@Table(name = "DFIP_PROJECT_VERSION")
@Entity
@Inheritance(strategy = InheritanceType.JOINED)
public abstract class AbstractProjectVersion {

	@Id @GeneratedValue(strategy = GenerationType.AUTO)
	@Column(name = "PROJECT_VERSION_OID")
        Long oid;
	
	@Column(name = "PROJ_VSN_EFF_FROM_DTM")
	Timestamp effFromDtm;
	
	@Column(name = "PROJ_VSN_EFF_TO_DTM")
	Timestamp effToDtm;
	
	
	public void makeCurrent() {
		setEffFromDtm( new Timestamp(System.currentTimeMillis()) );
	}

	public void expire(){
		setEffToDtm( new Timestamp(System.currentTimeMillis()) );
	}

}

@Table(name = "DFIP_APPLN_PROJ_VERSION")
@Entity
public class ApplicationProjectVersion extends AbstractProjectVersion {

	@ManyToOne
	@JoinColumn(name = "APPLICATION_OID", nullable = false)
	Application application;

	@Column(name = "APPLICATION_VERSION_NUM", nullable = false)
	Integer versionNumber = 1; 
	
	public ApplicationProjectVersion() {
		makeCurrent();
	}


	public ApplicationProjectVersion(Application application) {
		this();
		this.application = application;
	}
}

@Table(name = "DFIP_APPLICATION")
@Entity
public class Application {
	@Id @GeneratedValue(strategy = GenerationType.AUTO)
	@Column(name = "APPLICATION_OID")
    Long oid;
	
	// This collection consists of entities that are mapped with InheritanceType.JOINED strategy.
	// This is where the problem is.
	//
	@OneToMany(mappedBy="application", orphanRemoval = true, fetch = FetchType.EAGER)
	@Cascade({SAVE_UPDATE, DELETE, MERGE})
	@Fetch(FetchMode.SELECT)
	@Where(clause = "PROJ_VSN_EFF_TO_DTM is null")   // <= THIS IS THE PROBLEM
	List<ApplicationProjectVersion> applicationVersions = new ArrayList<>();
	
	public void addApplicationProjectVersion(ApplicationProjectVersion apv) {
		apv.setApplication(this);
		
		if ( !applicationVersions.isEmpty() ) {
			apv.setVersionNumber(applicationVersions.get(applicationVersions.size() - 1).getVersionNumber() + 1);
		}
		
		applicationVersions.add(apv);
	}
}