/*
 
* Copyright (c) 1994, 2013, 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
 
* or visit www.oracle.com if you need additional information or have any
 
* questions.
 
*/

package java.lang;

import sun.misc.FloatingDecimal;
import sun.misc.FpUtils;
import sun.misc.DoubleConsts;

/**
 
* 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}.
 
*
 
* @author
  
Lee Boynton
 
* @author
  
Arthur van Hoff
 
* @author
  
Joseph D. Darcy
 
* @since JDK1.0
 
*/

public final class Double extends Number implements Comparable<Double> {
    
/**
     
* 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>)&middot;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 JDK1.1
     
*/

    
@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> &le; <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 &le; <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
 
.
     
*
     
* @param
   
dthe {@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 border>
     
* <caption>Examples</caption>
     
* <tr><th>Floating-point Value</th><th>Hexadecimal String</th>
     
* <tr><td>{@code 1.0}</td> <td>{@code 0x1.0p0}</td>
     
* <tr><td>{@code -1.0}</td>
        
<td>{@code -0x1.0p0}</td>
     
* <tr><td>{@code 2.0}</td> <td>{@code 0x1.0p1}</td>
     
* <tr><td>{@code 3.0}</td> <td>{@code 0x1.8p1}</td>
     
* <tr><td>{@code 0.5}</td> <td>{@code 0x1.0p-1}</td>
     
* <tr><td>{@code 0.25}</td>
        
<td>{@code 0x1.0p-2}</td>
     
* <tr><td>{@code Double.MAX_VALUE}</td>
     
*<td>{@code 0x1.fffffffffffffp1023}</td>
     
* <tr><td>{@code Minimum Normal Value}</td>
     
*<td>{@code 0x1.0p-1022}</td>
     
* <tr><td>{@code Maximum Subnormal Value}</td>
     
*<td>{@code 0x0.fffffffffffffp-1022}</td>
     
* <tr><td>{@code Double.MIN_VALUE}</td>
     
*<td>{@code 0x0.0000000000001p-1022}</td>
     
* </table>
     
* @param
   
dthe {@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 < DoubleConsts.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 ?
                              
DoubleConsts.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&trade; 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
 
/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.
     
* @returna {@code Double} object holding the value
     
*
             
represented by the {@code String} argument.
     
* @throwsNumberFormatException
  
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
     
*/

    
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
   
vthe 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
   
vthe 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) <= DoubleConsts.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
   
valuethe value to be represented by the {@code Double}.
     
*/

    
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
  
sa string to be converted to a {@code Double}.
     
* @throws
    
NumberFormatException
  
if the string does not contain a
     
*
            
parsable number.
     
* @see
       
java.lang.Double#valueOf(java.lang.String)
     
*/

    
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 Conversions
     
* @since JDK1.1
     
*/

    
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 Conversions
     
* @since JDK1.1
     
*/

    
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 Conversions
     
*
     
* @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 Conversions
     
*/

    
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 Conversions
     
* @since JDK1.0
     
*/

    
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
     
*/

    
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.
     
*
     
* <p>Note that in most cases, for two instances of class
     
* {@code Double}, {@code d1} and {@code d2}, the
     
* value of {@code d1.equals(d2)} is {@code true} if and
     
* only if
     
*
     
* <blockquote>
     
*
  
{@code d1.doubleValue() == d2.doubleValue()}
     
* </blockquote>
     
*
     
* <p>also has the value {@code true}. However, there are two
     
* exceptions:
     
* <ul>
     
* <li>If {@code d1} and {@code d2} both represent
     
*{@code Double.NaN}, then the {@code equals} method
     
*returns {@code true}, even though
     
*{@code Double.NaN==Double.NaN} has the value
     
*{@code false}.
     
* <li>If {@code d1} represents {@code +0.0} while
     
*{@code d2} represents {@code -0.0}, or vice versa,
     
*the {@code equal} test has the value {@code false},
     
*even though {@code +0.0==-0.0} has the value {@code true}.
     
* </ul>
     
* This definition allows hash tables to operate properly.
     
* @param
   
objthe object to compare with.
     
* @return
  
{@code true} if the objects are the same;
     
*
          
{@code false} otherwise.
     
* @see java.lang.Double#doubleToLongBits(double)
     
*/

    
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
   
valuea {@code double} precision floating-point number.
     
* @return the bits that represent the floating-point number.
     
*/

    
public static long doubleToLongBits(double value) {
        
long result = doubleToRawLongBits(value);
        
// Check for NaN based on values of bit fields, maximum
        
// exponent and nonzero significand.
        
if ( ((result & DoubleConsts.EXP_BIT_MASK) ==
              
DoubleConsts.EXP_BIT_MASK) &&
             
(result & DoubleConsts.SIGNIF_BIT_MASK) != 0L)
            
result = 0x7ff8000000000000L;
        
return result;
    
}

    
/**
     
* 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
   
valuea {@code double} precision floating-point number.
     
* @return the bits that represent the floating-point number.
     
* @since 1.3
     
*/

    
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>&middot;<i>m</i>&middot;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
   
bitsany {@code long} integer.
     
* @return
  
the {@code double} floating-point value with the same
     
*
          
bit pattern.
     
*/

    
public static native double longBitsToDouble(long bits);

    
/**
     
* Compares two {@code Double} objects numerically.
  
There
     
* are two ways in which comparisons performed by this method
     
* differ from those performed by the Java language numerical
     
* comparison operators ({@code <, <=, ==, >=, >})
     
* when applied to primitive {@code double} values:
     
* <ul><li>
     
*
          
{@code Double.NaN} is considered by this method
     
*
          
to be equal to itself and greater than all other
     
*
          
{@code double} values (including
     
*
          
{@code Double.POSITIVE_INFINITY}).
     
* <li>
     
*
          
{@code 0.0d} is considered by this method to be greater
     
*
          
than {@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>.
     
*
     
* @param
   
anotherDoublethe {@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}.
     
*
     
* @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
     
*
 

     
* @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}
     
*
 

     
* @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}.
     
*
 

     
* @since 1.8
     
*/

    
public static double min(double a, double b) {
        
return Math.min(a, b);
    
}

    
/** use serialVersionUID from JDK 1.0.2 for interoperability */
    
private static final long serialVersionUID = -9172774392245257468L;
}