the code in Converter.java:

if (targetType instanceof TypeVariable) {
         TypeVariable<?> typeVariable = (TypeVariable<?>)targetType;
         if (typeVariable.getGenericDeclaration() instanceof Type)
         targetType = (Type)typeVariable.getGenericDeclaration();
}

the problem is "typeVariable.getGenericDeclaration()", this method returns the GenericDeclaration object representing the generic declaration declared this type variable. it's not true.

I think use "typeVariable.getBounds()" ,it's returns an array of Types representing the upper bound(s) of this type variable.

example entity code:

@Entity
@Inheritance(strategy = InheritanceType.JOINED)
public abstract class Application<T extends ApplicationMeta> extends
AbstractEntity {

private static final long serialVersionUID = -5063254461237352117L;

private T applicationMeta;

@ManyToOne(fetch = FetchType.LAZY, targetEntity = ApplicationMeta.class)
@JoinColumn(name = "META_ID", nullable = false)
public T getApplicationMeta() {
return applicationMeta;
}

public void setApplicationMeta(T meta) {
this.applicationMeta = meta;
}
}

getGenericDeclaration returns Application,getBounds returns [ApplicationMeta],ApplicationMeta is expected.