开发工具：MyEclipse 6.0 ，Tomcat 5.5 ，JDK 1.5 ，MySQL 5.0 ；开发准备：下载Struts 2.0和Hibernate 3.2，大家可Struts和Hibernate的官方网站下载这两个框架。我们先来总览一下开发完成后的包—类图：
首先NEW一个Web Project ，名为"LoginSystem" ，在 lib 目录下加入Struts 2.0的Jar包和Hibernate 3.2的Jar包，然后按下面的步骤来：
1、在 src 目录下建 "hibernate.cfg.xml" 全部代码如下：
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="connection.username">root</property>
<property name="connection.url">
jdbc:mysql://localhost:3306/testmysql
</property>
<property name="dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="myeclipse.connection.profile">
mysql
</property>
<property name="connection.password">root</property>
<property name="connection.driver_class">
com.mysql.jdbc.Driver
</property>
<property name="show_sql">true</property>
<!-- POJO类映射配置 -->
<mapping resource="com/rong/ORM/User.hbm.xml" />
</session-factory>
</hibernate-configuration>
2、建立实体类 "User.java" 及其映射文件 "User.hbm.xml" 两者都放在 "com.rong.ORM" 包下。其中"User.java"的代码如下：
package com.rong.ORM;
public class User {
private int id; //主键ID
private String name; //用户名
private String pwd; //密码
/*
* Getter方法与Setter方法
*/
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
}
User.hbm.xml的代码如下：
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.rong.ORM.User" table="tb_user">
<id name="id">
<generator class="native"/>
</id>
<property name="name" type="java.lang.String" length="20"/>
<property name="pwd" type="java.lang.String" length="20"/>
</class>
</hibernate-mapping>
3、建立"ExportDB.java"工具类，我们执行如下代码，就能轻松将User类导入数据库转变成数据库中的表。不过，前提是我们已经在MySQL中建立了一个名为"LoginSystem"的数据库。
package tool;
import org.hibernate.cfg.Configuration;
import org.hibernate.tool.hbm2ddl.SchemaExport;
public class ExportDB {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Configuration cfg = new Configuration().configure();
SchemaExport export = new SchemaExport(cfg);
export.create(true, true);
}
}
4、建立获取SessionFactory和管理Session的HibernateUtil.java类：
package com.rong.hibernate;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
//声明Hibernate配置文件所在的路径
private static String configFile = "/hibernate.cfg.xml";
//建Configuration对象
private static Configuration configuration = new Configuration();
//建Session工厂对象
private static SessionFactory sessionFactory = null;
/**
* 单例模式,只初始化一次,只产生一个SessionFactory对象(线程安全)
*/
static {
try{
//通过hibernate.cfg.xml配置数据库连接
configuration.configure(configFile);
//建立一个Session工厂
sessionFactory = configuration.buildSessionFactory();
System.out.println("[标记]初始化SessionFactory");
}catch(Exception e){
System.out.println("[异常]创建SessionFactory时发生异常,异常原因如下:");
e.printStackTrace();
}
}
/**
* getSession()方法
* @return Session对象
* @throws HibernateException
*/
public Session getSession(){
Session session = null;
try{
session = sessionFactory.openSession();
}catch(Exception e){
System.out.println("[异常]开启Session时发生异常,异常原因如下:");
e.printStackTrace();
}
return session;
}
/**
* closeSession()方法
* @param session 要关闭的Session对象
*/
public void closeSession(Session session){
try{
if(null != session)
session.close();
}catch(Exception e){
System.out.println("[异常]关闭Session时发生异常,异常原因如下:");
e.printStackTrace();
}
}
}
5、DAO层设计：在"com.rong.DAO" 包下建立两个类，一个是接口，一个是实现类，其中UserDao.java代码如下：
package com.rong.DAO;
import java.util.List;
import com.rong.ORM.User;
public interface UserDao {
/**
* 增加用户
* @param user 要增加的用户
*/
public void add(User user);
/**
* 登录验证
* @param name
* @param password
* @return -1:不存在用户名 ; -2:密码不正确 ; >0:登录成功(即返回该记录ID)
*/
public int isExist(String name,String password);
}
UserDaoImpl.java的代码如下
package com.rong.DAO;
import java.util.Iterator;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import com.rong.ORM.User;
import com.rong.hibernate.HibernateUtil;
public class UserDaoImpl implements UserDao {
HibernateUtil util = new HibernateUtil();
/**
* 增加用户
* @param user 要增加的用户
*/
public void add(User user){
Session session = util.getSession();
Transaction ts = null;
try{
ts = session.beginTransaction();
session.save(user);
ts.commit();
}catch(Exception e){
System.out.println("UserDaoImpl.add()方法发生异常:");
e.printStackTrace();
}finally{
util.closeSession(session);
}
}
/**
* 登录验证
* @param name
* @param password
* @return -1:不存在用户名 ; -2:密码不正确 ; >0:登录成功(即返回该记录ID)
*/
public int isExist(String name,String password){
//int state = 0 ; //初始化状态变量
Session session = util.getSession();
try{
Query query = session.createQuery("from User u where u.name = ?");
query.setString(0, name);
List list = query.list();
if(null == list || 0 == list.size()){
return -1 ; //用户名不存在
}
Query query2 = session.createQuery("from User u where u.name = ? and u.pwd = ?");
query2.setString(0, name);
query2.setString(1, password);
List list2 = query.list();
if(null == list2){
return -2 ; //密码不正确
}
Iterator it = list.iterator();
User user = (User)it.next();
return user.getId(); //验证成功,取ID值
}catch(Exception e){
System.out.println("UserDaoImpl.isExist()方法发生异常:");
e.printStackTrace();
return 0; //异常时返回0
}finally{
util.closeSession(session);
}
}
}
6、在web.xml中配置Struts 2.0支持：
<?xml version="1.0" encoding="UTF-8"?>
<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">
<!-- 用过滤器配置Struts2支持 -->
<filter>
<filter-name>struts2</filter-name>
<filter-class>
org.apache.struts2.dispatcher.FilterDispatcher
</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
7、登录页面login.jsp代码如下：
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Login Page</title>
</head>
<body>
<p><a href="register.jsp">用户注册</a>|用户登录</p>
<s:form action="loginAction" theme="simple">
<table>
<tr>
<td style="text-align:right">
账号
</td>
<td>
<s:textfield name="name" label="账号" />
</td>
</tr>
<tr>
<td style="text-align:right">
密码
</td>
<td>
<s:password name="pwd" label="密码" />
</td>
</tr>
<tr>
<td style="text-align:right">
验证码
</td>
<td>
<s:textfield name="inputCertCode" label="验证码" cssStyle="100px"/>
<img src="makeCertPic.jsp">
</td>
</tr>
<tr>
<td style="text-align:right">
<s:submit value="登录" />
</td>
<td style="text-align:left">
<s:reset value="取消"/>
</td>
</tr>
</table>
</s:form>
<s:fielderror cssStyle="color:red"/>
</body>
</html>
注册页register.jsp代码如下
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Register Page</title>
</head>
<body>
<p><a href="login.jsp">用户登录</a>|用户注册</p>
<s:form action="registerAction" theme="simple" method="post">
<table>
<tr>
<td style="text-align:right">
请输入账号
</td>
<td>
<s:textfield name="user.name" label="账号" />
</td>
</tr>
<tr>
<td style="text-align:right">
请输入密码
</td>
<td>
<s:password name="user.pwd" label="密码" />
</td>
</tr>
<tr>
<td style="text-align:right">
请再次输入密码
</td>
<td>
<s:password name="repwd" label="重复密码" />
</td>
</tr>
<tr>
<td style="text-align:right">
请输入验证码
</td>
<td>
<s:textfield name="inputCertCode" label="验证码" cssStyle="100px"/>
<img src="makeCertPic.jsp">
</td>
</tr>
<tr>
<td style="text-align:right">
<s:submit value="注册" />
</td>
<td style="text-align:left">
<s:reset value="取消"/>
</td>
</tr>
</table>
</s:form>
<s:fielderror cssStyle="color:red"/>
</body>
</html>
8、在JSP页中所用到的验证码的生成页面makeCertPic.jsp（我们把它放在WebRoot的other目录下）：
<%@page contentType="image/jpeg" pageEncoding="gbk"%>
<jsp:useBean id="image" scope="page" class="com.rong.other.makeCertPic" />
<%
String str = image.getCertPic(0,0,response.getOutputStream());
// 将验证码保存到Session中
session.setAttribute("certCode", str);
%>
其中，它调用了名为makeCertPic的Bean ，这个类主要用来生成彩色的验证图片，其代码如下：
package com.rong.other;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
/**
* 生成验证码图片
*/
public class makeCertPic {
//验证码图片中可以出现的字符集,可根据需要修改
private char mapTable[]={
'a','b','c','d','e','f',
'g','h','i','j','k','l',
'm','n','o','p','q','r',
's','t','u','v','w','x',
'y','z','0','1','2','3',
'4','5','6','7','8','9'};
/**
* 功能:生成彩色验证码图片
* 参数width为生成的图片的宽度,参数height为生成的图片的高度,参数os为页面的输出流
*/
public String getCertPic(int width, int height, OutputStream os) {
if(width<=0)width=60;
if(height<=0)height=20;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
// 设定背景色
g.setColor(new Color(0xDCDCDC));
g.fillRect(0, 0, width, height);
//画边框
g.setColor(Color.black);
g.drawRect(0,0,width-1,height-1);
// 取随机产生的认证码
String strEnsure = "";
// 4代表4位验证码,如果要生成更多位的认证码,则加大数值
for(int i=0; i<4; ++i) {
strEnsure += mapTable[(int)(mapTable.length*Math.random())];
}
// 将认证码显示到图象中,如果要生成更多位的认证码,增加drawString语句
g.setColor(Color.black);
g.setFont(new Font("Atlantic Inline",Font.PLAIN,18));
String str = strEnsure.substring(0,1);
g.drawString(str,8,17);
str = strEnsure.substring(1,2);
g.drawString(str,20,15);
str = strEnsure.substring(2,3);
g.drawString(str,35,18);
str = strEnsure.substring(3,4);
g.drawString(str,45,15);
// 随机产生10个干扰点
Random rand = new Random();
for (int i=0;i<10;i++) {
int x = rand.nextInt(width);
int y = rand.nextInt(height);
g.drawOval(x,y,1,1);
}
// 释放图形上下文
g.dispose();
try {
// 输出图象到页面
ImageIO.write(image, "JPEG", os);
} catch (IOException e) {
return "";
}
return strEnsure;
}
}
9、此时，我们很有必要来配置一下struts.xml其全部代码如下
<?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>
<package name="com.rong.action" extends="struts-default">
<!-- 用户登录 -->
<action name="loginAction" class="com.rong.action.LoginAction">
<result name="success" type="redirect">/back/index.jsp</result>
<result name="input">/login.jsp</result>
</action>
<!-- 用户注册 -->
<action name="registerAction" class="com.rong.action.RegisterAction">
<result name="success" type="redirect">/login.jsp</result>
<result name="input">/register.jsp</result>
</action>
</package>
</struts>
10、Action层设计：两个非常关键的类，其中LoginAction.java的代码如下：
package com.rong.action;
import java.util.Map;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.rong.DAO.UserDao;
import com.rong.DAO.UserDaoImpl;
import com.rong.ORM.User;
public class LoginAction extends ActionSupport {
private UserDao userDao = new UserDaoImpl(); //操纵数据库DAO类(Hibernate实现),通过Struts.xml注入值
private int id;
private String name; //用户名(值由struts注入)
private String pwd; //密码(值由struts注入)
private String inputCertCode; //验证码
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 getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
public String getInputCertCode() {
return inputCertCode;
}
public void setInputCertCode(String inputCertCode) {
this.inputCertCode = inputCertCode;
}
@Override
public String execute() throws Exception {
int state = userDao.isExist(name,pwd);
System.out.println("state="+state);
if(state == -1){
this.addFieldError("name", "用户名不正确,请先注册!");
return INPUT;
}else if(state == -2){
this.addFieldError("pwd", "密码不正确,请重新输入密码!");
return INPUT;
}else if(state > 0){
System.out.println("[测试]登录成功!用户ID="+state);
this.setId(state);
return SUCCESS;
}else{
this.addFieldError("name", "登录失败,请与管理员联系!");
return INPUT;
}
}
public void validate() {
//验证码验证
if(null == inputCertCode || "".equals(inputCertCode)){
this.addFieldError("inputCertCode", "验证码不能为空!");
}else{
Map session = ActionContext.getContext().getSession();
String certCode = session.get("certCode").toString();
if( ! certCode.equals(this.inputCertCode)){
this.addFieldError("inputCertCode", "验证码不正确!");
}
}
}
}
RegisterAction.java的代码如下：
package com.rong.action;
import java.util.Map;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.rong.DAO.UserDao;
import com.rong.DAO.UserDaoImpl;
import com.rong.ORM.User;
public class RegisterAction extends ActionSupport {
private UserDao userDao = new UserDaoImpl();
private User user; //注册提交的用户对象
private String repwd; //重复密码
private String inputCertCode; //验证码
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public String getRepwd() {
return repwd;
}
public void setRepwd(String repwd) {
this.repwd = repwd;
}
public String getInputCertCode() {
return inputCertCode;
}
public void setInputCertCode(String inputCertCode) {
this.inputCertCode = inputCertCode;
}
@Override
public String execute() throws Exception {
userDao.add(user); //保存注册的user对象
return SUCCESS;
}
/* @Override
public void validate() {
//验证码验证
if(null == inputCertCode || "".equals(inputCertCode)){
this.addFieldError("inputCertCode", "验证码不能为空!");
}else{
Map session = ActionContext.getContext().getSession();
String certCode = session.get("certCode").toString();
if( ! certCode.equals(this.inputCertCode)){
this.addFieldError("inputCertCode", "验证码不正确!");
}
}
}*/
}
11、不要忘记配置校验框架，与上面两个Action同一个目录下。LoginAction-validation.xml代码如下：
<!DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN"
"http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">
<validators>
<!-- 用户名验证 -->
<field name="name">
<field-validator type="requiredstring">
<param name="trim">true</param>
<message>用户名不能为空!</message>
</field-validator>
<field-validator type="regex">
<param name="expression"><![CDATA[(w{4,8})]]></param>
<message>账号必须是长度为4-8的数字或字母！</message>
</field-validator>
</field>
<!-- 密码验证 -->
<field name="pwd">
<field-validator type="requiredstring">
<param name="trim">true</param>
<message>密码不能为空!</message>
</field-validator>
<field-validator type="regex">
<param name="expression"><![CDATA[(w{4,8})]]></param>
<message>密码必须长度为4-8的数字或字母！</message>
</field-validator>
</field>
</validators>
RegisterAction-validation.xml代码如下：
<!DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN"
"http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">
<validators>
<!-- 用户名验证 -->
<field name="user.name">
<field-validator type="requiredstring">
<param name="trim">true</param>
<message>用户名不能为空!</message>
</field-validator>
<field-validator type="regex">
<param name="expression"><![CDATA[(w{4,8})]]></param>
<message>账号必须是长度为4-8的数字或字母！</message>
</field-validator>
</field>
<!-- 密码验证 -->
<field name="user.pwd">
<field-validator type="requiredstring">
<param name="trim">true</param>
<message>密码不能为空!</message>
</field-validator>
<field-validator type="regex">
<param name="expression"><![CDATA[(w{4,8})]]></param>
<message>密码必须长度为4-8的数字或字母！</message>
</field-validator>
</field>
<field name="repwd">
<field-validator type="requiredstring" short-circuit="true">
<param name="trim">true</param>
<message>重复密码不能为空!</message>
</field-validator>
<field-validator type="fieldexpression">
<param name="expression"><![CDATA[(repwd==user.pwd)]]></param>
<message>两次输入的密码要一致!</message>
</field-validator>
</field>
</validators>
到这里，我们的项目也差不多完成了，大家自己也尝试一下，开发出自己的J2EE系统。