Hi, I have met a problem using EntityHome with Seam, I have found a solution by modifying a setter but I want to be sure it is the proper way to do it. In order to implement a function “Post a topic in a forum”, I have created 2 EntityBeans : Subject and Message. There is a oneToMany (two-way association) relation between Subjet and Message. public class Subject implements Serializable { ... private List associatedMessages = new LinkedList(); @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "ownerSubject") @OrderBy(value = "messageId ASC") public List getAssociatedMessages() { return associatedMessages; } public void setAssociatedMessages(List associatedMessages) { this.associatedMessages = associatedMessages; } ... } public class Message implements Serializable { ... private Subject ownerSubject; @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL) @JoinColumn(name = "OWNER_SUBJECT_ID") public Subject getOwnerSubject() { return ownerSubject; } public void setOwnerSubject(Subject ownerSubject) { this.ownerSubject = ownerSubject; } } When a Subject instance is created, at the same time a 1st Message instance is created too and added to the List the subject, as shown in createSubject2() of the SessionBean SubjectHome @Name("subjectHome") public class SubjectHome extends EntityHome { ... @In(required=false) MessageHome messageHome; public void createSubject2() { this.messageHome.getInstance().setOwnerSubject(this.getInstance()); this.messageHome.persist(); this.logger.info("NUMBER OF ASSOCIATED MESSAGES : " + this.instance.getAssociatedMessages().size()); } ... } I've checked: 2 instances were successfully persisted, so in the datebase, 2 new rows were inserted in Subject table and Message table with no problem. However in the console : INFO [SubjectHome] NUMBER OF ASSOCIATED MESSAGES : 0 And when I navigate to the webpage which is used to show something of corresponding message of a Subject i met such error: CODE: #{subject.associatedMessages.get(0).submitTime} ERROR: /subjectList.xhtml: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0 So I add a line in the Setter in my Message EntityBean : public void setOwnerSubject(Subject ownerSubject) { this.ownerSubject = ownerSubject; this.ownerSubject.getAssociatedMessages().add(this); } This solves our problem, the new message is well in the subject List attribute without having to open a new session. I just want to verify if it's ok to add additional line in Setter of EntityBean, just like what I did ? Thank you! Regards Li View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4156236#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...