title: SHA-256-encrypted string as directory name
body: <p>I need to use a SHA-256-'encrypted' string as a part of a path in a filesystem (ext3, fat, ntfs, ...).</p>
  
  <p>I try to encode it with Base64, but that does not work in all cases, because the Base64-encoded string may contain '/', '\' or other invalid chars.</p>
  
  <p>Is there an (easy) way to get a file-system-safe name of an SHA-256-'encrypted'-string? I do not like to use String.replaceAll() for all possible invalid chars.</p>
  
  <p>Thanks in advance for any help</p>