diff -r 3392f250c784 -r ecbd252fd3a7 emul/mini/src/main/java/java/lang/Double.java --- a/emul/mini/src/main/java/java/lang/Double.java Fri Mar 22 16:59:47 2013 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,994 +0,0 @@ -/* - * Copyright (c) 1994, 2010, 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 org.apidesign.bck2brwsr.core.JavaScriptBody; - -/** - * 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}. - * - *

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 { - /** - * 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}, - * (2-2-52)·21023. 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}, 2-1022. 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}, 2-1074. 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 {@code Class} instance representing the primitive type - * {@code double}. - * - * @since JDK1.1 - */ - public static final Class TYPE = (Class) Class.getPrimitiveClass("double"); - - /** - * Returns a string representation of the {@code double} - * argument. All characters mentioned below are ASCII characters. - *

- * How many digits must be printed for the fractional part of - * m or a? 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 - * x is the exact mathematical value represented by the decimal - * representation produced by this method for a finite nonzero argument - * d. Then d must be the {@code double} value nearest - * to x; or if two {@code double} values are equally close - * to x, then d must be one of them and the least - * significant bit of the significand of d must be {@code 0}. - * - *

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. - */ - @JavaScriptBody(args="d", body="var r = d.toString();" - + "if (r.indexOf('.') === -1) r = r + '.0';" - + "return r;") - public static String toString(double d) { - throw new UnsupportedOperationException(); - } - - /** - * Returns a hexadecimal string representation of the - * {@code double} argument. All characters mentioned below - * are ASCII characters. - * - *

- * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - *

Examples

Floating-point ValueHexadecimal String
{@code 1.0} {@code 0x1.0p0}
{@code -1.0} {@code -0x1.0p0}
{@code 2.0} {@code 0x1.0p1}
{@code 3.0} {@code 0x1.8p1}
{@code 0.5} {@code 0x1.0p-1}
{@code 0.25} {@code 0x1.0p-2}
{@code Double.MAX_VALUE}{@code 0x1.fffffffffffffp1023}
{@code Minimum Normal Value}{@code 0x1.0p-1022}
{@code Maximum Subnormal Value}{@code 0x0.fffffffffffffp-1022}
{@code Double.MIN_VALUE}{@code 0x0.0000000000001p-1022}
- * @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) { - throw new UnsupportedOperationException(); -// /* -// * Modeled after the "a" conversion specifier in C99, section -// * 7.19.6.1; however, the output of this method is more -// * tightly specified. -// */ -// if (!FpUtils.isFinite(d) ) -// // For infinity and NaN, use the decimal output. -// return Double.toString(d); -// else { -// // Initialized to maximum size of output. -// StringBuffer answer = new StringBuffer(24); -// -// if (FpUtils.rawCopySign(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}$", "")); -// -// // If the value is subnormal, use the E_min exponent -// // value for double; otherwise, extract and report d's -// // exponent (the representation of a subnormal uses -// // E_min -1). -// answer.append("p" + (subnormal ? -// DoubleConsts.MIN_EXPONENT: -// FpUtils.getExponent(d) )); -// } -// return answer.toString(); -// } - } - - /** - * Returns a {@code Double} object holding the - * {@code double} value represented by the argument string - * {@code s}. - * - *

If {@code s} is {@code null}, then a - * {@code NullPointerException} is thrown. - * - *

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 FloatValue as described by the lexical - * syntax rules: - * - *

- *
- *
FloatValue: - *
Signopt {@code NaN} - *
Signopt {@code Infinity} - *
Signopt FloatingPointLiteral - *
Signopt HexFloatingPointLiteral - *
SignedInteger - *
- * - *

- * - *

- *
HexFloatingPointLiteral: - *
HexSignificand BinaryExponent FloatTypeSuffixopt - *
- * - *

- * - *

- *
HexSignificand: - *
HexNumeral - *
HexNumeral {@code .} - *
{@code 0x} HexDigitsopt - * {@code .} HexDigits - *
{@code 0X} HexDigitsopt - * {@code .} HexDigits - *
- * - *

- * - *

- *
BinaryExponent: - *
BinaryExponentIndicator SignedInteger - *
- * - *

- * - *

- *
BinaryExponentIndicator: - *
{@code p} - *
{@code P} - *
- * - *
- * - * where Sign, FloatingPointLiteral, - * HexNumeral, HexDigits, SignedInteger and - * FloatTypeSuffix are as defined in the lexical structure - * sections of - * The Java™ Language Specification, - * except that underscores are not accepted between digits. - * If {@code s} does not have the form of - * a FloatValue, 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. - * - *

To interpret localized string representations of a - * floating-point value, use subclasses of {@link - * java.text.NumberFormat}. - * - *

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 - * not 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 not - * 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.) - * - *

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: - * - * - * 

-     *  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
-     *  }
-     *
- * - * - * @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. - */ - @JavaScriptBody(args="s", body="return parseFloat(s);") - public static Double valueOf(String s) throws NumberFormatException { - throw new UnsupportedOperationException(); -// return new Double(FloatingDecimal.readJavaFormatString(s).doubleValue()); - } - - /** - * 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 - */ - @JavaScriptBody(args="s", body="return parseFloat(s);") - public static double parseDouble(String s) throws NumberFormatException { - throw new UnsupportedOperationException(); -// return FloatingDecimal.readJavaFormatString(s).doubleValue(); - } - - /** - * 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. - */ - static public 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. - */ - static public boolean isInfinite(double v) { - return (v == POSITIVE_INFINITY) || (v == NEGATIVE_INFINITY); - } - - /** - * 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}. - */ - 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. - * @see java.lang.Double#valueOf(java.lang.String) - */ - public Double(String s) throws NumberFormatException { - // REMIND: this is inefficient - this(valueOf(s).doubleValue()); - } - - /** - * 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} (by - * casting to a {@code byte}). - * - * @return the {@code double} value represented by this object - * converted to type {@code byte} - * @since JDK1.1 - */ - public byte byteValue() { - return (byte)value; - } - - /** - * Returns the value of this {@code Double} as a - * {@code short} (by casting to a {@code short}). - * - * @return the {@code double} value represented by this object - * converted to type {@code short} - * @since JDK1.1 - */ - public short shortValue() { - return (short)value; - } - - /** - * Returns the value of this {@code Double} as an - * {@code int} (by casting to type {@code int}). - * - * @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} (by casting to type {@code long}). - * - * @return the {@code double} value represented by this object - * converted to type {@code long} - */ - public long longValue() { - return (long)value; - } - - /** - * Returns the {@code float} value of this - * {@code Double} object. - * - * @return the {@code double} value represented by this object - * converted to type {@code float} - * @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 (double)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: - * - *
- * {@code (int)(v^(v>>>32))} - *
- * - * where {@code v} is defined by: - * - *
- * {@code long v = Double.doubleToLongBits(this.doubleValue());} - *
- * - * @return a {@code hash code} value for this object. - */ - public int hashCode() { - 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. - * - *

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 - * - *

- * {@code d1.doubleValue() == d2.doubleValue()} - *
- * - *

also has the value {@code true}. However, there are two - * exceptions: - *

- * This definition allows hash tables to operate properly. - * @param obj the 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) - && (((Double)obj).value) == value; - } - - /** - * Returns a representation of the specified floating-point value - * according to the IEEE 754 floating-point "double - * format" bit layout. - * - *

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. - * - *

If the argument is positive infinity, the result is - * {@code 0x7ff0000000000000L}. - * - *

If the argument is negative infinity, the result is - * {@code 0xfff0000000000000L}. - * - *

If the argument is NaN, the result is - * {@code 0x7ff8000000000000L}. - * - *

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. - */ - public static long doubleToLongBits(double value) { - throw new UnsupportedOperationException(); -// 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. - * - *

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. - * - *

If the argument is positive infinity, the result is - * {@code 0x7ff0000000000000L}. - * - *

If the argument is negative infinity, the result is - * {@code 0xfff0000000000000L}. - * - *

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. - * - *

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 - */ - 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. - * - *

If the argument is {@code 0x7ff0000000000000L}, the result - * is positive infinity. - * - *

If the argument is {@code 0xfff0000000000000L}, the result - * is negative infinity. - * - *

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. - * - *

In all other cases, let s, e, and m be three - * values that can be computed from the argument: - * - * 

-     * int s = ((bits >> 63) == 0) ? 1 : -1;
-     * int e = (int)((bits >> 52) & 0x7ffL);
-     * long m = (e == 0) ?
-     *                 (bits & 0xfffffffffffffL) << 1 :
-     *                 (bits & 0xfffffffffffffL) | 0x10000000000000L;
-     *
- * - * Then the floating-point result equals the value of the mathematical - * expression s·m·2e-1075. - * - *

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 signaling NaNs. 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 - * not 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. - */ - 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: - *

- * This ensures that the natural ordering of - * {@code Double} objects imposed by this method is consistent - * with equals. - * - * @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}. - * - * @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: - * 
-     *    new Double(d1).compareTo(new Double(d2))
-     *
- * - * @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) - } - - /** use serialVersionUID from JDK 1.0.2 for interoperability */ - private static final long serialVersionUID = -9172774392245257468L; -}