code: public final SgClass create(final String implPackageName, final String implClassName,
              final SgClass superClass, final SgClass enclosingClass, final List<SgVariable> vars,
              final ImplementationFactoryListener listener, final Class<?>... intf) {
  
          return factory.create(implPackageName, implClassName, superClass, enclosingClass,
                  new VarListImplFactoryListener(vars, listener), intf);
      }
docs: Creates an implementation of the interface.
  
  @param implPackageName
  Name of the implementation package - Cannot be
  <code>null</code>.
  @param implClassName
  Name of the implementation class - Cannot be <code>null</code>
  @param superClass
  Parent class or <code>null</code>.
  @param enclosingClass
  Outer class or <code>null</code>.
  @param vars
  List of variables the implementation contains as fields -
  Cannot be <code>null</code>.
  @param listener
  Creates the bodies for all methods - Cannot be
  <code>null</code>.
  @param intf
  One or more interfaces.
  
  @return New object implementing the interface.