arduino libraries

Im trying to make an arduino android usb accessory connection, for that i need to use arduino libraries named- 1). usb.h and 2). AndroidAccessory.h

but after importing i get an error like USBHost is not a type, etc.

i dont know what is going wrong, if anyone know a method to run please share.

it may also possible that the file im using are corrupt, if you know where to download it please tell.

P.S- I am using arduino UNO, can we use USBHost in it?