docs: @Override
      void findReferencedClassNames(final Set<String> classNameListOut) {
          if (classBound != null) {
              classBound.findReferencedClassNames(classNameListOut);
          }
          for (final ReferenceTypeSignature typeSignature : interfaceBounds) {
              typeSignature.findReferencedClassNames(classNameListOut);
          }
      }