Exception: Entity must be managed to call remove

Question

hello guys, I'm still here. I have another problem with toplink and jpa.
I have the following method:
+private void eliminaCliente(Evento evento) {+
+ Cliente cliente = this.finestraCliente.getCliente();+
+ ClienteFacade facade = new ClienteFacade();+
+ try {+
+ facade.getEm().getTransaction().begin();+
+ facade.getEm().merge(cliente);+
+ facade.getEm().remove(cliente);+
+ facade.getEm().flush();+
+ } catch(PersistenceException e) {+
+ String messaggio;+
+ if(e.getCause() instanceof ConstraintViolationException) { // vincolo di integrità violato+
+ messaggio = "Impossibile completare l'operazione a causa della violazione di un vincolo di integrità:\n---> ";+
+ messaggio += e.getCause().getCause().getMessage();+
+ } else // errore generico+
+ messaggio = e.getMessage();+
+ apriFinestraMessaggio(evento, e.getMessage());+
+ } finally {+
+ facade.getEm().close();+
+ }+
+ }+
Its duty is to get an entity from the gui, and remove it. The problem is that on the line in wich I call the remove method, it generate this exception:
java.lang.IllegalArgumentException: Entity must be managed to call remove: Abba Pino, try merging the detached and try the remove again.
why?

Answer 1

The call to merge will return a managed instance that you can use in your remove call.
private void eliminaCliente(Evento evento) {
        Cliente cliente = this.finestraCliente.getCliente();
        ClienteFacade facade = new ClienteFacade();
        try {
            facade.getEm().getTransaction().begin();
            Cliente managedCliente = facade.getEm().merge(cliente);
            facade.getEm().remove(managedCliente);
        ...Doug