How to read UDID, Major, Minor of beacon on android devices?

I am trying to develop a BLE application for Android.

Is the any way through which i can detect and read UDID, Major, Minor of beacon on android devices?

I have read the RadiusNetworks android-ibeacon-service, but I can't understand why:

major = (256 * (0xFF & paramArrayOfByte[(i + 20)]) +
 (0xFF & paramArrayOfByte[(i + 21)]));

which paramArrayOfByte is LeScanCallback byte[] scanRecord