Sorry, I'm quite late with the answer. OpenSessionInViewFilter should be able to handle such issue providing you use the Spring SessionFactoryUtils.
--ERic On Thursday 08 June 2006 18:37, albartell wrote: > Ok, I have looked into the Tapestry+Spring+Hibernate approach prescribed by > Eric and have some questions. I am going to go into some code depth for > the archives. Note that I have visited > http://wiki.apache.org/tapestry/FrequentlyAskedQuestions/SpringHibernate > and some other threads in this list but think that I still need some final > clarification from someone who has lived it and can state that my following > scenario will be addressed by the introduction of Spring into the mix. > > Currently I use myeclipseide.com to generate my DAO POJO's from MySQL > tables. In the relationship of a Lead (parent) to Leadtag (child) it > creates the following class (note the absence of any Hibernate related > code)... > > public abstract class AbstractLead implements java.io.Serializable { > private Set leadtags = new HashSet(0); > ...code ommitted for brevity sake... > public Set getLeadtags() { > return this.leadtags; > } > public void setLeadtags(Set leadtags) { > this.leadtags = leadtags; > } > } > > > The above is "fronted" by the Lead.hbm.xml file which is as follows: > <hibernate-mapping> > <class name="com.rxs.dao.Lead" table="lead" catalog="rxsweb"> > <id name="leaduid" type="java.lang.Integer"> > <column name="leaduid" /> > <generator class="native" /> > </id> > ...code ommitted for brevity sake... > <set name="leadtags" inverse="true"> > <key> > <column name="leaduid" not-null="true" /> > </key> > <one-to-many class="com.rxs.dao.Leadtag" /> > </set> > </class> > </hibernate-mapping> > > > My hibernate.cfg.xml file is configured as follows: > <hibernate-configuration> > <session-factory> > <property > name="connection.datasource">java:comp/env/jdbc/rxscp</property> > <property > name="dialect">org.hibernate.dialect.MySQLDialect</property> > <property name="hibernate.show_sql">true</property> > > <mapping resource="com/rxs/dao/Lead.hbm.xml" /> > <mapping resource="com/rxs/dao/Leadtag.hbm.xml"></mapping> > </session-factory> > </hibernate-configuration> > > I configure the DBCP (specified above) in the /META-INF/context.xml file as > follows: > <Context path="/rxs" docBase="/rxs" > debug="0" reloadable="false"> > <Resource > name="jdbc/rxscp" > auth="Container" > type="javax.sql.DataSource" > factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory" > > maxActive="100" > maxIdle="30" > minIdle="10" > maxWait="15000" > username="myuser" > password="mypassword" > driverClassName="com.mysql.jdbc.Driver" > url="jdbc:mysql://localhost:3306/mydb" > removeAbandoned="true" > removeAbandonedTimeout="300" > validationQuery="select 1" > logAbandoned="true" > testOnBorrow="true" > testOnReturn="true" > testWhileIdle="true" > /> > </Context> > > Here is where my problem comes. I traditionally have used a Servlet filter > to initiate a single session per request as per the below DBConn.java code. > When I need to make a call to the database I simply do a > DBConn.sess().createQuery(...etc. The DBConn.sess() approach works great > for when I want to manually do a specific query that isn't facilitated by > the getters built by myeclipseide.com; but when I want to make use of > getLeadtags() to produce a list it is not using DBConn.sess() but is > instead invoking a new DB connection somehow someway (I have no idea how it > does it, I just like the work I DON'T have to do:-) > > So I guess my question is this: Given the two methods of DB access I am > doing (i.e. manual way using DBConn.sess(), and Hibernates zero code > approach) will OpenSessionInViewFilter be able to appropriately intercept > both and my lazy loading woes will be resolved? > > > public class DBConn implements Filter { > private static Logger logger = Logger.getLogger(DBConn.class.getName()) > private static SessionFactory sessionFactory; > private static ThreadLocal tl = new ThreadLocal(); > > static { > try { > sessionFactory = new > Configuration().configure().buildSessionFactory(); > } catch (HibernateException e) { > System.err.println("Initial SessionFactory creation failed." + > e); > e.printStackTrace(); > throw new ExceptionInInitializerError(e); > } > } > public void doFilter(ServletRequest request, ServletResponse response, > FilterChain chain) > throws IOException, ServletException { > try { > chain.doFilter(request, response); > } finally { > Session s = (Session) tl.get(); > if (s != null) { > try { > s.flush(); > s.close(); > } catch (HibernateException e) { > e.printStackTrace(); > } > tl.set(null); > } > } > } > public static Session sess() { > Session s = (Session) tl.get(); > if (s == null || !s.isOpen()) { > try { > s = sessionFactory.openSession(); > } catch (HibernateException e) { > e.printStackTrace(); > } > tl.set(s); > } > return s; > } > public void init(FilterConfig filterConfig) throws ServletException { > } > public void destroy() { > } > } > > Aaron Bartell > http://mowyourlawn.com/blog > > -----Original Message----- > From: Eric Fesler [mailto:[EMAIL PROTECTED] > Sent: Thursday, June 08, 2006 8:26 AM > To: Tapestry users > Subject: Re: @For within a @contrib:Table > > Hi, > > I already had this issue in the past. It was due to the fact that the > leadtagtype (or equivalent) method was called on the leadtag bean after the > hibernate session was closed. > > There are two ways to solve the issue. > 1°) Do not use lazy loading for the leadtagtype association > 2°) Use the OpenSessionInViewFilter of the Spring framework. This filter > opens the session only once per request and close it at the end of the > request. > > --ERic > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] -- Eric Fesler Technical Director ------------------------------------------------------------------- Audaxis S.A. 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