code: public static boolean isClassClassNodeWrappingConcreteType(ClassNode classNode) {
          GenericsType[] genericsTypes = classNode.getGenericsTypes();
          return ClassHelper.CLASS_Type.equals(classNode)
                  && classNode.isUsingGenerics()
                  && genericsTypes!=null
                  && !genericsTypes[0].isPlaceholder()
                  && !genericsTypes[0].isWildcard();
      }
docs: Returns true if the class node represents a the class node for the Class class
  and if the parametrized type is a neither a placeholder or a wildcard. For example,
  the class node Class&lt;Foo&gt; where Foo is a class would return true, but the class
  node for Class&lt;?&gt; would return false.
  @param classNode a class node to be tested
  @return true if it is the class node for Class and its generic type is a real class