@Override
  public boolean equals(Object obj) {
    if (obj instanceof DirectoryEntry) {
      DirectoryEntry other = (DirectoryEntry) obj;
      return directory.equals(other.directory)
          && name.equals(other.name)
          && Objects.equals(file, other.file);
    }
    return false;
  }
Returns the file this entry links to or {@code null} if the file does not exist
jimfs/src/main/java/com/google/common/jimfs/DirectoryEntry.java