code: public static URI getRootURI(final VirtualFile file) throws URISyntaxException {
          return VFS.getMount(file).getFileSystem().getRootURI();
      }
docs: Get the physical root URL of the filesystem of a virtual file.  This URI is suitable for conversion to a class loader's
  code source URL or in similar situations where only standard URL types ({@code jar} and {@code file}) are supported.
  
  @param file the virtual file
  @return the root URI
  @throws URISyntaxException if the URI is not valid