Convert ByteArray to UUID java

The method nameUUIDFromBytes() converts a name into a UUID. Internally, it applied hashing and some black magic to turn any name (i.e. a string) into a valid UUID.

You must use the new UUID(long, long); constructor instead:

public static String getGuidFromByteArray(byte[] bytes) {
    ByteBuffer bb = ByteBuffer.wrap(bytes);
    long high = bb.getLong();
    long low = bb.getLong();
    UUID uuid = new UUID(high, low);
    return uuid.toString();
}

But since you don't need the UUID object, you can just do a hex dump:

public static String getGuidFromByteArray(byte[] bytes) {
    StringBuilder buffer = new StringBuilder();
    for(int i=0; i<bytes.length; i++) {
        buffer.append(String.format("%02x", bytes[i]));
    }
    return buffer.toString();
}

Try doing same process in reverse:

public static String getGuidFromByteArray(byte[] bytes)
{
    ByteBuffer bb = ByteBuffer.wrap(bytes);
    UUID uuid = new UUID(bb.getLong(), bb.getLong());
    return uuid.toString();
}

For both building and parsing your byte[], you really need to consider the byte order.

Try:

public static String getGuidFromByteArray(byte[] bytes) {
    ByteBuffer bb = ByteBuffer.wrap(bytes);
    UUID uuid = new UUID(bb.getLong(), bb.getLong());
    return uuid.toString();
}

Your problem is that UUID.nameUUIDFromBytes(...) only creates type 3 UUIDs, but you want any UUID type.