@Nullable
  private static PsiType getRealType(PsiMethod method) {
    final PsiElement navigationElement = method.getNavigationElement();
    if (navigationElement instanceof PsiMethod) {
      final PsiParameter[] parameters = ((PsiMethod)navigationElement).getParameterList().getParameters();
      if (parameters.length != 0) {
        return TypeConversionUtil.erasure(parameters[0].getType());
      }
    }
    final PsiClass containingClass = method.getContainingClass();
    if (containingClass == null) return null;
    return JavaPsiFacade.getElementFactory(method.getProject()).createType(containingClass);
  }
@Nullable
  private static PsiType getRealType(PsiMethod method)