public class Hex {

// Source:

// https://stackoverflow.com/questions/9655181/how-to-convert-a-byte-array-to-a-hex-string-in-java

/* s must be an even-length string. */

public static byte[] hexStringToByteArray(String s) {

int len = s.length();

byte[] data = new byte[len / 2];

for (int i = 0; i < len; i += 2) {

data[i / 2] =

(byte) ((Character.digit(s.charAt(i), 16) << 4) + Character.digit(s.charAt(i + 1), 16));

}

return data;

}

private static final char[] HEX_ARRAY = "0123456789abcdef".toCharArray();

public static String bytesToHex(byte[] bytes) {

char[] hexChars = new char[bytes.length * 2];

for (int j = 0; j < bytes.length; j++) {

int v = bytes[j] & 0xFF;

hexChars[j * 2] = HEX_ARRAY[v >>> 4];

hexChars[j * 2 + 1] = HEX_ARRAY[v & 0x0F];

}

return new String(hexChars);

}

}