Decoding Hex: What does this line do (len & 0x01) != 0

Question

I was going through a piece of code in the Apache commons library and was wondering what these conditions do exactly.

public static byte[] decodeHex(final char[         


        

Answer 1

This line checks if len is an odd number or not. If len isn't odd, len & 1 will be equal to 0. (1 and 0x01 are the same value, 0x01 is just the hexadecimal notation)