Can someone tell me why i am getting the following exception?
i am getting the session...doing some transactions....and then closing the session..then why is session getting closed in the middle?
has it got anything to do with find method?

I am very new to this Hibernate...and searched in the forums also...but could not really get what i wanted...

Thanks,
SSSS.


Hibernate version:2

<class name="com.sat.helper.PrivilegeDB" table="PRIVILEGE">
<id name="id" type="string" column="PRIVILEGE_ID">
<generator class="uuid.hex"/>
</id>
<property name="name" column="PRIVILEGE_NAME"/>
<set name="roles" table="ROLE_PRIV_MAP" inverse="true" lazy="true" >
<key column="PRIVILEGE_ID"/>
<one-to-many class="com.sat.helper.PrivRoleMapDB"/>
</set>
</class>
<class name="com.sat.helper.PrivRoleMapDB" table="ROLE_PRIV_MAP">
<composite-id>
<key-many-to-one name="privilege" class="com.sat.helper.PrivilegeDB" column="PRIVILEGE_ID" />
<key-many-to-one name="role" class="com.sat.helper.RoleDB" column="ROLE_ID" />
</composite-id>
</class>

<class name="com.sat.helper.RoleDB" table="ROLE">
<id name="id" type="string" column="ROLE_ID">
<generator class="uuid.hex"/>
</id>
<property name="lastUpdateDate" type="calendar" column="LAST_UPDATE_INFO"/>
<property name="name" column="ROLE_NAME"/>
<set name="privRoleMaps" table="ROLE_PRIV_MAP" inverse="true" lazy="true" >
<key column="ROLE_ID"/>
<one-to-many class="com.sat.helper.PrivRoleMapDB"/>
</set>
</class>


Session session = getSession();
Transaction trans = session.beginTransaction();
List rolesList = getHibernateTemplate().find("from RoleDB");
if(rolesList != null){
int listSize = rolesList.size();
for(int i=0;i<listSize;i++){
RoleDB roleDB = (RoleDB) rolesList.get(i);
System.out.println("role id and name are " + roleDB.getId() + "and " + roleDB.getName());
Set privs = roleDB.getPrivRoleMaps();
if(privs != null) {
Iterator iter = privs.iterator();
while(iter.hasNext()){
PrivRoleMapDB p = (PrivRoleMapDB) iter.next();
System.out.println("priv id and name are " + p.getPrivilege().getId() + "and " + p.getPrivilege().getName());
}
} else{
System.out.println("privs are null for this role");
}
}
}
session.flush();
trans.commit();
session.close();


SEVERE: Failed to lazily initialize a collection - no session or session was cl
sed
net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a col
ection - no session or session was closed
at net.sf.hibernate.collection.PersistentCollection.initialize(Persiste
tCollection.java:209)
at net.sf.hibernate.collection.PersistentCollection.read(PersistentColl
ction.java:71)
at net.sf.hibernate.collection.Set.iterator(Set.java:130)
at com.sat.dao.DAO.getRoles(DAO.java:263)
at com.sat.FacadeImpl.getRoles(FacadeImpl.java:136)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.framework.AopProxyUtils.invokeJoinpointUsing
eflection(AopProxyUtils.java:59)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynam
cAopProxy.java:138)
at $Proxy0.getRoles(Unknown Source)
at com.sat.FacadeImpl.main(FacadeImpl.java:152)
net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a col
ection - no session or session was closed
at net.sf.hibernate.collection.PersistentCollection.initialize(Persiste
tCollection.java:209)
at net.sf.hibernate.collection.PersistentCollection.read(PersistentColl
ction.java:71)
at net.sf.hibernate.collection.Set.iterator(Set.java:130)
at com.sat.dao.DAO.getRoles(DAO.java:263)
at com.sat.FacadeImpl.getRoles(FacadeImpl.java:136)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.framework.AopProxyUtils.invokeJoinpointUsing
eflection(AopProxyUtils.java:59)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynam
cAopProxy.java:138)
at $Proxy0.getRoles(Unknown Source)
at com.sat.FacadeImpl.main(FacadeImpl.java:152)
java.lang.NullPointerException
at com.sat.FacadeImpl.main(FacadeImpl.java:153)

Name and version of the database you are using: DB2 7.1

The generated SQL (show_sql=true):

Debug level Hibernate log excerpt:

i don't know exactly, because you haven't posted the hole relevant code ... but it seems for me, that your session-handling is broken ...

gtx
curio

but that is all the code that i wrote..

DAO extends HibernateDaoSupport
public Role[] getRoles() {

Session session = getSession();
Transaction trans = session.beginTransaction();
List rolesList = getHibernateTemplate().find("from RoleDB");
if(rolesList != null){
int listSize = rolesList.size();
for(int i=0;i<listSize;i++){
RoleDB roleDB = (RoleDB) rolesList.get(i);
System.out.println("role id and name are " + roleDB.getId() + "and " + roleDB.getName());
Set privs = roleDB.getPrivRoleMaps();
if(privs != null) {
Iterator iter = privs.iterator();
while(iter.hasNext()){
PrivRoleMapDB p = (PrivRoleMapDB) iter.next();
System.out.println("priv id and name are " + p.getPrivilege().getId() + "and " + p.getPrivilege().getName());
}
} else{
System.out.println("privs are null for this role");
}
}
}
session.flush();
trans.commit();
session.close();


}


i am calling this method from a class which has main method...that is all what i am doing...am i missing something????

Thanks,
SSSS

well if that's all the code you've written ...

where comes the and methods from? ;-)

Check your sources if you're using one session for one Unit of Work ...

gtx
curio

My DAO is extending HibernateDaoSupport...so i can use
getHibernateTemplate() and getSession() methods...

i didn't really understand what was wrong with that...

what is meant a single unit of work?

here i am asking for a single select query...

where am i breaking the rules??

Thanks,
SSSS.