Java convert Base64 to Hex String [duplicate]

Answer 1

Since you are already using Apache Common Codec:

String guid = "YxRfXk827kPgkmMUX15PNg==";
byte[] decoded = Base64.decodeBase64(guid);
String hexString = Hex.encodeHexString(decoded);
System.out.println(hexString);

Using standard Java libraries:

String guid = "YxRfXk827kPgkmMUX15PNg==";
byte[] decoded = Base64.getDecoder().decode(guid);
System.out.println(String.format("%040x", new BigInteger(1, decoded)));