Base64 conversion

Need some help with some conversions.

I have a string of decimal values
85 49 86 18 12 48 195 12 48 195 12 49 194 14 56 195 14 113

which I need to convert to 6 bit ASCII values.

Taking the first 2 values as an example, if I were to do this by hand this is what it would look like.

85 is converted into a hex value of 55
55 is converted into a binary value of 01010101

49 is converted to a hex value of 31
31 is converted into a binary value of 00110001

Put the 2 binary values together to get 0101010100110001
Taking the first 6 digits of the binary, 010101 converts to a hex value of 15
15 in 6 bit Ascii is a U.
Take the next set of 6 digets of the binary, 010011 converts to a hex value of 13
13 in 6 bit Ascii is an S

Ok, so after that painful explaination.
Are there any Java utils that can do this for me?

thanks