Casting

[apollo house]

I have a Stream of bytes from a file, I wish to cast the byte array into various data types eg int doubles etc( no I cannot do this at the file read stage due to the nature and format of the data), but under compilation I either get on the data from the first byte or complier warnings being 'unable to cast byte[] to int'. How can I convert an array of bytes to another data type eg a 2 byte array to an int. Thnaks in advance