question: public static byte [ ] incrementBytes ( byte [ ] value , long amount ) throws IOException { byte [ ] val = value ; if ( val . length < SIZEOF_LONG ) { byte [ ] newvalue ; if ( val [ 0 ] < 0 ) { newvalue = new byte [ ] { - 1 , - 1 , - 1 , - 1 , - 1 , - 1 , - 1 , - 1 } ; } else { newvalue = new byte [ SIZEOF_LONG ] ; } System . arraycopy ( val , 0 , newvalue , newvalue . length - val . length , val . length ) ; val = newvalue ; } else if ( val . length > SIZEOF_LONG ) { throw new IllegalArgumentException ( "Increment Bytes - value too big: " + val . length ) ; } if ( amount == 0 ) return val ; if ( val [ 0 ] < 0 ) { return binaryIncrementNeg ( val , amount ) ; } return binaryIncrementPos ( val , amount ) ; }
target:  Bytewise binary increment/deincrement of long contained in byte array on given amount.