>        <filter-name>struts2</filter-name>        <url-pattern>/*</url-pattern>    </filter-mapping></web-app>

3.Struts.xml配置

 <?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE struts PUBLIC    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"    "http://struts.apache.org/dtds/struts-2.0.dtd">
<struts> <include file="struts-default.xml" /> <constant name="struts.locale" value="zh_CN"/> <constant name="struts.i18n.encoding" value="GBK"/>     <package name="lee" namespace="/" extends="struts-default">        <action name="login" class="com.loginAction.LoginAction">            <result name="success">/success.jsp</result>            <result name="login">/error.jsp</result>        </action>    </package>
</struts>

4.创建数据库login，然后在数据库login中创建一个user表，该表有两个字段username和password，字段类型为varchar类型。然后再输入两条记录
     
二、编写Java代码

1.建立一个com.login.filter包，在包下新建一个Java类
package com.login.filter;
import java.io.IOException;
import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;
public class EncodingFilter implements Filter {
 public void destroy() {  // TODO Auto-generated method stub
 }
 public void doFilter(ServletRequest arg0, ServletResponse arg1,   FilterChain arg2) throws IOException, ServletException {  // TODO Auto-generated method stub  arg0.setCharacterEncoding("GBK");  arg2.doFilter(arg0, arg1); }
 public void init(FilterConfig arg0) throws ServletException {  // TODO Auto-generated method stub
 }
}
2.创建一个com.loginAction包，在该包下新建一个Java类
package com.loginAction;
import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.Statement;
import com.opensymphony.xwork2.ActionSupport;
public class LoginAction extends ActionSupport { private String username; private String password; public String getUsername() {  return username; } public void setUsername(String username) {  this.username = username; } public String getPassword() {  return password; } public void setPassword(String password) {  this.password = password; } public String execute(){  boolean flag=Login(username,password);  if(flag)   return SUCCESS;  else   return LOGIN; }   /*验证登录是否成功*/ public boolean Login(String username,String password){  boolean flag=false;  Connection conn = null;  ResultSet rs = null;  Statement stmt = null;     String DBDriver = "com.mysql.jdbc.Driver";  try{   Class.forName(DBDriver);   conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/login", "root", "root");     stmt=conn.createStatement();   System.out.println("测试连接！");   System.out.println(username);   rs = stmt.executeQuery("select * from user where username ='" + username +"' and password = '"+ password+"'");   if(rs.next()){    System.out.println("登录成功！");    flag=true;    }  }catch(Exception e){   System.out.print("连接错误！");   e.printStackTrace();  }  return flag; }   }
三、编写页面代码

需要3个页面login.jsp、success.jsp和error.jsp

1.login.jsp页面代码：
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<html>    <body>    <center><h2>    <form action="login" method="post">  用户名:<input name="username"/><br/>  密&nbsp&nbsp码:<input name="password"/><br/>  <input value="登录" type="submit"><input type="reset" value="取消"/> </form>  </body></html> 
2.success.jsp页面代码:
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<html>  <body>    <center><h1>登录成功！</h1></center> <br>  </body></html> 
3.error.jsp页面代码：
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<html>  <body>    <center><h1>登录失败！</h1> <br>    <a href="login.jsp">返回登录页面<a/>  </body></html> 
四、运行结果

运行项目，实现登录功能。