Write a program to allow the user to encrypt and decrypt LFSR-based ciphertext using a user-specied key. Speed is very important for stream cipher design,

Write a program to allow the user to encrypt and decrypt LFSR-based ciphertext using a user-specified key. Speed is very important for stream cipher design, so you are required to implement the stream cipher using bitwise operations. There are two files for you to decrypt. I need it done in java. 

(a) LFSR.encrypted was encrypted using the output bits directly from a single 8-bit LFSR with feedback polynomial x8 + x4 + x3 + x2 + 1 and initial fill 255=111111112.

(b) LFSRs.encrypted was encrypted by XORing the output bits from three 8-bit LFSRs with the following feedback polynomials and initial fills. • x8 + x6 + x5 + x + 1, 126=011111102. • x8 + x5 + x3 + x2 + 1, 253=111111012. • x8 + x7 + x6 + x3 + x2 + x + 1, 55=001101112