I'm trying to build a db schema with Oracle and JPA. I'm new to JPA, I always worked directly with sql.
What I need to do create are two tables: the first one containing the current VOIP calls and another with the history of those calls. The two tables are identical.
In JPA I wrote this:

```
@Entity
@Table(name = "voip_currentCalls")
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
public class VoipCurrentCall implements Serializable {

    private static final long serialVersionUID = 1L;
    protected CompositeID id;
    protected Timestamp startTime;
    protected Timestamp endTime;
    protected String calledNumber;
    protected String callingNumber;    
    protected Person contact;
    protected CallSource source;
    protected CallStatus status;
    protected CallType type;
    protected CallStage stage;

@Entity
@Table(name = "voip_historyCalls")
public class VoipHistoryCall extends VoipCurrentCall implements Serializable {
...

```

As you can see the second table has no other fields, but it is simply and extends of the first.
when I try to cast the VoipCurrentCall to VoipHistoryCall, I obtain java.lang.ClassCastException: VoipCurrentCall cannot be cast to VoipHistoryCall.

Have you any suggestions? I'm probably missing something.
Thank to all in advance!