public static @Nullable PsiImplicitClass getImplicitClassFor(@NotNull PsiElement file) {
    if (file instanceof PsiJavaFile) {
      final PsiJavaFile javaFile = (PsiJavaFile)file;
      PsiClass[] classes = javaFile.getClasses();
      if (classes.length == 1 && classes[0] instanceof PsiImplicitClass) {
        return (PsiImplicitClass)classes[0];
      }
    }
    return null;
  }
public static @Nullable PsiImplicitClass getImplicitClassFor(@NotNull PsiElement file)