code: public BigDecimal negate() {
          if (intCompact == INFLATED) {
              return new BigDecimal(intVal.negate(), INFLATED, scale, precision);
          } else {
              return valueOf(-intCompact, scale, precision);
          }
      }
docs: Returns a {@code BigDecimal} whose value is {@code (-this)},
  and whose scale is {@code this.scale()}.
  
  @return {@code -this}.