javaweb loginSystem 总结

包的结构：dao,dao.impl,service,service.impl,util,test,web.controller,web.formbean,web.UI 

用到的东西： 

hibernate3.6,jstl,beanutils(其中jstl和beanutils貌似eclipse自带) 

流程： 

几个要点： 

1. web.UI包存在的原因是为了保护jsp，将jsp放到WEB-INF目录下，不能直接访问，这时用servlet进行跳转 

2. 登录成功后进行重定向到首页，因此将用户放到session域中，而在注销的时候getSession（false)，且不要忘了删除 

3. 等待几秒刷新使用http头进行模拟 <meta http-equiv="refresh" content="3; url=xxx"> 

4. 在主页使用jstl的c:if标签进行判断，如果有用户，显示hello，否则显示登录或注册提示，判断为空用empty 

5. 验证写在formbean里，错误放到formbean的一个hashmap里，并且出错后放到request里的是整个formbean 

 

一些代码类似于模版代码： 

1. HibernateUtil

   public class HibernateUtil { 
   
   private static final SessionFactory sessionFactory=buildSessionFactory(); 
   
   private static SessionFactory buildSessionFactory(){ 
   
   try{ 
   
   return new Configuration().configure().buildSessionFactory(); 
   
   }catch(Throwable ex){ 
   
   System.err.println("Initial SessionFactory creation failed." + ex); 
   
               throw new ExceptionInInitializerError(ex); 
   
   } 
   
   } 
   
   public static SessionFactory getSessionFactory(){ 
   
   return sessionFactory; 
   
   } 
   
   } 

2. md5加密

       public static String md5(String src){
           try {
               MessageDigest md=MessageDigest.getInstance("md5");
               byte[] md5=md.digest(src.getBytes());
               BASE64Encoder encoder=new BASE64Encoder();
               return encoder.encode(md5);
           } catch (NoSuchAlgorithmException e) {
               e.printStackTrace();
               throw new RuntimeException(e);
           }
       }

3. request2bean,copybean

   public static <T> T request2bean(HttpServletRequest request,Class<T> type){
           Enumeration names=request.getParameterNames();
           T bean;
           try {
               bean = type.newInstance();
           } catch (Exception e) {
               e.printStackTrace();
               throw new RuntimeException(e);
           } 
           HashMap map=new HashMap();
           while(names.hasMoreElements()){
               String name=(String) names.nextElement();
               map.put(name, request.getParameter(name));
           }
           try {
               BeanUtils.populate(bean, map);
               return bean;
           } catch (Exception e) {
               e.printStackTrace();
               throw new RuntimeException(e);
           }
               
       }
       
       public static void copyBean(Object dest,Object src){
           //注册自定义对象转换类
           ConvertUtils.register(new Converter(){
   
               @Override
               public Object convert(Class type, Object value) {
                   SimpleDateFormat df=new SimpleDateFormat("yyyy-MM-dd");
                   String dateStr=(String) value;
                   if(!StringUtils.isNullOrEmpty(dateStr)){
                       try {
                           return df.parse(dateStr);
                       } catch (ParseException e) {
                           e.printStackTrace();
                       }
                   }
                   return null;
               }
               
           }, Date.class);
           
           try {
               BeanUtils.copyProperties(dest, src);
           } catch (Exception e) {
               e.printStackTrace();
               throw new RuntimeException(e);
           } 
           
       }

4. hibernate的save

       public void addUser(User user) {
           Session session=null;
           Transaction ts=null;
           try {
               session = sf.openSession();
               ts = session.beginTransaction();
               ts.begin();
               session.save(user);
               Query query=session.createQuery("from User where username=? and password=?");
               query.setParameter(0, username);
               query.setParameter(1, password);
               List<User> result=query.list();
               ts.commit();
           } catch (Exception e) {
               if(ts!=null){
                   ts.rollback();
               }
               e.printStackTrace();
               throw new RuntimeException("failed to add user.");
           }finally{
               if(session!=null && session.isOpen()){
                   session.close();
               }
           }
       }

5. hibernate配置文件和映射文件

   <?xml version='1.0' encoding='utf-8'?>
   <!DOCTYPE hibernate-configuration PUBLIC
           "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
           "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
           
   <hibernate-configuration>
   
       <session-factory>
       
           <!-- Database connection settings -->
           <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
           <property name="connection.url">jdbc:mysql://localhost:3306/javaweb</property>
           <property name="connection.username">root</property>
           <property name="connection.password">123456</property>
           
           <!-- JDBC connection pool (use the built-in) -->
           <property name="connection.pool_size">1</property>
   
           <!-- SQL dialect -->
           <property name="dialect">org.hibernate.dialect.HSQLDialect</property>
   
           <!-- Enable Hibernate's automatic session context management -->
           <property name="current_session_context_class">thread</property>
   
           <!-- Disable the second-level cache  -->
           <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
   
           <!-- Echo all executed SQL to stdout -->
           <property name="show_sql">true</property>
   
           <!-- Drop and re-create the database schema on startup -->
           <property name="hbm2ddl.auto">create</property>
           
           <mapping resource="com/libin/domain/User.hbm.xml"/>
       </session-factory>
       
   </hibernate-configuration>

   <?xml version='1.0' encoding='utf-8'?>
   <!DOCTYPE hibernate-mapping PUBLIC
           "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
           "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
   
   <hibernate-mapping package="com.libin.domain">
   
       <class name="User" table="user">
       
           <id name="id" column="user_id">
               <generator class="uuid" />
           </id>
           
           <property name="username">
               <column name="username" not-null="true" />
           </property>
           
           <property name="password">
               <column name="password" not-null="true" />
           </property>
           
           <property name="email">
               <column name="email" length="30" not-null="true" />
           </property>
           
           <property name="birthday" type="date" />
           
       </class>
   
   </hibernate-mapping>