最近这一个阶段一直在研究hibernate,总感觉好象什么地方特别扭,研究一段时间,看了论坛上的各位大虾和小虾写的例子,自己也写了一个,在这里贴出来,希望得到大家的批评指正,特别是在架构上如何设计给些意见,因为对照关系如一对一,一对多的实现论坛的例子已经很清楚了.

开发环境:
struts 1.1
tomcat4.1.24
hibernate2.1.2
oracle 8.16

表﹕company

id      公司ID
company_name    公司名稱

配置就不說了﹐

po:company.java

public class Company {
	private String id;
	private String companyname;
	
	public String getId();{
		return id;
	}
	public String getCompanyname();{
		return companyname;
	}
	
	public void setId(String id);{
		this.id=id;
	}
	public void setCompanyname(String companyname);{
		this.companyname=companyname;
	}
}

company持久類對應的映射文件﹕
company.hbm.xml

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
    <class name="com.foxconn.hibernate.po.Company" table="company" dynamic-update="false">
        <id name="id" column="id" type="string" unsaved-value="any" >
            <generator class="assigned">
            </generator>
        </id>
        <property name="companyname" type="string" update="true" insert="true" column="company_name"/>
    </class>
</hibernate-mapping>

配置文件hibernate.cfg.xml

<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration D

TD//EN" "http://hibernate.sourceforge.net/hibernate-configuration-2.0.dtd">

<hibernate-configuration>

<session-factory>

<property name="connection.datasource">java:comp/env/jdbc/fox221</property>

<property name="show_sql">false</property>

<property name="dialect">net.sf.hibernate.dialect.OracleDialect</property>

<property name="jdbc.fetch_size">50</property>

<property name="jdbc.batch_size">30</property>

<!-- Mapping files -->

<mapping resource="/hbm/Company.hbm.xml"/>

</session-factory>

</hibernate-configuration>

提供session的类HebernateSessionFactory(利用Thread管理session)

public class HibernateSessionFactory { 
    public static final ThreadLocal session = new ThreadLocal();; 
    private static SessionFactory sessionFactory;
 
     static {
        try {
            sessionFactory =
                    new Configuration();.configure();.buildSessionFactory();;
        } catch (HibernateException ex); {
            throw new RuntimeException(
                    "Exception building SessionFactory: " + ex.getMessage();,ex);;
        }
    }

    public static Session currentSession(); throws HibernateException{ 
        	Session s = (Session); session.get();; 
        	if (s == null); { 
            	s =  sessionFactory.openSession();; 
            	session.set(s);; 
        	} 
        	return s; 
    } 
    public static void closeSession(); throws HibernateException{ 
        Session s = (Session); session.get();; 
        session.set(null);; 
        if (s != null); s.close();; 
    } 
    
} 

封装CRUD操作的类(我觉的此类应该设置为abstract类)

public class HibernateUtil { 
    public static void add( Object object );throws HibernateException{        Session s = HibernateSessionFactory.currentSession();; 
        s.save( object );; 
        s.flush();;
        s.beginTransaction();.commit();;
    } 
    public static void update( Object object ); throws HibernateException { 
        Session s = HibernateSessionFactory.currentSession();; 
        s.beginTransaction();;
        s.saveOrUpdate( object );; 
        s.flush();; 
    } 
    public static void remove(Class clazz, String id); throws HibernateException { 
        Session s = HibernateSessionFactory.currentSession();; 
        s.beginTransaction();;
        Object object = s.load(clazz, id);; 
        s.delete( object );; 
        s.flush();; 
    } 
    public static Object findById( Class clazz, String id ); throws HibernateException { 
        Object obj = null; 
        Session s = HibernateSessionFactory.currentSession();; 
        obj = s.load( clazz, id );; 
        s.flush();; 
        return obj; 
    } 
} 

在filter中关闭session,这个filter还可以用于字符集转换.
HibernateFilter.java  

public class HibernateFilter implements Filter {
   private String encode = "big5";
   
    public void init(FilterConfig config); {
        this.encode = config.getInitParameter("encode");;
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain); {
        try{
            request.setCharacterEncoding(this.encode);;
            response.setContentType("text/html;charset="+encode);;
            chain.doFilter(request, response);;
        }
        catch(Exception e);{
            if(!(e instanceof java.net.SocketException););{
                if(request instanceof HttpServletRequest);
                    Logger.getLogger(this.getClass(););.error("error request uri:"+((HttpServletRequest);request);.getRequestURI(););;
                Logger.getLogger(this.getClass(););.error(e);;
            }
        }finally{
        	try{
        		HibernateSessionFactory.closeSession();;
        	}catch(Exception ex);{
        		System.out.println("Error in closing session");;
        	}	
        }
    }

    public void destroy(); {
    }
}

以上是hibernate相关部分.