Another hibernate way of doing it with @Where: @Entity public class System { @Id @Column(name = “ID”) private Integer id; @OneToMany(mappedBy = “system”) @Where(clause = “active = true”) private Set<Systemproperty> systempropertys; } @Entity public class Systemproperty { @Id @Column(name = “ID”) private Integer id; @Id @Column(name = “ACTIVE”) private Integer active; }
Yes wrapper for javax.mail.Header is needed, in general you cannot persist directly arbitrary classes, especially not the ones that are not Serializable. Also they cannot be elements of list that designs relationship between entities. Value of mappedBy is name of the field that is owning side of bidirectional relationship. For a sake of example, let’s … Read more
Consider the situation where the owned entity type can also be owned by another parent entity type. Do you put foreign key references in the owned table to both parent tables? What if you have three parent types? It just doesn’t scale to large designs. A join-table decouples the join, so that the owned table … Read more
OK, after a lot of searching, I see two ways dealing with this: The first option is to retrieve an object for each column and merge it in the Java code at the resource (i.e. do the join in the code instead of having it done by the database). This would result in something like … Read more
The Manning book Java Persistence with Hibernate has an example outlining how to do this in Section 7.2. Fortunately, even if you don’t own the book, you can see a source code example of this by downloading the JPA version of the Caveat Emptor sample project (direct link here) and examining the classes Category and … Read more
This point is still quite confusing and unclear on the web, so here is the way I solved my problem. This solution is probably not the most optimized one, but it works when creating and updating a master entity. Theory Use a List instead of a Set for your one-to-many relations which should be dynamically … Read more
Instead of replacing the collection (team.setUserTeamRoles(new HashSet<UserTeamRole>());) you have to clear() the existing one. This happens because if Hibernate loads the entity (and its collections) from DB, it “manages” them, ie. tracks their changes. Generally when using Hibernate it’s better not to create any setters for collections (lists, sets). Create only the getter, and clear … Read more
Do I really have to do sth. like this? That is one strategy, yes. On bi-directional relationships there is an “owning” and a “non-owning” side of the relationship. Because the owning side in your case is on Child, you need to set the relationship there for it to be persisted. The owning side is usually … Read more
Unfortunately there is no sync method for one-to-many relations. It’s pretty simple to do it by yourself. At least if you don’t have any foreign key referencing links. Because then you can simple delete the rows and insert them all again. $links = array( new Link(), new Link() ); $post->links()->delete(); $post->links()->saveMany($links); If you really need … Read more