Styjun

I am definitely missing something here. My problem is this:
I get the following exception:

java.lang.IllegalStateException: During synchronization a new object was found through a relationship that was not marked cascade PERSIST: entity.Book[ bookId=null ]

when trying to run a named query though the EntityManager.

I have a RESTful service oriented Java web app, which comprises a series of xxxFacadeREST files (e.g. BookFacadeREST), each containing the services (create, edit, remove, find etc) for the given xxx entity (e.g. Book). I am trying to retrieve an entity while inside a create service/method for another entity (e.g. try to retrieve a BookType while inside BookFacadeREST.create()). My usual approach to this is to use the EntityManager, being initialised by my PersistenceContext, and execute a named query, like this:

BookType bt = em.createNamedQuery("BookType.findByTypeId", BookType.class).setParameter(....) etc etc

However, as already mentioned, I get an IllegalStateException when doing this. Instead, if I try to retrieve the BookType through calling its own FacadeREST's find() method, everything works. Now, what makes this strange is that I use named queries all over the place without problems. I even use one earlier in the same create method to retrieve another entity, and it works. So something must be amiss concerning the way Book and BookType are set up (I am assuming).

public class BookFacadeREST extends AbstractFacade<Book> 
 @EJB
 private BookTypeFacadeREST bookTypeFacadeREST;
 @PersistenceContext(unitName = "bla bla")
 private EntityManager em;

 @POST
 public Book create(Book entity) 
 // works fine
 if (entity.getLibraryId() != null) 
 lib = em.createNamedQuery("Library.findByLibraryId", Library.class).setParameter("libraryId", entity.getLibraryId().getLibraryId()).getSingleResult();
 ....
 

 if (entity.getTypeId() != null) 
 ....
 else 
 BookType defaultType = bookTypeFacadeREST.find(new Long(1L));
 // For some reason retrieving the book type using em.createNamedQuery DOES NOT WORK !!!
 //BookType defaultType = em.createNamedQuery("BookType.findByTypeId", BookType.class).setParameter("typeId", new Long(1L)).getSingleResult();
 entity.setTypeId(defaultType);
 defaultType.addBook(entity);

 
 .....
 return super.create(entity);
 


@Entity
@Multitenant(value = TABLE_PER_TENANT)
@TenantTableDiscriminator(type = SCHEMA, contextProperty = MULTITENANT_PROPERTY_DEFAULT)
@Table(name = "book")
@XmlRootElement
public class Book implements Serializable 

 private static final long serialVersionUID = 1L;
 @Id
 @GeneratedValue(strategy = GenerationType.IDENTITY)
 @Basic(optional = false)
 @Column(name = "bookId")
 private Long bookId;
 @JoinColumn(name = "typeId", referencedColumnName = "typeId")
 @ManyToOne(optional = false)
 @NotNull
 private BookType typeId;
 @JoinColumn(name = "libraryId", referencedColumnName = "libraryId")
 @ManyToOne(optional = false)
 private Library libraryId;

 .....


@Entity
@Multitenant(value = TABLE_PER_TENANT)
@TenantTableDiscriminator(type = SCHEMA, contextProperty = MULTITENANT_PROPERTY_DEFAULT)
@Table(name = "book_type")
@XmlRootElement
@NamedQueries(
 @NamedQuery(name = "BookType.findByTypeId", query = "SELECT b FROM BookType b WHERE b.typeId = :typeId"))
public class BookType implements Serializable 

 private static final long serialVersionUID = 1L;
 @Id
 @GeneratedValue(strategy = GenerationType.IDENTITY)
 @Basic(optional = false)
 @Column(name = "typeId")
 private Long typeId;
 @Basic(optional = false)
 @NotNull
 @Size(min = 1, max = 50)
 @Column(name = "name")
 private String name;
 @OneToMany(cascade = CascadeType.ALL, mappedBy = "typeId")
 private List<Book> bookList;

 ....

Why is it that retrieving through the EntityManager fails, while calling the find service (GET) for a specific BookType id works, bearing in mind that the

lib = em.createNamedQuery("Library.findByLibraryId", Library.class)....

also works.

Thank you all in advance.