code: public static int positiveRightShift(int key, int shift) {
          int single = 0x3FF >> shift;
          int shiftMask = (single << 22) | (single << 11) | single;
          return shiftMask & (key >> shift);
      }
docs: Shifts the given key to the right.<br> <br> This method only works for keys if all 3 sub-keys are positive
  
  @param key   the key
  @param shift the right shift