code: public void assertNonExisting(CryptoPath cleartextPath) throws FileAlreadyExistsException, IOException {
  		try {
  			CiphertextFileType type = getCiphertextFileType(cleartextPath);
  			throw new FileAlreadyExistsException(cleartextPath.toString(), null, "For this path there is already a " + type.name());
  		} catch (NoSuchFileException e) {
  			// good!
  		}
  	}
docs: Verifies that no node exists for the given path. Otherwise a {@link FileAlreadyExistsException} will be thrown.
  
  @param cleartextPath A path
  @throws FileAlreadyExistsException If the node exists
  @throws IOException                If any I/O error occurs while attempting to resolve the ciphertext path