* example, this can be used to reject wildcards or type variables contained in a type as in:
 *
 * <pre>{@code
 * new TypeVisitor() {
 *   protected void visitParameterizedType(ParameterizedType t) {
 *     visit(t.getOwnerType());
 *     visit(t.getActualTypeArguments());
 *   }
 *   protected void visitGenericArrayType(GenericArrayType t) {
 *     visit(t.getGenericComponentType());