src/share/classes/java/math/BigDecimal.java
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@@ -902,16 +902,17 @@
public BigDecimal(double val, MathContext mc) {
if (Double.isInfinite(val) || Double.isNaN(val))
throw new NumberFormatException("Infinite or NaN");
// Translate the double into sign, exponent and significand, according
// to the formulae in JLS, Section 20.10.22.
- int sign = (val >= 0.0 ? 1 : -1); // Preserving sign of zero doesn't matter
- int exponent = Math.getExponent(val);
long valBits = Double.doubleToLongBits(val);
- long significand = (exponent == (Double.MIN_EXPONENT-1)
+ int sign = ((valBits >> 63) == 0 ? 1 : -1);
+ int exponent = (int) ((valBits >> 52) & 0x7ffL);
+ long significand = (exponent == 0
? (valBits & ((1L << 52) - 1)) << 1
: (valBits & ((1L << 52) - 1)) | (1L << 52));
+ exponent -= 1075;
// At this point, val == sign * significand * 2**exponent.
/*
* Special case zero to supress nonterminating normalization and bogus
* scale calculation.
@@ -931,13 +932,11 @@
int scale = 0;
// Calculate intVal and scale
BigInteger intVal;
long compactVal = sign * significand;
if (exponent == 0) {
- // If the exponent is zero, the significant fits in a long
- assert compactVal != INFLATED;
- intVal = null;
+ intVal = (compactVal == INFLATED) ? INFLATED_BIGINT : null;
} else {
if (exponent < 0) {
intVal = BigInteger.valueOf(5).pow(-exponent).multiply(compactVal);
scale = -exponent;
} else { // (exponent > 0)
@@ -4160,19 +4159,34 @@
case ROUND_FLOOR: // Towards -infinity
return qsign < 0;
default: // Some kind of half-way rounding
- if (roundingMode == ROUND_HALF_DOWN ||
- cmpFracHalf < 0 ) // We're closer to higher digit
+ assert roundingMode >= ROUND_HALF_UP &&
+ roundingMode <= ROUND_HALF_EVEN: "Unexpected rounding mode" + RoundingMode.valueOf(roundingMode);
+
+ if (cmpFracHalf < 0 ) // We're closer to higher digit
return false;
- else if (roundingMode == ROUND_HALF_UP ||
- cmpFracHalf > 0 ) // We're closer to lower digit
+ else if (cmpFracHalf > 0 ) // We're closer to lower digit
return true;
- else
- // roundingMode == ROUND_HALF_EVEN, true iff quotient is odd
+ else { // half-way
+ assert cmpFracHalf == 0;
+
+ switch(roundingMode) {
+ case ROUND_HALF_DOWN:
+ return false;
+
+ case ROUND_HALF_UP:
+ return true;
+
+ case ROUND_HALF_EVEN:
return oddQuot;
+
+ default:
+ throw new AssertionError("Unexpected rounding mode" + roundingMode);
+ }
+ }
}
}
/**
* Tests if quotient has to be incremented according the roundingMode