JDK 8 code review request for 6964528: Double.toHexString(double d) String manipulation with + in an append of StringBuilder (original) (raw)

Fri Feb 1 21:39:40 UTC 2013

 6964528: Double.toHexString(double d) String manipulation with + in 
       StringBuffer answer = new StringBuffer(24);
       StringBuilder answer = new StringBuilder(24);

        if (Math.copySign(1.0, d) == -1.0)    // value is negative,
            answer.append("-");                  // so append sign
          if(d == 0.0) {
              answer.append("0.0p0");
       }
       else {
       } else {
            boolean subnormal = (d < DoubleConsts.MIN_NORMAL);

            // Isolate significand bits and OR in a high-order bit
           answer.append("p");
            // If the value is subnormal, use the E_min exponent
            // value for double; otherwise, extract and report d's
            // exponent (the representation of a subnormal uses
            // E_min -1).
           answer.append("p" + (subnormal ?
                          DoubleConsts.MIN_EXPONENT:
                          Math.getExponent(d) ));
           answer.append(subnormal ?
                         DoubleConsts.MIN_EXPONENT:
                         Math.getExponent(d));
        }
        return answer.toString();
    }