In order to support fields of the same name in subclasses we are now prefixing them with name of the class that defines them. To provide convenient way to access them from generated bytecode and also directly from JavaScript, there is a getter/setter function for each field. It starts with _ followed by the field name. If called with a parameter, it sets the field, with a parameter it just returns it.
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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28 import org.apidesign.bck2brwsr.core.JavaScriptBody;
31 * The {@code Double} class wraps a value of the primitive type
32 * {@code double} in an object. An object of type
33 * {@code Double} contains a single field whose type is
36 * <p>In addition, this class provides several methods for converting a
37 * {@code double} to a {@code String} and a
38 * {@code String} to a {@code double}, as well as other
39 * constants and methods useful when dealing with a
43 * @author Arthur van Hoff
44 * @author Joseph D. Darcy
47 public final class Double extends Number implements Comparable<Double> {
49 * A constant holding the positive infinity of type
50 * {@code double}. It is equal to the value returned by
51 * {@code Double.longBitsToDouble(0x7ff0000000000000L)}.
53 public static final double POSITIVE_INFINITY = 1.0 / 0.0;
56 * A constant holding the negative infinity of type
57 * {@code double}. It is equal to the value returned by
58 * {@code Double.longBitsToDouble(0xfff0000000000000L)}.
60 public static final double NEGATIVE_INFINITY = -1.0 / 0.0;
63 * A constant holding a Not-a-Number (NaN) value of type
64 * {@code double}. It is equivalent to the value returned by
65 * {@code Double.longBitsToDouble(0x7ff8000000000000L)}.
67 public static final double NaN = 0.0d / 0.0;
70 * A constant holding the largest positive finite value of type
72 * (2-2<sup>-52</sup>)·2<sup>1023</sup>. It is equal to
73 * the hexadecimal floating-point literal
74 * {@code 0x1.fffffffffffffP+1023} and also equal to
75 * {@code Double.longBitsToDouble(0x7fefffffffffffffL)}.
77 public static final double MAX_VALUE = 0x1.fffffffffffffP+1023; // 1.7976931348623157e+308
80 * A constant holding the smallest positive normal value of type
81 * {@code double}, 2<sup>-1022</sup>. It is equal to the
82 * hexadecimal floating-point literal {@code 0x1.0p-1022} and also
83 * equal to {@code Double.longBitsToDouble(0x0010000000000000L)}.
87 public static final double MIN_NORMAL = 0x1.0p-1022; // 2.2250738585072014E-308
90 * A constant holding the smallest positive nonzero value of type
91 * {@code double}, 2<sup>-1074</sup>. It is equal to the
92 * hexadecimal floating-point literal
93 * {@code 0x0.0000000000001P-1022} and also equal to
94 * {@code Double.longBitsToDouble(0x1L)}.
96 public static final double MIN_VALUE = 0x0.0000000000001P-1022; // 4.9e-324
99 * Maximum exponent a finite {@code double} variable may have.
100 * It is equal to the value returned by
101 * {@code Math.getExponent(Double.MAX_VALUE)}.
105 public static final int MAX_EXPONENT = 1023;
108 * Minimum exponent a normalized {@code double} variable may
109 * have. It is equal to the value returned by
110 * {@code Math.getExponent(Double.MIN_NORMAL)}.
114 public static final int MIN_EXPONENT = -1022;
117 * The number of bits used to represent a {@code double} value.
121 public static final int SIZE = 64;
124 * The {@code Class} instance representing the primitive type
129 public static final Class<Double> TYPE = (Class<Double>) Class.getPrimitiveClass("double");
132 * Returns a string representation of the {@code double}
133 * argument. All characters mentioned below are ASCII characters.
135 * <li>If the argument is NaN, the result is the string
137 * <li>Otherwise, the result is a string that represents the sign and
138 * magnitude (absolute value) of the argument. If the sign is negative,
139 * the first character of the result is '{@code -}'
140 * (<code>'\u002D'</code>); if the sign is positive, no sign character
141 * appears in the result. As for the magnitude <i>m</i>:
143 * <li>If <i>m</i> is infinity, it is represented by the characters
144 * {@code "Infinity"}; thus, positive infinity produces the result
145 * {@code "Infinity"} and negative infinity produces the result
146 * {@code "-Infinity"}.
148 * <li>If <i>m</i> is zero, it is represented by the characters
149 * {@code "0.0"}; thus, negative zero produces the result
150 * {@code "-0.0"} and positive zero produces the result
153 * <li>If <i>m</i> is greater than or equal to 10<sup>-3</sup> but less
154 * than 10<sup>7</sup>, then it is represented as the integer part of
155 * <i>m</i>, in decimal form with no leading zeroes, followed by
156 * '{@code .}' (<code>'\u002E'</code>), followed by one or
157 * more decimal digits representing the fractional part of <i>m</i>.
159 * <li>If <i>m</i> is less than 10<sup>-3</sup> or greater than or
160 * equal to 10<sup>7</sup>, then it is represented in so-called
161 * "computerized scientific notation." Let <i>n</i> be the unique
162 * integer such that 10<sup><i>n</i></sup> ≤ <i>m</i> {@literal <}
163 * 10<sup><i>n</i>+1</sup>; then let <i>a</i> be the
164 * mathematically exact quotient of <i>m</i> and
165 * 10<sup><i>n</i></sup> so that 1 ≤ <i>a</i> {@literal <} 10. The
166 * magnitude is then represented as the integer part of <i>a</i>,
167 * as a single decimal digit, followed by '{@code .}'
168 * (<code>'\u002E'</code>), followed by decimal digits
169 * representing the fractional part of <i>a</i>, followed by the
170 * letter '{@code E}' (<code>'\u0045'</code>), followed
171 * by a representation of <i>n</i> as a decimal integer, as
172 * produced by the method {@link Integer#toString(int)}.
175 * How many digits must be printed for the fractional part of
176 * <i>m</i> or <i>a</i>? There must be at least one digit to represent
177 * the fractional part, and beyond that as many, but only as many, more
178 * digits as are needed to uniquely distinguish the argument value from
179 * adjacent values of type {@code double}. That is, suppose that
180 * <i>x</i> is the exact mathematical value represented by the decimal
181 * representation produced by this method for a finite nonzero argument
182 * <i>d</i>. Then <i>d</i> must be the {@code double} value nearest
183 * to <i>x</i>; or if two {@code double} values are equally close
184 * to <i>x</i>, then <i>d</i> must be one of them and the least
185 * significant bit of the significand of <i>d</i> must be {@code 0}.
187 * <p>To create localized string representations of a floating-point
188 * value, use subclasses of {@link java.text.NumberFormat}.
190 * @param d the {@code double} to be converted.
191 * @return a string representation of the argument.
193 @JavaScriptBody(args="d", body="var r = d.toString();"
194 + "if (r.indexOf('.') === -1) r = r + '.0';"
196 public static String toString(double d) {
197 throw new UnsupportedOperationException();
201 * Returns a hexadecimal string representation of the
202 * {@code double} argument. All characters mentioned below
203 * are ASCII characters.
206 * <li>If the argument is NaN, the result is the string
208 * <li>Otherwise, the result is a string that represents the sign
209 * and magnitude of the argument. If the sign is negative, the
210 * first character of the result is '{@code -}'
211 * (<code>'\u002D'</code>); if the sign is positive, no sign
212 * character appears in the result. As for the magnitude <i>m</i>:
215 * <li>If <i>m</i> is infinity, it is represented by the string
216 * {@code "Infinity"}; thus, positive infinity produces the
217 * result {@code "Infinity"} and negative infinity produces
218 * the result {@code "-Infinity"}.
220 * <li>If <i>m</i> is zero, it is represented by the string
221 * {@code "0x0.0p0"}; thus, negative zero produces the result
222 * {@code "-0x0.0p0"} and positive zero produces the result
225 * <li>If <i>m</i> is a {@code double} value with a
226 * normalized representation, substrings are used to represent the
227 * significand and exponent fields. The significand is
228 * represented by the characters {@code "0x1."}
229 * followed by a lowercase hexadecimal representation of the rest
230 * of the significand as a fraction. Trailing zeros in the
231 * hexadecimal representation are removed unless all the digits
232 * are zero, in which case a single zero is used. Next, the
233 * exponent is represented by {@code "p"} followed
234 * by a decimal string of the unbiased exponent as if produced by
235 * a call to {@link Integer#toString(int) Integer.toString} on the
238 * <li>If <i>m</i> is a {@code double} value with a subnormal
239 * representation, the significand is represented by the
240 * characters {@code "0x0."} followed by a
241 * hexadecimal representation of the rest of the significand as a
242 * fraction. Trailing zeros in the hexadecimal representation are
243 * removed. Next, the exponent is represented by
244 * {@code "p-1022"}. Note that there must be at
245 * least one nonzero digit in a subnormal significand.
252 * <caption><h3>Examples</h3></caption>
253 * <tr><th>Floating-point Value</th><th>Hexadecimal String</th>
254 * <tr><td>{@code 1.0}</td> <td>{@code 0x1.0p0}</td>
255 * <tr><td>{@code -1.0}</td> <td>{@code -0x1.0p0}</td>
256 * <tr><td>{@code 2.0}</td> <td>{@code 0x1.0p1}</td>
257 * <tr><td>{@code 3.0}</td> <td>{@code 0x1.8p1}</td>
258 * <tr><td>{@code 0.5}</td> <td>{@code 0x1.0p-1}</td>
259 * <tr><td>{@code 0.25}</td> <td>{@code 0x1.0p-2}</td>
260 * <tr><td>{@code Double.MAX_VALUE}</td>
261 * <td>{@code 0x1.fffffffffffffp1023}</td>
262 * <tr><td>{@code Minimum Normal Value}</td>
263 * <td>{@code 0x1.0p-1022}</td>
264 * <tr><td>{@code Maximum Subnormal Value}</td>
265 * <td>{@code 0x0.fffffffffffffp-1022}</td>
266 * <tr><td>{@code Double.MIN_VALUE}</td>
267 * <td>{@code 0x0.0000000000001p-1022}</td>
269 * @param d the {@code double} to be converted.
270 * @return a hex string representation of the argument.
272 * @author Joseph D. Darcy
274 public static String toHexString(double d) {
275 throw new UnsupportedOperationException();
277 // * Modeled after the "a" conversion specifier in C99, section
278 // * 7.19.6.1; however, the output of this method is more
279 // * tightly specified.
281 // if (!FpUtils.isFinite(d) )
282 // // For infinity and NaN, use the decimal output.
283 // return Double.toString(d);
285 // // Initialized to maximum size of output.
286 // StringBuffer answer = new StringBuffer(24);
288 // if (FpUtils.rawCopySign(1.0, d) == -1.0) // value is negative,
289 // answer.append("-"); // so append sign info
291 // answer.append("0x");
296 // answer.append("0.0p0");
299 // boolean subnormal = (d < DoubleConsts.MIN_NORMAL);
301 // // Isolate significand bits and OR in a high-order bit
302 // // so that the string representation has a known
304 // long signifBits = (Double.doubleToLongBits(d)
305 // & DoubleConsts.SIGNIF_BIT_MASK) |
306 // 0x1000000000000000L;
308 // // Subnormal values have a 0 implicit bit; normal
309 // // values have a 1 implicit bit.
310 // answer.append(subnormal ? "0." : "1.");
312 // // Isolate the low-order 13 digits of the hex
313 // // representation. If all the digits are zero,
314 // // replace with a single 0; otherwise, remove all
315 // // trailing zeros.
316 // String signif = Long.toHexString(signifBits).substring(3,16);
317 // answer.append(signif.equals("0000000000000") ? // 13 zeros
319 // signif.replaceFirst("0{1,12}$", ""));
321 // // If the value is subnormal, use the E_min exponent
322 // // value for double; otherwise, extract and report d's
323 // // exponent (the representation of a subnormal uses
325 // answer.append("p" + (subnormal ?
326 // DoubleConsts.MIN_EXPONENT:
327 // FpUtils.getExponent(d) ));
329 // return answer.toString();
334 * Returns a {@code Double} object holding the
335 * {@code double} value represented by the argument string
338 * <p>If {@code s} is {@code null}, then a
339 * {@code NullPointerException} is thrown.
341 * <p>Leading and trailing whitespace characters in {@code s}
342 * are ignored. Whitespace is removed as if by the {@link
343 * String#trim} method; that is, both ASCII space and control
344 * characters are removed. The rest of {@code s} should
345 * constitute a <i>FloatValue</i> as described by the lexical
350 * <dt><i>FloatValue:</i>
351 * <dd><i>Sign<sub>opt</sub></i> {@code NaN}
352 * <dd><i>Sign<sub>opt</sub></i> {@code Infinity}
353 * <dd><i>Sign<sub>opt</sub> FloatingPointLiteral</i>
354 * <dd><i>Sign<sub>opt</sub> HexFloatingPointLiteral</i>
355 * <dd><i>SignedInteger</i>
361 * <dt><i>HexFloatingPointLiteral</i>:
362 * <dd> <i>HexSignificand BinaryExponent FloatTypeSuffix<sub>opt</sub></i>
368 * <dt><i>HexSignificand:</i>
369 * <dd><i>HexNumeral</i>
370 * <dd><i>HexNumeral</i> {@code .}
371 * <dd>{@code 0x} <i>HexDigits<sub>opt</sub>
372 * </i>{@code .}<i> HexDigits</i>
373 * <dd>{@code 0X}<i> HexDigits<sub>opt</sub>
374 * </i>{@code .} <i>HexDigits</i>
380 * <dt><i>BinaryExponent:</i>
381 * <dd><i>BinaryExponentIndicator SignedInteger</i>
387 * <dt><i>BinaryExponentIndicator:</i>
394 * where <i>Sign</i>, <i>FloatingPointLiteral</i>,
395 * <i>HexNumeral</i>, <i>HexDigits</i>, <i>SignedInteger</i> and
396 * <i>FloatTypeSuffix</i> are as defined in the lexical structure
398 * <cite>The Java™ Language Specification</cite>,
399 * except that underscores are not accepted between digits.
400 * If {@code s} does not have the form of
401 * a <i>FloatValue</i>, then a {@code NumberFormatException}
402 * is thrown. Otherwise, {@code s} is regarded as
403 * representing an exact decimal value in the usual
404 * "computerized scientific notation" or as an exact
405 * hexadecimal value; this exact numerical value is then
406 * conceptually converted to an "infinitely precise"
407 * binary value that is then rounded to type {@code double}
408 * by the usual round-to-nearest rule of IEEE 754 floating-point
409 * arithmetic, which includes preserving the sign of a zero
412 * Note that the round-to-nearest rule also implies overflow and
413 * underflow behaviour; if the exact value of {@code s} is large
414 * enough in magnitude (greater than or equal to ({@link
415 * #MAX_VALUE} + {@link Math#ulp(double) ulp(MAX_VALUE)}/2),
416 * rounding to {@code double} will result in an infinity and if the
417 * exact value of {@code s} is small enough in magnitude (less
418 * than or equal to {@link #MIN_VALUE}/2), rounding to float will
421 * Finally, after rounding a {@code Double} object representing
422 * this {@code double} value is returned.
424 * <p> To interpret localized string representations of a
425 * floating-point value, use subclasses of {@link
426 * java.text.NumberFormat}.
428 * <p>Note that trailing format specifiers, specifiers that
429 * determine the type of a floating-point literal
430 * ({@code 1.0f} is a {@code float} value;
431 * {@code 1.0d} is a {@code double} value), do
432 * <em>not</em> influence the results of this method. In other
433 * words, the numerical value of the input string is converted
434 * directly to the target floating-point type. The two-step
435 * sequence of conversions, string to {@code float} followed
436 * by {@code float} to {@code double}, is <em>not</em>
437 * equivalent to converting a string directly to
438 * {@code double}. For example, the {@code float}
439 * literal {@code 0.1f} is equal to the {@code double}
440 * value {@code 0.10000000149011612}; the {@code float}
441 * literal {@code 0.1f} represents a different numerical
442 * value than the {@code double} literal
443 * {@code 0.1}. (The numerical value 0.1 cannot be exactly
444 * represented in a binary floating-point number.)
446 * <p>To avoid calling this method on an invalid string and having
447 * a {@code NumberFormatException} be thrown, the regular
448 * expression below can be used to screen the input string:
452 * final String Digits = "(\\p{Digit}+)";
453 * final String HexDigits = "(\\p{XDigit}+)";
454 * // an exponent is 'e' or 'E' followed by an optionally
455 * // signed decimal integer.
456 * final String Exp = "[eE][+-]?"+Digits;
457 * final String fpRegex =
458 * ("[\\x00-\\x20]*"+ // Optional leading "whitespace"
459 * "[+-]?(" + // Optional sign character
460 * "NaN|" + // "NaN" string
461 * "Infinity|" + // "Infinity" string
463 * // A decimal floating-point string representing a finite positive
464 * // number without a leading sign has at most five basic pieces:
465 * // Digits . Digits ExponentPart FloatTypeSuffix
467 * // Since this method allows integer-only strings as input
468 * // in addition to strings of floating-point literals, the
469 * // two sub-patterns below are simplifications of the grammar
470 * // productions from section 3.10.2 of
471 * // <cite>The Java™ Language Specification</cite>.
473 * // Digits ._opt Digits_opt ExponentPart_opt FloatTypeSuffix_opt
474 * "((("+Digits+"(\\.)?("+Digits+"?)("+Exp+")?)|"+
476 * // . Digits ExponentPart_opt FloatTypeSuffix_opt
477 * "(\\.("+Digits+")("+Exp+")?)|"+
479 * // Hexadecimal strings
481 * // 0[xX] HexDigits ._opt BinaryExponent FloatTypeSuffix_opt
482 * "(0[xX]" + HexDigits + "(\\.)?)|" +
484 * // 0[xX] HexDigits_opt . HexDigits BinaryExponent FloatTypeSuffix_opt
485 * "(0[xX]" + HexDigits + "?(\\.)" + HexDigits + ")" +
487 * ")[pP][+-]?" + Digits + "))" +
489 * "[\\x00-\\x20]*");// Optional trailing "whitespace"
491 * if (Pattern.matches(fpRegex, myString))
492 * Double.valueOf(myString); // Will not throw NumberFormatException
494 * // Perform suitable alternative action
499 * @param s the string to be parsed.
500 * @return a {@code Double} object holding the value
501 * represented by the {@code String} argument.
502 * @throws NumberFormatException if the string does not contain a
505 @JavaScriptBody(args="s", body="return parseFloat(s);")
506 public static Double valueOf(String s) throws NumberFormatException {
507 throw new UnsupportedOperationException();
508 // return new Double(FloatingDecimal.readJavaFormatString(s).doubleValue());
512 * Returns a {@code Double} instance representing the specified
513 * {@code double} value.
514 * If a new {@code Double} instance is not required, this method
515 * should generally be used in preference to the constructor
516 * {@link #Double(double)}, as this method is likely to yield
517 * significantly better space and time performance by caching
518 * frequently requested values.
520 * @param d a double value.
521 * @return a {@code Double} instance representing {@code d}.
524 public static Double valueOf(double d) {
525 return new Double(d);
529 * Returns a new {@code double} initialized to the value
530 * represented by the specified {@code String}, as performed
531 * by the {@code valueOf} method of class
534 * @param s the string to be parsed.
535 * @return the {@code double} value represented by the string
537 * @throws NullPointerException if the string is null
538 * @throws NumberFormatException if the string does not contain
539 * a parsable {@code double}.
540 * @see java.lang.Double#valueOf(String)
543 @JavaScriptBody(args="s", body="return parseFloat(s);")
544 public static double parseDouble(String s) throws NumberFormatException {
545 throw new UnsupportedOperationException();
546 // return FloatingDecimal.readJavaFormatString(s).doubleValue();
550 * Returns {@code true} if the specified number is a
551 * Not-a-Number (NaN) value, {@code false} otherwise.
553 * @param v the value to be tested.
554 * @return {@code true} if the value of the argument is NaN;
555 * {@code false} otherwise.
557 static public boolean isNaN(double v) {
562 * Returns {@code true} if the specified number is infinitely
563 * large in magnitude, {@code false} otherwise.
565 * @param v the value to be tested.
566 * @return {@code true} if the value of the argument is positive
567 * infinity or negative infinity; {@code false} otherwise.
569 static public boolean isInfinite(double v) {
570 return (v == POSITIVE_INFINITY) || (v == NEGATIVE_INFINITY);
574 * The value of the Double.
578 private final double value;
581 * Constructs a newly allocated {@code Double} object that
582 * represents the primitive {@code double} argument.
584 * @param value the value to be represented by the {@code Double}.
586 public Double(double value) {
591 * Constructs a newly allocated {@code Double} object that
592 * represents the floating-point value of type {@code double}
593 * represented by the string. The string is converted to a
594 * {@code double} value as if by the {@code valueOf} method.
596 * @param s a string to be converted to a {@code Double}.
597 * @throws NumberFormatException if the string does not contain a
599 * @see java.lang.Double#valueOf(java.lang.String)
601 public Double(String s) throws NumberFormatException {
602 // REMIND: this is inefficient
603 this(valueOf(s).doubleValue());
607 * Returns {@code true} if this {@code Double} value is
608 * a Not-a-Number (NaN), {@code false} otherwise.
610 * @return {@code true} if the value represented by this object is
611 * NaN; {@code false} otherwise.
613 public boolean isNaN() {
618 * Returns {@code true} if this {@code Double} value is
619 * infinitely large in magnitude, {@code false} otherwise.
621 * @return {@code true} if the value represented by this object is
622 * positive infinity or negative infinity;
623 * {@code false} otherwise.
625 public boolean isInfinite() {
626 return isInfinite(value);
630 * Returns a string representation of this {@code Double} object.
631 * The primitive {@code double} value represented by this
632 * object is converted to a string exactly as if by the method
633 * {@code toString} of one argument.
635 * @return a {@code String} representation of this object.
636 * @see java.lang.Double#toString(double)
638 public String toString() {
639 return toString(value);
643 * Returns the value of this {@code Double} as a {@code byte} (by
644 * casting to a {@code byte}).
646 * @return the {@code double} value represented by this object
647 * converted to type {@code byte}
650 public byte byteValue() {
655 * Returns the value of this {@code Double} as a
656 * {@code short} (by casting to a {@code short}).
658 * @return the {@code double} value represented by this object
659 * converted to type {@code short}
662 public short shortValue() {
667 * Returns the value of this {@code Double} as an
668 * {@code int} (by casting to type {@code int}).
670 * @return the {@code double} value represented by this object
671 * converted to type {@code int}
673 public int intValue() {
678 * Returns the value of this {@code Double} as a
679 * {@code long} (by casting to type {@code long}).
681 * @return the {@code double} value represented by this object
682 * converted to type {@code long}
684 public long longValue() {
689 * Returns the {@code float} value of this
690 * {@code Double} object.
692 * @return the {@code double} value represented by this object
693 * converted to type {@code float}
696 public float floatValue() {
701 * Returns the {@code double} value of this
702 * {@code Double} object.
704 * @return the {@code double} value represented by this object
706 public double doubleValue() {
707 return (double)value;
711 * Returns a hash code for this {@code Double} object. The
712 * result is the exclusive OR of the two halves of the
713 * {@code long} integer bit representation, exactly as
714 * produced by the method {@link #doubleToLongBits(double)}, of
715 * the primitive {@code double} value represented by this
716 * {@code Double} object. That is, the hash code is the value
720 * {@code (int)(v^(v>>>32))}
723 * where {@code v} is defined by:
726 * {@code long v = Double.doubleToLongBits(this.doubleValue());}
729 * @return a {@code hash code} value for this object.
731 public int hashCode() {
732 long bits = doubleToLongBits(value);
733 return (int)(bits ^ (bits >>> 32));
737 * Compares this object against the specified object. The result
738 * is {@code true} if and only if the argument is not
739 * {@code null} and is a {@code Double} object that
740 * represents a {@code double} that has the same value as the
741 * {@code double} represented by this object. For this
742 * purpose, two {@code double} values are considered to be
743 * the same if and only if the method {@link
744 * #doubleToLongBits(double)} returns the identical
745 * {@code long} value when applied to each.
747 * <p>Note that in most cases, for two instances of class
748 * {@code Double}, {@code d1} and {@code d2}, the
749 * value of {@code d1.equals(d2)} is {@code true} if and
753 * {@code d1.doubleValue() == d2.doubleValue()}
756 * <p>also has the value {@code true}. However, there are two
759 * <li>If {@code d1} and {@code d2} both represent
760 * {@code Double.NaN}, then the {@code equals} method
761 * returns {@code true}, even though
762 * {@code Double.NaN==Double.NaN} has the value
764 * <li>If {@code d1} represents {@code +0.0} while
765 * {@code d2} represents {@code -0.0}, or vice versa,
766 * the {@code equal} test has the value {@code false},
767 * even though {@code +0.0==-0.0} has the value {@code true}.
769 * This definition allows hash tables to operate properly.
770 * @param obj the object to compare with.
771 * @return {@code true} if the objects are the same;
772 * {@code false} otherwise.
773 * @see java.lang.Double#doubleToLongBits(double)
775 public boolean equals(Object obj) {
776 return (obj instanceof Double)
777 && (((Double)obj).value) == value;
781 * Returns a representation of the specified floating-point value
782 * according to the IEEE 754 floating-point "double
783 * format" bit layout.
785 * <p>Bit 63 (the bit that is selected by the mask
786 * {@code 0x8000000000000000L}) represents the sign of the
787 * floating-point number. Bits
788 * 62-52 (the bits that are selected by the mask
789 * {@code 0x7ff0000000000000L}) represent the exponent. Bits 51-0
790 * (the bits that are selected by the mask
791 * {@code 0x000fffffffffffffL}) represent the significand
792 * (sometimes called the mantissa) of the floating-point number.
794 * <p>If the argument is positive infinity, the result is
795 * {@code 0x7ff0000000000000L}.
797 * <p>If the argument is negative infinity, the result is
798 * {@code 0xfff0000000000000L}.
800 * <p>If the argument is NaN, the result is
801 * {@code 0x7ff8000000000000L}.
803 * <p>In all cases, the result is a {@code long} integer that, when
804 * given to the {@link #longBitsToDouble(long)} method, will produce a
805 * floating-point value the same as the argument to
806 * {@code doubleToLongBits} (except all NaN values are
807 * collapsed to a single "canonical" NaN value).
809 * @param value a {@code double} precision floating-point number.
810 * @return the bits that represent the floating-point number.
812 public static long doubleToLongBits(double value) {
813 throw new UnsupportedOperationException();
814 // long result = doubleToRawLongBits(value);
815 // // Check for NaN based on values of bit fields, maximum
816 // // exponent and nonzero significand.
817 // if ( ((result & DoubleConsts.EXP_BIT_MASK) ==
818 // DoubleConsts.EXP_BIT_MASK) &&
819 // (result & DoubleConsts.SIGNIF_BIT_MASK) != 0L)
820 // result = 0x7ff8000000000000L;
825 * Returns a representation of the specified floating-point value
826 * according to the IEEE 754 floating-point "double
827 * format" bit layout, preserving Not-a-Number (NaN) values.
829 * <p>Bit 63 (the bit that is selected by the mask
830 * {@code 0x8000000000000000L}) represents the sign of the
831 * floating-point number. Bits
832 * 62-52 (the bits that are selected by the mask
833 * {@code 0x7ff0000000000000L}) represent the exponent. Bits 51-0
834 * (the bits that are selected by the mask
835 * {@code 0x000fffffffffffffL}) represent the significand
836 * (sometimes called the mantissa) of the floating-point number.
838 * <p>If the argument is positive infinity, the result is
839 * {@code 0x7ff0000000000000L}.
841 * <p>If the argument is negative infinity, the result is
842 * {@code 0xfff0000000000000L}.
844 * <p>If the argument is NaN, the result is the {@code long}
845 * integer representing the actual NaN value. Unlike the
846 * {@code doubleToLongBits} method,
847 * {@code doubleToRawLongBits} does not collapse all the bit
848 * patterns encoding a NaN to a single "canonical" NaN
851 * <p>In all cases, the result is a {@code long} integer that,
852 * when given to the {@link #longBitsToDouble(long)} method, will
853 * produce a floating-point value the same as the argument to
854 * {@code doubleToRawLongBits}.
856 * @param value a {@code double} precision floating-point number.
857 * @return the bits that represent the floating-point number.
860 public static native long doubleToRawLongBits(double value);
863 * Returns the {@code double} value corresponding to a given
864 * bit representation.
865 * The argument is considered to be a representation of a
866 * floating-point value according to the IEEE 754 floating-point
867 * "double format" bit layout.
869 * <p>If the argument is {@code 0x7ff0000000000000L}, the result
870 * is positive infinity.
872 * <p>If the argument is {@code 0xfff0000000000000L}, the result
873 * is negative infinity.
875 * <p>If the argument is any value in the range
876 * {@code 0x7ff0000000000001L} through
877 * {@code 0x7fffffffffffffffL} or in the range
878 * {@code 0xfff0000000000001L} through
879 * {@code 0xffffffffffffffffL}, the result is a NaN. No IEEE
880 * 754 floating-point operation provided by Java can distinguish
881 * between two NaN values of the same type with different bit
882 * patterns. Distinct values of NaN are only distinguishable by
883 * use of the {@code Double.doubleToRawLongBits} method.
885 * <p>In all other cases, let <i>s</i>, <i>e</i>, and <i>m</i> be three
886 * values that can be computed from the argument:
889 * int s = ((bits >> 63) == 0) ? 1 : -1;
890 * int e = (int)((bits >> 52) & 0x7ffL);
891 * long m = (e == 0) ?
892 * (bits & 0xfffffffffffffL) << 1 :
893 * (bits & 0xfffffffffffffL) | 0x10000000000000L;
894 * </pre></blockquote>
896 * Then the floating-point result equals the value of the mathematical
897 * expression <i>s</i>·<i>m</i>·2<sup><i>e</i>-1075</sup>.
899 * <p>Note that this method may not be able to return a
900 * {@code double} NaN with exactly same bit pattern as the
901 * {@code long} argument. IEEE 754 distinguishes between two
902 * kinds of NaNs, quiet NaNs and <i>signaling NaNs</i>. The
903 * differences between the two kinds of NaN are generally not
904 * visible in Java. Arithmetic operations on signaling NaNs turn
905 * them into quiet NaNs with a different, but often similar, bit
906 * pattern. However, on some processors merely copying a
907 * signaling NaN also performs that conversion. In particular,
908 * copying a signaling NaN to return it to the calling method
909 * may perform this conversion. So {@code longBitsToDouble}
910 * may not be able to return a {@code double} with a
911 * signaling NaN bit pattern. Consequently, for some
912 * {@code long} values,
913 * {@code doubleToRawLongBits(longBitsToDouble(start))} may
914 * <i>not</i> equal {@code start}. Moreover, which
915 * particular bit patterns represent signaling NaNs is platform
916 * dependent; although all NaN bit patterns, quiet or signaling,
917 * must be in the NaN range identified above.
919 * @param bits any {@code long} integer.
920 * @return the {@code double} floating-point value with the same
923 public static native double longBitsToDouble(long bits);
926 * Compares two {@code Double} objects numerically. There
927 * are two ways in which comparisons performed by this method
928 * differ from those performed by the Java language numerical
929 * comparison operators ({@code <, <=, ==, >=, >})
930 * when applied to primitive {@code double} values:
932 * {@code Double.NaN} is considered by this method
933 * to be equal to itself and greater than all other
934 * {@code double} values (including
935 * {@code Double.POSITIVE_INFINITY}).
937 * {@code 0.0d} is considered by this method to be greater
938 * than {@code -0.0d}.
940 * This ensures that the <i>natural ordering</i> of
941 * {@code Double} objects imposed by this method is <i>consistent
944 * @param anotherDouble the {@code Double} to be compared.
945 * @return the value {@code 0} if {@code anotherDouble} is
946 * numerically equal to this {@code Double}; a value
947 * less than {@code 0} if this {@code Double}
948 * is numerically less than {@code anotherDouble};
949 * and a value greater than {@code 0} if this
950 * {@code Double} is numerically greater than
951 * {@code anotherDouble}.
955 public int compareTo(Double anotherDouble) {
956 return Double.compare(value, anotherDouble.value);
960 * Compares the two specified {@code double} values. The sign
961 * of the integer value returned is the same as that of the
962 * integer that would be returned by the call:
964 * new Double(d1).compareTo(new Double(d2))
967 * @param d1 the first {@code double} to compare
968 * @param d2 the second {@code double} to compare
969 * @return the value {@code 0} if {@code d1} is
970 * numerically equal to {@code d2}; a value less than
971 * {@code 0} if {@code d1} is numerically less than
972 * {@code d2}; and a value greater than {@code 0}
973 * if {@code d1} is numerically greater than
977 public static int compare(double d1, double d2) {
979 return -1; // Neither val is NaN, thisVal is smaller
981 return 1; // Neither val is NaN, thisVal is larger
983 // Cannot use doubleToRawLongBits because of possibility of NaNs.
984 long thisBits = Double.doubleToLongBits(d1);
985 long anotherBits = Double.doubleToLongBits(d2);
987 return (thisBits == anotherBits ? 0 : // Values are equal
988 (thisBits < anotherBits ? -1 : // (-0.0, 0.0) or (!NaN, NaN)
989 1)); // (0.0, -0.0) or (NaN, !NaN)
992 /** use serialVersionUID from JDK 1.0.2 for interoperability */
993 private static final long serialVersionUID = -9172774392245257468L;