>>
>>Since the size of the hex presentation is twice the size of the byte array, you have to multiply by 2
>>
>>>> StringBuilder sb = new StringBuilder(length * 2);
>>
>>
>>
>>The bitshift: shifting one bit to the left (provided the argument is not negative) is faster. I prefer that
>>
>>

>>>>           StringBuilder sb = new StringBuilder(length << 1);
>>

>
>Cute :-)

Another thing I have found

(1) You have class with an array member ( I tested static, expect instance also)
(2) A method using that array frequently ( a loop or so)

It is faster to assign the array to a method variable and use the method variable instead of the class member