code: @Override
  	public String toHexString(boolean with0xPrefix) {  
  		String result;
  		if(hasNoStringCache() || (result = (with0xPrefix ? stringCache.hexStringPrefixed : stringCache.hexString)) == null) {
  			result = toHexString(with0xPrefix, null);
  			if(with0xPrefix) {
  				stringCache.hexStringPrefixed = result;
  			} else {
  				stringCache.hexString = result;
  			}
  		}
  		return result;
  	}
docs: Writes this address as a single hexadecimal value with always the exact same number of characters, with or without a preceding 0x prefix.