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	/*
	* Copyright (c) 1994, 2021, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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	*/

	package java.lang;

	import java.lang.invoke.MethodHandles;
	import java.lang.constant.Constable;
	import java.lang.constant.ConstantDesc;
	import java.util.Optional;

	import jdk.internal.math.FloatingDecimal;
	import jdk.internal.math.DoubleConsts;
	import jdk.internal.vm.annotation.IntrinsicCandidate;

	/**
	* The {@code Double} class wraps a value of the primitive type
	* {@code double} in an object. An object of type
	* {@code Double} contains a single field whose type is
	* {@code double}.
	*
	* <p>In addition, this class provides several methods for converting a
	* {@code double} to a {@code String} and a
	* {@code String} to a {@code double}, as well as other
	* constants and methods useful when dealing with a
	* {@code double}.
	*
	* <p>This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
	* class; programmers should treat instances that are
	* {@linkplain #equals(Object) equal} as interchangeable and should not
	* use instances for synchronization, or unpredictable behavior may
	* occur. For example, in a future release, synchronization may fail.
	*
	* <h2><a id=equivalenceRelation>Floating-point Equality, Equivalence,
	* and Comparison</a></h2>
	*
	* IEEE 754 floating-point values include finite nonzero values,
	* signed zeros ({@code +0.0} and {@code -0.0}), signed infinities
	* {@linkplain Double#POSITIVE_INFINITY positive infinity} and
	* {@linkplain Double#NEGATIVE_INFINITY negative infinity}), and
	* {@linkplain Double#NaN NaN} (not-a-number).
	*
	* <p>An <em>equivalence relation</em> on a set of values is a boolean
	* relation on pairs of values that is reflexive, symmetric, and
	* transitive. For more discussion of equivalence relations and object
	* equality, see the {@link Object#equals Object.equals}
	* specification. An equivalence relation partitions the values it
	* operates over into sets called <i>equivalence classes</i>. All the
	* members of the equivalence class are equal to each other under the
	* relation. An equivalence class may contain only a single member. At
	* least for some purposes, all the members of an equivalence class
	* are substitutable for each other. In particular, in a numeric
	* expression equivalent values can be <em>substituted</em> for one
	* another without changing the result of the expression, meaning
	* changing the equivalence class of the result of the expression.
	*
	* <p>Notably, the built-in {@code ==} operation on floating-point
	* values is <em>not</em> an equivalence relation. Despite not
	* defining an equivalence relation, the semantics of the IEEE 754
	* {@code ==} operator were deliberately designed to meet other needs
	* of numerical computation. There are two exceptions where the
	* properties of an equivalence relation are not satisfied by {@code
	* ==} on floating-point values:
	*
	* <ul>
	*
	* <li>If {@code v1} and {@code v2} are both NaN, then {@code v1
	* == v2} has the value {@code false}. Therefore, for two NaN
	* arguments the <em>reflexive</em> property of an equivalence
	* relation is <em>not</em> satisfied by the {@code ==} operator.
	*
	* <li>If {@code v1} represents {@code +0.0} while {@code v2}
	* represents {@code -0.0}, or vice versa, then {@code v1 == v2} has
	* the value {@code true} even though {@code +0.0} and {@code -0.0}
	* are distinguishable under various floating-point operations. For
	* example, {@code 1.0/+0.0} evaluates to positive infinity while
	* {@code 1.0/-0.0} evaluates to <em>negative</em> infinity and
	* positive infinity and negative infinity are neither equal to each
	* other nor equivalent to each other. Thus, while a signed zero input
	* most commonly determines the sign of a zero result, because of
	* dividing by zero, {@code +0.0} and {@code -0.0} may not be
	* substituted for each other in general. The sign of a zero input
	* also has a non-substitutable effect on the result of some math
	* library methods.
	*
	* </ul>
	*
	* <p>For ordered comparisons using the built-in comparison operators
	* ({@code <}, {@code <=}, etc.), NaN values have another anomalous
	* situation: a NaN is neither less than, nor greater than, nor equal
	* to any value, including itself. This means the <i>trichotomy of
	* comparison</i> does <em>not</em> hold.
	*
	* <p>To provide the appropriate semantics for {@code equals} and
	* {@code compareTo} methods, those methods cannot simply be wrappers
	* around {@code ==} or ordered comparison operations. Instead, {@link
	* Double#equals equals} defines NaN arguments to be equal to each
	* other and defines {@code +0.0} to <em>not</em> be equal to {@code
	* -0.0}, restoring reflexivity. For comparisons, {@link
	* Double#compareTo compareTo} defines a total order where {@code
	* -0.0} is less than {@code +0.0} and where a NaN is equal to itself
	* and considered greater than positive infinity.
	*
	* <p>The operational semantics of {@code equals} and {@code
	* compareTo} are expressed in terms of {@linkplain #doubleToLongBits
	* bit-wise converting} the floating-point values to integral values.
	*
	* <p>The <em>natural ordering</em> implemented by {@link #compareTo
	* compareTo} is {@linkplain Comparable consistent with equals}. That
	* is, two objects are reported as equal by {@code equals} if and only
	* if {@code compareTo} on those objects returns zero.
	*
	* <p>The adjusted behaviors defined for {@code equals} and {@code
	* compareTo} allow instances of wrapper classes to work properly with
	* conventional data structures. For example, defining NaN
	* values to be {@code equals} to one another allows NaN to be used as
	* an element of a {@link java.util.HashSet HashSet} or as the key of
	* a {@link java.util.HashMap HashMap}. Similarly, defining {@code
	* compareTo} as a total ordering, including {@code +0.0}, {@code
	* -0.0}, and NaN, allows instances of wrapper classes to be used as
	* elements of a {@link java.util.SortedSet SortedSet} or as keys of a
	* {@link java.util.SortedMap SortedMap}.
	*
	* @jls 4.2.3 Floating-Point Types, Formats, and Values
	* @jls 4.2.4. Floating-Point Operations
	* @jls 15.21.1 Numerical Equality Operators == and !=
	* @jls 15.20.1 Numerical Comparison Operators {@code <}, {@code <=}, {@code >}, and {@code >=}
	*
	* @author Lee Boynton
	* @author Arthur van Hoff
	* @author Joseph D. Darcy
	* @since 1.0
	*/
	@jdk.internal.ValueBased
	public final class Double extends Number
	implements Comparable<Double>, Constable, ConstantDesc {
	/**
	* A constant holding the positive infinity of type
	* {@code double}. It is equal to the value returned by
	* {@code Double.longBitsToDouble(0x7ff0000000000000L)}.
	*/
	public static final double POSITIVE_INFINITY = 1.0 / 0.0;

	/**
	* A constant holding the negative infinity of type
	* {@code double}. It is equal to the value returned by
	* {@code Double.longBitsToDouble(0xfff0000000000000L)}.
	*/
	public static final double NEGATIVE_INFINITY = -1.0 / 0.0;

	/**
	* A constant holding a Not-a-Number (NaN) value of type
	* {@code double}. It is equivalent to the value returned by
	* {@code Double.longBitsToDouble(0x7ff8000000000000L)}.
	*/
	public static final double NaN = 0.0d / 0.0;

	/**
	* A constant holding the largest positive finite value of type
	* {@code double},
	* (2-2<sup>-52</sup>)·2<sup>1023</sup>. It is equal to
	* the hexadecimal floating-point literal
	* {@code 0x1.fffffffffffffP+1023} and also equal to
	* {@code Double.longBitsToDouble(0x7fefffffffffffffL)}.
	*/
	public static final double MAX_VALUE = 0x1.fffffffffffffP+1023; // 1.7976931348623157e+308

	/**
	* A constant holding the smallest positive normal value of type
	* {@code double}, 2<sup>-1022</sup>. It is equal to the
	* hexadecimal floating-point literal {@code 0x1.0p-1022} and also
	* equal to {@code Double.longBitsToDouble(0x0010000000000000L)}.
	*
	* @since 1.6
	*/
	public static final double MIN_NORMAL = 0x1.0p-1022; // 2.2250738585072014E-308

	/**
	* A constant holding the smallest positive nonzero value of type
	* {@code double}, 2<sup>-1074</sup>. It is equal to the
	* hexadecimal floating-point literal
	* {@code 0x0.0000000000001P-1022} and also equal to
	* {@code Double.longBitsToDouble(0x1L)}.
	*/
	public static final double MIN_VALUE = 0x0.0000000000001P-1022; // 4.9e-324

	/**
	* Maximum exponent a finite {@code double} variable may have.
	* It is equal to the value returned by
	* {@code Math.getExponent(Double.MAX_VALUE)}.
	*
	* @since 1.6
	*/
	public static final int MAX_EXPONENT = 1023;

	/**
	* Minimum exponent a normalized {@code double} variable may
	* have. It is equal to the value returned by
	* {@code Math.getExponent(Double.MIN_NORMAL)}.
	*
	* @since 1.6
	*/
	public static final int MIN_EXPONENT = -1022;

	/**
	* The number of bits used to represent a {@code double} value.
	*
	* @since 1.5
	*/
	public static final int SIZE = 64;

	/**
	* The number of bytes used to represent a {@code double} value.
	*
	* @since 1.8
	*/
	public static final int BYTES = SIZE / Byte.SIZE;

	/**
	* The {@code Class} instance representing the primitive type
	* {@code double}.
	*
	* @since 1.1
	*/
	@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
	* 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 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 string
	* {@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 string
	* {@code "0x0.0p0"}; thus, negative zero produces the result
	* {@code "-0x0.0p0"} and positive zero produces the result
	* {@code "0x0.0p0"}.
	*
	* <li>If <i>m</i> is a {@code double} value with a
	* normalized representation, substrings are used to represent the
	* significand and exponent fields. The significand is
	* represented by the characters {@code "0x1."}
	* followed by a lowercase hexadecimal representation of the rest
	* of the significand as a fraction. Trailing zeros in the
	* hexadecimal representation are removed unless all the digits
	* are zero, in which case a single zero is used. Next, the
	* exponent is represented by {@code "p"} followed
	* by a decimal string of the unbiased exponent as if produced by
	* a call to {@link Integer#toString(int) Integer.toString} on the
	* exponent value.
	*
	* <li>If <i>m</i> is a {@code double} value with a subnormal
	* representation, the significand is represented by the
	* characters {@code "0x0."} followed by a
	* hexadecimal representation of the rest of the significand as a
	* fraction. Trailing zeros in the hexadecimal representation are
	* removed. Next, the exponent is represented by
	* {@code "p-1022"}. Note that there must be at
	* least one nonzero digit in a subnormal significand.
	*
	* </ul>
	*
	* </ul>
	*
	* <table class="striped">
	* <caption>Examples</caption>
	* <thead>
	* <tr><th scope="col">Floating-point Value</th><th scope="col">Hexadecimal String</th>
	* </thead>
	* <tbody style="text-align:right">
	* <tr><th scope="row">{@code 1.0}</th> <td>{@code 0x1.0p0}</td>
	* <tr><th scope="row">{@code -1.0}</th> <td>{@code -0x1.0p0}</td>
	* <tr><th scope="row">{@code 2.0}</th> <td>{@code 0x1.0p1}</td>
	* <tr><th scope="row">{@code 3.0}</th> <td>{@code 0x1.8p1}</td>
	* <tr><th scope="row">{@code 0.5}</th> <td>{@code 0x1.0p-1}</td>
	* <tr><th scope="row">{@code 0.25}</th> <td>{@code 0x1.0p-2}</td>
	* <tr><th scope="row">{@code Double.MAX_VALUE}</th>
	* <td>{@code 0x1.fffffffffffffp1023}</td>
	* <tr><th scope="row">{@code Minimum Normal Value}</th>
	* <td>{@code 0x1.0p-1022}</td>
	* <tr><th scope="row">{@code Maximum Subnormal Value}</th>
	* <td>{@code 0x0.fffffffffffffp-1022}</td>
	* <tr><th scope="row">{@code Double.MIN_VALUE}</th>
	* <td>{@code 0x0.0000000000001p-1022}</td>
	* </tbody>
	* </table>
	* @param d the {@code double} to be converted.
	* @return a hex string representation of the argument.
	* @since 1.5
	* @author Joseph D. Darcy
	*/
	public static String toHexString(double d) {
	/*
	* Modeled after the "a" conversion specifier in C99, section
	* 7.19.6.1; however, the output of this method is more
	* tightly specified.
	*/
	if (!isFinite(d) )
	// For infinity and NaN, use the decimal output.
	return Double.toString(d);
	else {
	// Initialized to maximum size of output.
	StringBuilder answer = new StringBuilder(24);

	if (Math.copySign(1.0, d) == -1.0) // value is negative,
	answer.append("-"); // so append sign info

	answer.append("0x");

	d = Math.abs(d);

	if(d == 0.0) {
	answer.append("0.0p0");
	} else {
	boolean subnormal = (d < Double.MIN_NORMAL);

	// Isolate significand bits and OR in a high-order bit
	// so that the string representation has a known
	// length.
	long signifBits = (Double.doubleToLongBits(d)
	& DoubleConsts.SIGNIF_BIT_MASK) \|
	0x1000000000000000L;

	// Subnormal values have a 0 implicit bit; normal
	// values have a 1 implicit bit.
	answer.append(subnormal ? "0." : "1.");

	// Isolate the low-order 13 digits of the hex
	// representation. If all the digits are zero,
	// replace with a single 0; otherwise, remove all
	// trailing zeros.
	String signif = Long.toHexString(signifBits).substring(3,16);
	answer.append(signif.equals("0000000000000") ? // 13 zeros
	"0":
	signif.replaceFirst("0{1,12}$", ""));

	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(subnormal ?
	Double.MIN_EXPONENT:
	Math.getExponent(d));
	}
	return answer.toString();
	}
	}

	/**
	* Returns a {@code Double} object holding the
	* {@code double} value represented by the argument string
	* {@code s}.
	*
	* <p>If {@code s} is {@code null}, then a
	* {@code NullPointerException} is thrown.
	*
	* <p>Leading and trailing whitespace characters in {@code s}
	* are ignored. Whitespace is removed as if by the {@link
	* String#trim} method; that is, both ASCII space and control
	* characters are removed. The rest of {@code s} should
	* constitute a <i>FloatValue</i> as described by the lexical
	* syntax rules:
	*
	* <blockquote>
	* <dl>
	* <dt><i>FloatValue:</i>
	* <dd><i>Sign<sub>opt</sub></i> {@code NaN}
	* <dd><i>Sign<sub>opt</sub></i> {@code Infinity}
	* <dd><i>Sign<sub>opt</sub> FloatingPointLiteral</i>
	* <dd><i>Sign<sub>opt</sub> HexFloatingPointLiteral</i>
	* <dd><i>SignedInteger</i>
	* </dl>
	*
	* <dl>
	* <dt><i>HexFloatingPointLiteral</i>:
	* <dd> <i>HexSignificand BinaryExponent FloatTypeSuffix<sub>opt</sub></i>
	* </dl>
	*
	* <dl>
	* <dt><i>HexSignificand:</i>
	* <dd><i>HexNumeral</i>
	* <dd><i>HexNumeral</i> {@code .}
	* <dd>{@code 0x} <i>HexDigits<sub>opt</sub>
	* </i>{@code .}<i> HexDigits</i>
	* <dd>{@code 0X}<i> HexDigits<sub>opt</sub>
	* </i>{@code .} <i>HexDigits</i>
	* </dl>
	*
	* <dl>
	* <dt><i>BinaryExponent:</i>
	* <dd><i>BinaryExponentIndicator SignedInteger</i>
	* </dl>
	*
	* <dl>
	* <dt><i>BinaryExponentIndicator:</i>
	* <dd>{@code p}
	* <dd>{@code P}
	* </dl>
	*
	* </blockquote>
	*
	* where <i>Sign</i>, <i>FloatingPointLiteral</i>,
	* <i>HexNumeral</i>, <i>HexDigits</i>, <i>SignedInteger</i> and
	* <i>FloatTypeSuffix</i> are as defined in the lexical structure
	* sections of
	* <cite>The Java Language Specification</cite>,
	* except that underscores are not accepted between digits.
	* If {@code s} does not have the form of
	* a <i>FloatValue</i>, then a {@code NumberFormatException}
	* is thrown. Otherwise, {@code s} is regarded as
	* representing an exact decimal value in the usual
	* "computerized scientific notation" or as an exact
	* hexadecimal value; this exact numerical value is then
	* conceptually converted to an "infinitely precise"
	* binary value that is then rounded to type {@code double}
	* by the usual round-to-nearest rule of IEEE 754 floating-point
	* arithmetic, which includes preserving the sign of a zero
	* value.
	*
	* Note that the round-to-nearest rule also implies overflow and
	* underflow behaviour; if the exact value of {@code s} is large
	* enough in magnitude (greater than or equal to ({@link
	* #MAX_VALUE} + {@link Math#ulp(double) ulp(MAX_VALUE)}/2),
	* rounding to {@code double} will result in an infinity and if the
	* exact value of {@code s} is small enough in magnitude (less
	* than or equal to {@link #MIN_VALUE}/2), rounding to float will
	* result in a zero.
	*
	* Finally, after rounding a {@code Double} object representing
	* this {@code double} value is returned.
	*
	* <p> To interpret localized string representations of a
	* floating-point value, use subclasses of {@link
	* java.text.NumberFormat}.
	*
	* <p>Note that trailing format specifiers, specifiers that
	* determine the type of a floating-point literal
	* ({@code 1.0f} is a {@code float} value;
	* {@code 1.0d} is a {@code double} value), do
	* <em>not</em> influence the results of this method. In other
	* words, the numerical value of the input string is converted
	* directly to the target floating-point type. The two-step
	* sequence of conversions, string to {@code float} followed
	* by {@code float} to {@code double}, is <em>not</em>
	* equivalent to converting a string directly to
	* {@code double}. For example, the {@code float}
	* literal {@code 0.1f} is equal to the {@code double}
	* value {@code 0.10000000149011612}; the {@code float}
	* literal {@code 0.1f} represents a different numerical
	* value than the {@code double} literal
	* {@code 0.1}. (The numerical value 0.1 cannot be exactly
	* represented in a binary floating-point number.)
	*
	* <p>To avoid calling this method on an invalid string and having
	* a {@code NumberFormatException} be thrown, the regular
	* expression below can be used to screen the input string:
	*
	* <pre>{@code
	* final String Digits = "(\\p{Digit}+)";
	* final String HexDigits = "(\\p{XDigit}+)";
	* // an exponent is 'e' or 'E' followed by an optionally
	* // signed decimal integer.
	* final String Exp = "[eE][+-]?"+Digits;
	* final String fpRegex =
	* ("[\\x00-\\x20]*"+ // Optional leading "whitespace"
	* "[+-]?(" + // Optional sign character
	* "NaN\|" + // "NaN" string
	* "Infinity\|" + // "Infinity" string
	*
	* // A decimal floating-point string representing a finite positive
	* // number without a leading sign has at most five basic pieces:
	* // Digits . Digits ExponentPart FloatTypeSuffix
	* //
	* // Since this method allows integer-only strings as input
	* // in addition to strings of floating-point literals, the
	* // two sub-patterns below are simplifications of the grammar
	* // productions from section 3.10.2 of
	* // The Java Language Specification.
	*
	* // Digits ._opt Digits_opt ExponentPart_opt FloatTypeSuffix_opt
	* "((("+Digits+"(\\.)?("+Digits+"?)("+Exp+")?)\|"+
	*
	* // . Digits ExponentPart_opt FloatTypeSuffix_opt
	* "(\\.("+Digits+")("+Exp+")?)\|"+
	*
	* // Hexadecimal strings
	* "((" +
	* // 0[xX] HexDigits ._opt BinaryExponent FloatTypeSuffix_opt
	* "(0[xX]" + HexDigits + "(\\.)?)\|" +
	*
	* // 0[xX] HexDigits_opt . HexDigits BinaryExponent FloatTypeSuffix_opt
	* "(0[xX]" + HexDigits + "?(\\.)" + HexDigits + ")" +
	*
	* ")[pP][+-]?" + Digits + "))" +
	* "[fFdD]?))" +
	* "[\\x00-\\x20]*");// Optional trailing "whitespace"
	*
	* if (Pattern.matches(fpRegex, myString))
	* Double.valueOf(myString); // Will not throw NumberFormatException
	* else {
	* // Perform suitable alternative action
	* }
	* }</pre>
	*
	* @param s the string to be parsed.
	* @return a {@code Double} object holding the value
	* represented by the {@code String} argument.
	* @throws NumberFormatException if the string does not contain a
	* parsable number.
	*/
	public static Double valueOf(String s) throws NumberFormatException {
	return new Double(parseDouble(s));
	}

	/**
	* Returns a {@code Double} instance representing the specified
	* {@code double} value.
	* If a new {@code Double} instance is not required, this method
	* should generally be used in preference to the constructor
	* {@link #Double(double)}, as this method is likely to yield
	* significantly better space and time performance by caching
	* frequently requested values.
	*
	* @param d a double value.
	* @return a {@code Double} instance representing {@code d}.
	* @since 1.5
	*/
	@IntrinsicCandidate
	public static Double valueOf(double d) {
	return new Double(d);
	}

	/**
	* Returns a new {@code double} initialized to the value
	* represented by the specified {@code String}, as performed
	* by the {@code valueOf} method of class
	* {@code Double}.
	*
	* @param s the string to be parsed.
	* @return the {@code double} value represented by the string
	* argument.
	* @throws NullPointerException if the string is null
	* @throws NumberFormatException if the string does not contain
	* a parsable {@code double}.
	* @see java.lang.Double#valueOf(String)
	* @since 1.2
	*/
	public static double parseDouble(String s) throws NumberFormatException {
	return FloatingDecimal.parseDouble(s);
	}

	/**
	* Returns {@code true} if the specified number is a
	* Not-a-Number (NaN) value, {@code false} otherwise.
	*
	* @param v the value to be tested.
	* @return {@code true} if the value of the argument is NaN;
	* {@code false} otherwise.
	*/
	public static boolean isNaN(double v) {
	return (v != v);
	}

	/**
	* Returns {@code true} if the specified number is infinitely
	* large in magnitude, {@code false} otherwise.
	*
	* @param v the value to be tested.
	* @return {@code true} if the value of the argument is positive
	* infinity or negative infinity; {@code false} otherwise.
	*/
	public static boolean isInfinite(double v) {
	return (v == POSITIVE_INFINITY) \|\| (v == NEGATIVE_INFINITY);
	}

	/**
	* Returns {@code true} if the argument is a finite floating-point
	* value; returns {@code false} otherwise (for NaN and infinity
	* arguments).
	*
	* @param d the {@code double} value to be tested
	* @return {@code true} if the argument is a finite
	* floating-point value, {@code false} otherwise.
	* @since 1.8
	*/
	public static boolean isFinite(double d) {
	return Math.abs(d) <= Double.MAX_VALUE;
	}

	/**
	* The value of the Double.
	*
	* @serial
	*/
	private final double value;

	/**
	* Constructs a newly allocated {@code Double} object that
	* represents the primitive {@code double} argument.
	*
	* @param value the value to be represented by the {@code Double}.
	*
	* @deprecated
	* It is rarely appropriate to use this constructor. The static factory
	* {@link #valueOf(double)} is generally a better choice, as it is
	* likely to yield significantly better space and time performance.
	*/
	@Deprecated(since="9", forRemoval = true)
	public Double(double value) {
	this.value = value;
	}

	/**
	* Constructs a newly allocated {@code Double} object that
	* represents the floating-point value of type {@code double}
	* represented by the string. The string is converted to a
	* {@code double} value as if by the {@code valueOf} method.
	*
	* @param s a string to be converted to a {@code Double}.
	* @throws NumberFormatException if the string does not contain a
	* parsable number.
	*
	* @deprecated
	* It is rarely appropriate to use this constructor.
	* Use {@link #parseDouble(String)} to convert a string to a
	* {@code double} primitive, or use {@link #valueOf(String)}
	* to convert a string to a {@code Double} object.
	*/
	@Deprecated(since="9", forRemoval = true)
	public Double(String s) throws NumberFormatException {
	value = parseDouble(s);
	}

	/**
	* Returns {@code true} if this {@code Double} value is
	* a Not-a-Number (NaN), {@code false} otherwise.
	*
	* @return {@code true} if the value represented by this object is
	* NaN; {@code false} otherwise.
	*/
	public boolean isNaN() {
	return isNaN(value);
	}

	/**
	* Returns {@code true} if this {@code Double} value is
	* infinitely large in magnitude, {@code false} otherwise.
	*
	* @return {@code true} if the value represented by this object is
	* positive infinity or negative infinity;
	* {@code false} otherwise.
	*/
	public boolean isInfinite() {
	return isInfinite(value);
	}

	/**
	* Returns a string representation of this {@code Double} object.
	* The primitive {@code double} value represented by this
	* object is converted to a string exactly as if by the method
	* {@code toString} of one argument.
	*
	* @return a {@code String} representation of this object.
	* @see java.lang.Double#toString(double)
	*/
	public String toString() {
	return toString(value);
	}

	/**
	* Returns the value of this {@code Double} as a {@code byte}
	* after a narrowing primitive conversion.
	*
	* @return the {@code double} value represented by this object
	* converted to type {@code byte}
	* @jls 5.1.3 Narrowing Primitive Conversion
	* @since 1.1
	*/
	public byte byteValue() {
	return (byte)value;
	}

	/**
	* Returns the value of this {@code Double} as a {@code short}
	* after a narrowing primitive conversion.
	*
	* @return the {@code double} value represented by this object
	* converted to type {@code short}
	* @jls 5.1.3 Narrowing Primitive Conversion
	* @since 1.1
	*/
	public short shortValue() {
	return (short)value;
	}

	/**
	* Returns the value of this {@code Double} as an {@code int}
	* after a narrowing primitive conversion.
	* @jls 5.1.3 Narrowing Primitive Conversion
	*
	* @return the {@code double} value represented by this object
	* converted to type {@code int}
	*/
	public int intValue() {
	return (int)value;
	}

	/**
	* Returns the value of this {@code Double} as a {@code long}
	* after a narrowing primitive conversion.
	*
	* @return the {@code double} value represented by this object
	* converted to type {@code long}
	* @jls 5.1.3 Narrowing Primitive Conversion
	*/
	public long longValue() {
	return (long)value;
	}

	/**
	* Returns the value of this {@code Double} as a {@code float}
	* after a narrowing primitive conversion.
	*
	* @return the {@code double} value represented by this object
	* converted to type {@code float}
	* @jls 5.1.3 Narrowing Primitive Conversion
	* @since 1.0
	*/
	public float floatValue() {
	return (float)value;
	}

	/**
	* Returns the {@code double} value of this {@code Double} object.
	*
	* @return the {@code double} value represented by this object
	*/
	@IntrinsicCandidate
	public double doubleValue() {
	return value;
	}

	/**
	* Returns a hash code for this {@code Double} object. The
	* result is the exclusive OR of the two halves of the
	* {@code long} integer bit representation, exactly as
	* produced by the method {@link #doubleToLongBits(double)}, of
	* the primitive {@code double} value represented by this
	* {@code Double} object. That is, the hash code is the value
	* of the expression:
	*
	* <blockquote>
	* {@code (int)(v^(v>>>32))}
	* </blockquote>
	*
	* where {@code v} is defined by:
	*
	* <blockquote>
	* {@code long v = Double.doubleToLongBits(this.doubleValue());}
	* </blockquote>
	*
	* @return a {@code hash code} value for this object.
	*/
	@Override
	public int hashCode() {
	return Double.hashCode(value);
	}

	/**
	* Returns a hash code for a {@code double} value; compatible with
	* {@code Double.hashCode()}.
	*
	* @param value the value to hash
	* @return a hash code value for a {@code double} value.
	* @since 1.8
	*/
	public static int hashCode(double value) {
	long bits = doubleToLongBits(value);
	return (int)(bits ^ (bits >>> 32));
	}

	/**
	* Compares this object against the specified object. The result
	* is {@code true} if and only if the argument is not
	* {@code null} and is a {@code Double} object that
	* represents a {@code double} that has the same value as the
	* {@code double} represented by this object. For this
	* purpose, two {@code double} values are considered to be
	* the same if and only if the method {@link
	* #doubleToLongBits(double)} returns the identical
	* {@code long} value when applied to each.
	*
	* @apiNote
	* This method is defined in terms of {@link
	* #doubleToLongBits(double)} rather than the {@code ==} operator
	* on {@code double} values since the {@code ==} operator does
	* <em>not</em> define an equivalence relation and to satisfy the
	* {@linkplain Object#equals equals contract} an equivalence
	* relation must be implemented; see <a
	* href="#equivalenceRelation">this discussion</a> for details of
	* floating-point equality and equivalence.
	*
	* @see java.lang.Double#doubleToLongBits(double)
	* @jls 15.21.1 Numerical Equality Operators == and !=
	*/
	public boolean equals(Object obj) {
	return (obj instanceof Double)
	&& (doubleToLongBits(((Double)obj).value) ==
	doubleToLongBits(value));
	}

	/**
	* Returns a representation of the specified floating-point value
	* according to the IEEE 754 floating-point "double
	* format" bit layout.
	*
	* <p>Bit 63 (the bit that is selected by the mask
	* {@code 0x8000000000000000L}) represents the sign of the
	* floating-point number. Bits
	* 62-52 (the bits that are selected by the mask
	* {@code 0x7ff0000000000000L}) represent the exponent. Bits 51-0
	* (the bits that are selected by the mask
	* {@code 0x000fffffffffffffL}) represent the significand
	* (sometimes called the mantissa) of the floating-point number.
	*
	* <p>If the argument is positive infinity, the result is
	* {@code 0x7ff0000000000000L}.
	*
	* <p>If the argument is negative infinity, the result is
	* {@code 0xfff0000000000000L}.
	*
	* <p>If the argument is NaN, the result is
	* {@code 0x7ff8000000000000L}.
	*
	* <p>In all cases, the result is a {@code long} integer that, when
	* given to the {@link #longBitsToDouble(long)} method, will produce a
	* floating-point value the same as the argument to
	* {@code doubleToLongBits} (except all NaN values are
	* collapsed to a single "canonical" NaN value).
	*
	* @param value a {@code double} precision floating-point number.
	* @return the bits that represent the floating-point number.
	*/
	@IntrinsicCandidate
	public static long doubleToLongBits(double value) {
	if (!isNaN(value)) {
	return doubleToRawLongBits(value);
	}
	return 0x7ff8000000000000L;
	}

	/**
	* Returns a representation of the specified floating-point value
	* according to the IEEE 754 floating-point "double
	* format" bit layout, preserving Not-a-Number (NaN) values.
	*
	* <p>Bit 63 (the bit that is selected by the mask
	* {@code 0x8000000000000000L}) represents the sign of the
	* floating-point number. Bits
	* 62-52 (the bits that are selected by the mask
	* {@code 0x7ff0000000000000L}) represent the exponent. Bits 51-0
	* (the bits that are selected by the mask
	* {@code 0x000fffffffffffffL}) represent the significand
	* (sometimes called the mantissa) of the floating-point number.
	*
	* <p>If the argument is positive infinity, the result is
	* {@code 0x7ff0000000000000L}.
	*
	* <p>If the argument is negative infinity, the result is
	* {@code 0xfff0000000000000L}.
	*
	* <p>If the argument is NaN, the result is the {@code long}
	* integer representing the actual NaN value. Unlike the
	* {@code doubleToLongBits} method,
	* {@code doubleToRawLongBits} does not collapse all the bit
	* patterns encoding a NaN to a single "canonical" NaN
	* value.
	*
	* <p>In all cases, the result is a {@code long} integer that,
	* when given to the {@link #longBitsToDouble(long)} method, will
	* produce a floating-point value the same as the argument to
	* {@code doubleToRawLongBits}.
	*
	* @param value a {@code double} precision floating-point number.
	* @return the bits that represent the floating-point number.
	* @since 1.3
	*/
	@IntrinsicCandidate
	public static native long doubleToRawLongBits(double value);

	/**
	* Returns the {@code double} value corresponding to a given
	* bit representation.
	* The argument is considered to be a representation of a
	* floating-point value according to the IEEE 754 floating-point
	* "double format" bit layout.
	*
	* <p>If the argument is {@code 0x7ff0000000000000L}, the result
	* is positive infinity.
	*
	* <p>If the argument is {@code 0xfff0000000000000L}, the result
	* is negative infinity.
	*
	* <p>If the argument is any value in the range
	* {@code 0x7ff0000000000001L} through
	* {@code 0x7fffffffffffffffL} or in the range
	* {@code 0xfff0000000000001L} through
	* {@code 0xffffffffffffffffL}, the result is a NaN. No IEEE
	* 754 floating-point operation provided by Java can distinguish
	* between two NaN values of the same type with different bit
	* patterns. Distinct values of NaN are only distinguishable by
	* use of the {@code Double.doubleToRawLongBits} method.
	*
	* <p>In all other cases, let <i>s</i>, <i>e</i>, and <i>m</i> be three
	* values that can be computed from the argument:
	*
	* <blockquote><pre>{@code
	* int s = ((bits >> 63) == 0) ? 1 : -1;
	* int e = (int)((bits >> 52) & 0x7ffL);
	* long m = (e == 0) ?
	* (bits & 0xfffffffffffffL) << 1 :
	* (bits & 0xfffffffffffffL) \| 0x10000000000000L;
	* }</pre></blockquote>
	*
	* Then the floating-point result equals the value of the mathematical
	* expression <i>s</i>·<i>m</i>·2<sup><i>e</i>-1075</sup>.
	*
	* <p>Note that this method may not be able to return a
	* {@code double} NaN with exactly same bit pattern as the
	* {@code long} argument. IEEE 754 distinguishes between two
	* kinds of NaNs, quiet NaNs and <i>signaling NaNs</i>. The
	* differences between the two kinds of NaN are generally not
	* visible in Java. Arithmetic operations on signaling NaNs turn
	* them into quiet NaNs with a different, but often similar, bit
	* pattern. However, on some processors merely copying a
	* signaling NaN also performs that conversion. In particular,
	* copying a signaling NaN to return it to the calling method
	* may perform this conversion. So {@code longBitsToDouble}
	* may not be able to return a {@code double} with a
	* signaling NaN bit pattern. Consequently, for some
	* {@code long} values,
	* {@code doubleToRawLongBits(longBitsToDouble(start))} may
	* <i>not</i> equal {@code start}. Moreover, which
	* particular bit patterns represent signaling NaNs is platform
	* dependent; although all NaN bit patterns, quiet or signaling,
	* must be in the NaN range identified above.
	*
	* @param bits any {@code long} integer.
	* @return the {@code double} floating-point value with the same
	* bit pattern.
	*/
	@IntrinsicCandidate
	public static native double longBitsToDouble(long bits);

	/**
	* Compares two {@code Double} objects numerically.
	*
	* This method imposes a total order on {@code Double} objects
	* with two differences compared to the incomplete order defined by
	* the Java language numerical comparison operators ({@code <, <=,
	* ==, >=, >}) on {@code double} values.
	*
	* <ul><li> A NaN is <em>unordered</em> with respect to other
	* values and unequal to itself under the comparison
	* operators. This method chooses to define {@code
	* Double.NaN} to be equal to itself and greater than all
	* other {@code double} values (including {@code
	* Double.POSITIVE_INFINITY}).
	*
	* <li> Positive zero and negative zero compare equal
	* numerically, but are distinct and distinguishable values.
	* This method chooses to define positive zero ({@code +0.0d}),
	* to be greater than negative zero ({@code -0.0d}).
	* </ul>

	* This ensures that the <i>natural ordering</i> of {@code Double}
	* objects imposed by this method is <i>consistent with
	* equals</i>; see <a href="#equivalenceRelation">this
	* discussion</a> for details of floating-point comparison and
	* ordering.
	*
	* @param anotherDouble the {@code Double} to be compared.
	* @return the value {@code 0} if {@code anotherDouble} is
	* numerically equal to this {@code Double}; a value
	* less than {@code 0} if this {@code Double}
	* is numerically less than {@code anotherDouble};
	* and a value greater than {@code 0} if this
	* {@code Double} is numerically greater than
	* {@code anotherDouble}.
	*
	* @jls 15.20.1 Numerical Comparison Operators {@code <}, {@code <=}, {@code >}, and {@code >=}
	* @since 1.2
	*/
	public int compareTo(Double anotherDouble) {
	return Double.compare(value, anotherDouble.value);
	}

	/**
	* Compares the two specified {@code double} values. The sign
	* of the integer value returned is the same as that of the
	* integer that would be returned by the call:
	* <pre>
	* new Double(d1).compareTo(new Double(d2))
	* </pre>
	*
	* @param d1 the first {@code double} to compare
	* @param d2 the second {@code double} to compare
	* @return the value {@code 0} if {@code d1} is
	* numerically equal to {@code d2}; a value less than
	* {@code 0} if {@code d1} is numerically less than
	* {@code d2}; and a value greater than {@code 0}
	* if {@code d1} is numerically greater than
	* {@code d2}.
	* @since 1.4
	*/
	public static int compare(double d1, double d2) {
	if (d1 < d2)
	return -1; // Neither val is NaN, thisVal is smaller
	if (d1 > d2)
	return 1; // Neither val is NaN, thisVal is larger

	// Cannot use doubleToRawLongBits because of possibility of NaNs.
	long thisBits = Double.doubleToLongBits(d1);
	long anotherBits = Double.doubleToLongBits(d2);

	return (thisBits == anotherBits ? 0 : // Values are equal
	(thisBits < anotherBits ? -1 : // (-0.0, 0.0) or (!NaN, NaN)
	1)); // (0.0, -0.0) or (NaN, !NaN)
	}

	/**
	* Adds two {@code double} values together as per the + operator.
	*
	* @param a the first operand
	* @param b the second operand
	* @return the sum of {@code a} and {@code b}
	* @jls 4.2.4 Floating-Point Operations
	* @see java.util.function.BinaryOperator
	* @since 1.8
	*/
	public static double sum(double a, double b) {
	return a + b;
	}

	/**
	* Returns the greater of two {@code double} values
	* as if by calling {@link Math#max(double, double) Math.max}.
	*
	* @param a the first operand
	* @param b the second operand
	* @return the greater of {@code a} and {@code b}
	* @see java.util.function.BinaryOperator
	* @since 1.8
	*/
	public static double max(double a, double b) {
	return Math.max(a, b);
	}

	/**
	* Returns the smaller of two {@code double} values
	* as if by calling {@link Math#min(double, double) Math.min}.
	*
	* @param a the first operand
	* @param b the second operand
	* @return the smaller of {@code a} and {@code b}.
	* @see java.util.function.BinaryOperator
	* @since 1.8
	*/
	public static double min(double a, double b) {
	return Math.min(a, b);
	}

	/**
	* Returns an {@link Optional} containing the nominal descriptor for this
	* instance, which is the instance itself.
	*
	* @return an {@link Optional} describing the {@linkplain Double} instance
	* @since 12
	*/
	@Override
	public Optional<Double> describeConstable() {
	return Optional.of(this);
	}

	/**
	* Resolves this instance as a {@link ConstantDesc}, the result of which is
	* the instance itself.
	*
	* @param lookup ignored
	* @return the {@linkplain Double} instance
	* @since 12
	*/
	@Override
	public Double resolveConstantDesc(MethodHandles.Lookup lookup) {
	return this;
	}

	/** use serialVersionUID from JDK 1.0.2 for interoperability */
	@java.io.Serial
	private static final long serialVersionUID = -9172774392245257468L;
	}

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