title: Why my @MappedSuperClass doesn't work?
body: <p>I have the following @MappedSuperClass and @Entity :</p>
  
  <pre><code>@MappedSuperclass 
  public class SuperClass implements Serializable {....}
  
  @Entity
  @Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
  @Table(name = "TABLE1")
  public class Table1 extends SuperClass implements Serializable {...}
  
  @Entity
  @Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
  @Table(name = "TABLE2")
  public class Table2 extends SuperClass implements Serializable {...}
  </code></pre>
  
  <p>In the database, both table have the same columns so all my attribute are in the SuperClass :</p>
  
  <pre><code>@Id
  private String attr1;
  
  @Id
  private String attr2;
  
  @Column(name="DATA")
  private String data;
  
  // getters and setters
  </code></pre>
  
  <p>But when I try to execute a query with one of the @entity (table1 or table2), I get an OpenJPA ERROR :</p>
  
  <pre><code>Error pre-processing class table1 with weblogic.deployment.PersistenceUnitInfoImpl$ClassPreProcessorImpl@205c54b'
  &lt;openjpa-1.1.0-r422266:657916 fatal user error&gt; 
  org.apache.openjpa.util.MetaDataException: Type "class SuperClass" with application identity and no superclass does not declare an id class.  
  This type is not eligible for builtin identity, so it must declare an id class.
  </code></pre>
  
  <p>I don't understand why the attribute @Id are not found in the @Entity Class.</p>
  
  <p>If anyone have any ideas, feel free to help me :)</p>
  
  <p>Regards,</p>
  
  <p>Cytemax</p>