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src/java.base/share/classes/java/lang/Double.java
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*** 30,39 ****
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import java.lang.constant.ConstantDesc;
import java.util.Optional;
import jdk.internal.math.FloatingDecimal;
import jdk.internal.math.DoubleConsts;
+ import jdk.internal.math.DoubleToDecimal;
import jdk.internal.HotSpotIntrinsicCandidate;
/**
* The {@code Double} class wraps a value of the primitive type
* {@code double} in an object. An object of type
*** 143,215 ****
*/
@SuppressWarnings("unchecked")
public static final Class<Double> TYPE = (Class<Double>) Class.getPrimitiveClass("double");
/**
! * Returns a string representation of the {@code double}
! * argument. All characters mentioned below are ASCII characters.
* <ul>
! * <li>If the argument is NaN, the result is the string
! * "{@code NaN}".
! * <li>Otherwise, the result is a string that represents the sign and
! * magnitude (absolute value) of the argument. If the sign is negative,
! * the first character of the result is '{@code -}'
! * ({@code '\u005Cu002D'}); if the sign is positive, no sign character
! * appears in the result. As for the magnitude <i>m</i>:
* <ul>
! * <li>If <i>m</i> is infinity, it is represented by the characters
! * {@code "Infinity"}; thus, positive infinity produces the result
! * {@code "Infinity"} and negative infinity produces the result
! * {@code "-Infinity"}.
! *
! * <li>If <i>m</i> is zero, it is represented by the characters
! * {@code "0.0"}; thus, negative zero produces the result
! * {@code "-0.0"} and positive zero produces the result
! * {@code "0.0"}.
! *
! * <li>If <i>m</i> is greater than or equal to 10<sup>-3</sup> but less
! * than 10<sup>7</sup>, then it is represented as the integer part of
! * <i>m</i>, in decimal form with no leading zeroes, followed by
! * '{@code .}' ({@code '\u005Cu002E'}), followed by one or
! * more decimal digits representing the fractional part of <i>m</i>.
! *
! * <li>If <i>m</i> is less than 10<sup>-3</sup> or greater than or
! * equal to 10<sup>7</sup>, then it is represented in so-called
! * "computerized scientific notation." Let <i>n</i> be the unique
! * integer such that 10<sup><i>n</i></sup> ≤ <i>m</i> {@literal <}
! * 10<sup><i>n</i>+1</sup>; then let <i>a</i> be the
! * mathematically exact quotient of <i>m</i> and
! * 10<sup><i>n</i></sup> so that 1 ≤ <i>a</i> {@literal <} 10. The
! * magnitude is then represented as the integer part of <i>a</i>,
! * as a single decimal digit, followed by '{@code .}'
! * ({@code '\u005Cu002E'}), followed by decimal digits
! * representing the fractional part of <i>a</i>, followed by the
! * letter '{@code E}' ({@code '\u005Cu0045'}), followed
! * by a representation of <i>n</i> as a decimal integer, as
! * produced by the method {@link Integer#toString(int)}.
* </ul>
* </ul>
- * How many digits must be printed for the fractional part of
- * <i>m</i> or <i>a</i>? There must be at least one digit to represent
- * the fractional part, and beyond that as many, but only as many, more
- * digits as are needed to uniquely distinguish the argument value from
- * adjacent values of type {@code double}. That is, suppose that
- * <i>x</i> is the exact mathematical value represented by the decimal
- * representation produced by this method for a finite nonzero argument
- * <i>d</i>. Then <i>d</i> must be the {@code double} value nearest
- * to <i>x</i>; or if two {@code double} values are equally close
- * to <i>x</i>, then <i>d</i> must be one of them and the least
- * significant bit of the significand of <i>d</i> must be {@code 0}.
*
! * <p>To create localized string representations of a floating-point
! * value, use subclasses of {@link java.text.NumberFormat}.
*
! * @param d the {@code double} to be converted.
! * @return a string representation of the argument.
*/
! public static String toString(double d) {
! return FloatingDecimal.toJavaFormatString(d);
}
/**
* Returns a hexadecimal string representation of the
* {@code double} argument. All characters mentioned below
--- 144,267 ----
*/
@SuppressWarnings("unchecked")
public static final Class<Double> TYPE = (Class<Double>) Class.getPrimitiveClass("double");
/**
! * Returns a string rendering of the {@code double} argument.
! *
! * <p>The characters of the result are all drawn from the ASCII set.
* <ul>
! * <li> Any NaN, whether quiet or signaling, is rendered as
! * {@code "NaN"}, regardless of the sign bit.
! * <li> The infinities +∞ and -∞ are rendered as
! * {@code "Infinity"} and {@code "-Infinity"}, respectively.
! * <li> The positive and negative zeroes are rendered as
! * {@code "0.0"} and {@code "-0.0"}, respectively.
! * <li> A finite negative {@code v} is rendered as the sign
! * '{@code -}' followed by the rendering of the magnitude -{@code v}.
! * <li> A finite positive {@code v} is rendered in two stages:
* <ul>
! * <li> <em>Selection of a decimal</em>: A well-defined
! * decimal <i>d</i><sub><code>v</code></sub> is selected
! * to represent {@code v}.
! * <li> <em>Formatting as a string</em>: The decimal
! * <i>d</i><sub><code>v</code></sub> is formatted as a string,
! * either in plain or in computerized scientific notation,
! * depending on its value.
* </ul>
* </ul>
*
! * <p>A <em>decimal</em> is a number of the form
! * <i>d</i>×10<sup><i>i</i></sup>
! * for some (unique) integers <i>d</i> > 0 and <i>i</i> such that
! * <i>d</i> is not a multiple of 10.
! * These integers are the <em>significand</em> and
! * the <em>exponent</em>, respectively, of the decimal.
! * The <em>length</em> of the decimal is the (unique)
! * integer <i>n</i> meeting
! * 10<sup><i>n</i>-1</sup> ≤ <i>d</i> < 10<sup><i>n</i></sup>.
*
! * <p>The decimal <i>d</i><sub><code>v</code></sub>
! * for a finite positive {@code v} is defined as follows:
! * <ul>
! * <li>Let <i>R</i> be the set of all decimals that round to {@code v}
! * according to the usual round-to-closest rule of
! * IEEE 754 floating-point arithmetic.
! * <li>Let <i>m</i> be the minimal length over all decimals in <i>R</i>.
! * <li>When <i>m</i> ≥ 2, let <i>T</i> be the set of all decimals
! * in <i>R</i> with length <i>m</i>.
! * Otherwise, let <i>T</i> be the set of all decimals
! * in <i>R</i> with length 1 or 2.
! * <li>Define <i>d</i><sub><code>v</code></sub> as
! * the decimal in <i>T</i> that is closest to {@code v}.
! * Or if there are two such decimals in <i>T</i>,
! * select the one with the even significand (there is exactly one).
! * </ul>
! *
! * <p>The (uniquely) selected decimal <i>d</i><sub><code>v</code></sub>
! * is then formatted.
! *
! * <p>Let <i>d</i>, <i>i</i> and <i>n</i> be the significand, exponent and
! * length of <i>d</i><sub><code>v</code></sub>, respectively.
! * Further, let <i>e</i> = <i>n</i> + <i>i</i> - 1 and let
! * <i>d</i><sub>1</sub>…<i>d</i><sub><i>n</i></sub>
! * be the usual decimal expansion of the significand.
! * Note that <i>d</i><sub>1</sub> ≠ 0 ≠ <i>d</i><sub><i>n</i></sub>.
! * <ul>
! * <li>Case -3 ≤ <i>e</i> < 0:
! * <i>d</i><sub><code>v</code></sub> is formatted as
! * <code>0.0</code>…<code>0</code><!--
! * --><i>d</i><sub>1</sub>…<i>d</i><sub><i>n</i></sub>,
! * where there are exactly -(<i>n</i> + <i>i</i>) zeroes between
! * the decimal point and <i>d</i><sub>1</sub>.
! * For example, 123 × 10<sup>-4</sup> is formatted as
! * {@code 0.0123}.
! * <li>Case 0 ≤ <i>e</i> < 7:
! * <ul>
! * <li>Subcase <i>i</i> ≥ 0:
! * <i>d</i><sub><code>v</code></sub> is formatted as
! * <i>d</i><sub>1</sub>…<i>d</i><sub><i>n</i></sub><!--
! * --><code>0</code>…<code>0.0</code>,
! * where there are exactly <i>i</i> zeroes
! * between <i>d</i><sub><i>n</i></sub> and the decimal point.
! * For example, 123 × 10<sup>2</sup> is formatted as
! * {@code 12300.0}.
! * <li>Subcase <i>i</i> < 0:
! * <i>d</i><sub><code>v</code></sub> is formatted as
! * <i>d</i><sub>1</sub>…<!--
! * --><i>d</i><sub><i>n</i>+<i>i</i></sub>.<!--
! * --><i>d</i><sub><i>n</i>+<i>i</i>+1</sub>…<!--
! * --><i>d</i><sub><i>n</i></sub>.
! * There are exactly -<i>i</i> digits to the right of
! * the decimal point.
! * For example, 123 × 10<sup>-1</sup> is formatted as
! * {@code 12.3}.
! * </ul>
! * <li>Case <i>e</i> < -3 or <i>e</i> ≥ 7:
! * computerized scientific notation is used to format
! * <i>d</i><sub><code>v</code></sub>.
! * Here <i>e</i> is formatted as by {@link Integer#toString(int)}.
! * <ul>
! * <li>Subcase <i>n</i> = 1:
! * <i>d</i><sub><code>v</code></sub> is formatted as
! * <i>d</i><sub>1</sub><code>.0E</code><i>e</i>.
! * For example, 1 × 10<sup>23</sup> is formatted as
! * {@code 1.0E23}.
! * <li>Subcase <i>n</i> > 1:
! * <i>d</i><sub><code>v</code></sub> is formatted as
! * <i>d</i><sub>1</sub><code>.</code><i>d</i><sub>2</sub><!--
! * -->…<i>d</i><sub><i>n</i></sub><code>E</code><i>e</i>.
! * For example, 123 × 10<sup>-21</sup> is formatted as
! * {@code 1.23E-19}.
! * </ul>
! * </ul>
! *
! * @param v the {@code double} to be rendered.
! * @return a string rendering of the argument.
*/
! public static String toString(double v) {
! return DoubleToDecimal.toString(v);
}
/**
* Returns a hexadecimal string representation of the
* {@code double} argument. All characters mentioned below
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