StrutsPrepareAndExecuteFilter作用详解： https://blog.csdn.net/clk_esunny/article/details/80293978
过滤器和拦截器
package db;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
public class MyHibernateSessionFactory {
private static SessionFactory sessionFactory;//会话工厂属性
//构造方法私有化，保证单例模式
private MyHibernateSessionFactory()
{
}
//共有的静态方法，获得会话工厂对象
public static SessionFactory getSessionFactory()
{
if(sessionFactory==null)//未初始化
{
//创建配置对象
Configuration config = new Configuration().configure();
ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();
sessionFactory = config.buildSessionFactory(serviceRegistry);
return sessionFactory;
}
else//已经初始化
{
return sessionFactory;
}
}
}
ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();初始化sessionFactory
sessionFactory = config.buildSessionFactory(serviceRegistry);Session工作原理
session对象主要用于属性操作和会话管理，常用方法如下：
package service.impl;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import db.MyHibernateSessionFactory;
import service.UsersDAO;
import staffentity.Users;
public class UsersDAOImpl implements UsersDAO{
@Override
public boolean usersLogin(Users u) {
// TODO Auto-generated method stub
//事务对象
Transaction tx = null;
String hql = "";
try
{
Session session = MyHibernateSessionFactory.getSessionFactory().getCurrentSession();
tx = session.beginTransaction();
hql = "from Users where username=:username and password=:password ";
Query query = session.createQuery(hql);
query.setParameter("username", u.getUsername());
query.setParameter("password", u.getPassword());
List list = query.list();
tx.commit();//提交事务
if(list.size()>0){
return true;
}else {
return false;
}
}
catch (Exception ex){
ex.printStackTrace();
return false;
}
finally {
if(tx!=null)
{
tx = null;
}
}
}
}
Struts2中通常直接使用Action来封装HTTP请求参数，因此，Action类里还应该包含与请求参数对应的属性，并且为属性提供对应的getter和setter方法。
ActionSupport类是一个工具类，它已经实现了Action接口。除此之外，它还实现了Validateable接口，提供了数据校验功能。通过继承该ActionSupport类，可以简化Struts 2的Action开发。
在Validatable接口中定义了一个validate()方法，重写该方法，如果校验表单输入域出现错误，则将错误添加到ActionSupport类的fieldErrors域中，然后通过OGNL表达式负责输出。
为了让Struts 2增加输入数据校验的功能，改写程序中的LoginAction，增加重写validate方法。
(数据校验:应用中，即使浏览者输入任何用户名、密码，系统也会处理用户请求。在我们整个应用中，这种空用户名、空密码的情况不会引起太大的问题。但如果数据需要保存到数据库，或者需要根据用户输入的用户名、密码查询数据，这些空输入可能引起异常。
为了避免用户的输入引起底层异常，通常我们会在进行业务逻辑操作之前，先执行基本的数据校验。)
package action;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;
import org.apache.struts2.util.ServletContextAware;
import com.opensymphony.xwork2.ActionSupport;
//所有Action动作的父类
public class SuperAction extends ActionSupport implements ServletRequestAware,ServletResponseAware,ServletContextAware{
/**
*
*/
private static final long serialVersionUID = 1L;
protected HttpServletRequest request;//请求对象
protected HttpServletResponse response;//响应对象
protected HttpSession session;//会话对象
protected ServletContext application;//全局对象
@Override
public void setServletContext(ServletContext application) {
// TODO Auto-generated method stub
this.application = application;
}
@Override
public void setServletResponse(HttpServletResponse response) {
// TODO Auto-generated method stub
this.response = response;
}
@Override
public void setServletRequest(HttpServletRequest request) {
// TODO Auto-generated method stub
this.request = request;
this.session = this.request.getSession();
}
}
package action;
import org.apache.struts2.interceptor.validation.SkipValidation;
import com.opensymphony.xwork2.ModelDriven;
import service.UsersDAO;
import service.impl.UsersDAOImpl;
import staffentity.Users;
public class UsersAction extends SuperAction implements ModelDriven<Users>{
/**
*
*/
private static final long serialVersionUID = 1L;
private Users user = new Users();
//用户登录动作
public String login() {
UsersDAO udao = new UsersDAOImpl();
if(udao.usersLogin(user))
{
//在session中保存登录成功的用户名
session.setAttribute("loginUserName", user.getUsername());
return "login_success";
}
else
{
return "login_failure";
}
}
@SkipValidation
//用户注销方法
public String logout() {
if(session.getAttribute("loginUserName")!=null)
{
session.removeAttribute("loginUserName");
}
return "logout_success";
}
@Override
public void validate() {
// TODO Auto-generated method stub
super.validate();
//用户名不能为空
if("".equals(user.getUsername().trim()))
{
this.addFieldError("usernameError", "用户名不能为空！");
}
if(user.getPassword().length()<6)
{
this.addFieldError("passwordError", "密码长度不少于6位");
}
}
@Override
public Users getModel() {
// TODO Auto-generated method stub
return this.user;
}
}
显示表单验证信息，配置：
