code: public static byte[] decodeFromString(String src) {
  		assertSupported();
  		if (src == null) {
  			return null;
  		}
  		if (src.length() == 0) {
  			return new byte[0];
  		}
  		return delegate.decode(src.getBytes(DEFAULT_CHARSET));
  	}
docs: Base64-decode the given byte array from an UTF-8 String.
  @param src the encoded UTF-8 String (may be {@code null})
  @return the original byte array (or {@code null} if the input was {@code null})
  @throws IllegalStateException if Base64 encoding is not supported,
  i.e. neither Java 8 nor Apache Commons Codec is present at runtime