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/*

This is not an official specification document, and usage is restricted.

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(c) 2005-2007 Sun Microsystems, Inc. All Rights Reserved.

Neither this file nor any files generated from it describe a complete specification, and they may only be used as described below. For example, no permission is given for you to incorporate this file, in whole or in part, in an implementation of a Java specification.

Sun Microsystems Inc. owns the copyright in this file and it is provided to you for informative, as opposed to normative, use. The file and any files generated from it may be used to generate other informative documentation, such as a unified set of documents of API signatures for a platform that includes technologies expressed as Java APIs. The file may also be used to produce "compilation stubs," which allow applications to be compiled and validated for such platforms.

Any work generated from this file, such as unified javadocs or compiled stub files, must be accompanied by this notice in its entirety.

This work corresponds to the API signatures of JSR 219: Foundation Profile 1.1. In the event of a discrepency between this work and the JSR 219 specification, which is available at http://www.jcp.org/en/jsr/detail?id=219, the latter takes precedence. */ package java.lang; /** * The Double class wraps a value of the primitive type * double in an object. An object of type * Double contains a single field whose type is * double. *

* In addition, this class provides several methods for converting a * double to a String and a * String to a double, as well as other * constants and methods useful when dealing with a * double. * * @author Lee Boynton * @author Arthur van Hoff * @version 1.82, 01/23/03 * @since JDK1.0 */ public final class Double extends java.lang.Number implements java.lang.Comparable { /** * A constant holding the positive infinity of type * double. It is equal to the value returned by * Double.longBitsToDouble(0x7ff0000000000000L). */ public static final double POSITIVE_INFINITY = 1d/0d; /** * A constant holding the negative infinity of type * double. It is equal to the value returned by * Double.longBitsToDouble(0xfff0000000000000L). */ public static final double NEGATIVE_INFINITY = -1d/0d; /** * A constant holding a Not-a-Number (NaN) value of type * double. It is equivalent to the value returned by * Double.longBitsToDouble(0x7ff8000000000000L). */ public static final double NaN = 0d/0d; /** * A constant holding the largest positive finite value of type * double, (2-2-52)·21023. * It is equal to the value returned by: * Double.longBitsToDouble(0x7fefffffffffffffL). */ public static final double MAX_VALUE = 1.7976931348623157E308; /** * A constant holding the smallest positive nonzero value of type * double, 2-1074. It is equal to the * value returned by Double.longBitsToDouble(0x1L). */ public static final double MIN_VALUE = longBitsToDouble(1L); /** * The Class instance representing the primitive type * double. * * @since JDK1.1 */ public static final java.lang.Class TYPE = null; /** * The value of the Double. * * @serial */ private double value; /** * Constructs a newly allocated Double object that * represents the primitive double argument. * * @param value the value to be represented by the Double. */ public Double(double value) { } /** * Constructs a newly allocated Double object that * represents the floating-point value of type double * represented by the string. The string is converted to a * double value as if by the valueOf method. * * @param s a string to be converted to a Double. * @exception NumberFormatException if the string does not contain a * parsable number. * @see java.lang.Double#valueOf(java.lang.String) */ public Double(java.lang.String s) throws java.lang.NumberFormatException { } /** * Returns a string representation of the double * argument. All characters mentioned below are ASCII characters. *

    *
  • If the argument is NaN, the result is the string * "NaN". *
  • 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 '-' * ('\u002D'); if the sign is positive, no sign character * appears in the result. As for the magnitude m: *
      *
    • If m is infinity, it is represented by the characters * "Infinity"; thus, positive infinity produces the result * "Infinity" and negative infinity produces the result * "-Infinity". * *
    • If m is zero, it is represented by the characters * "0.0"; thus, negative zero produces the result * "-0.0" and positive zero produces the result * "0.0". * *
    • If m is greater than or equal to 10-3 but less * than 107, then it is represented as the integer part of * m, in decimal form with no leading zeroes, followed by * '.' ('\u002E'), followed by one or * more decimal digits representing the fractional part of m. * *
    • If m is less than 10-3 or greater than or * equal to 107, then it is represented in so-called * "computerized scientific notation." Let n be the unique * integer such that 10n <= m < * 10n+1; then let a be the * mathematically exact quotient of m and * 10n so that 1 <= a < 10. The * magnitude is then represented as the integer part of a, * as a single decimal digit, followed by '.' * ('\u002E'), followed by decimal digits * representing the fractional part of a, followed by the * letter 'E' ('\u0045'), followed * by a representation of n as a decimal integer, as * produced by the method {@link Integer#toString(int)}. *
    *
* 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 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 double value nearest * to x; or if two 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 0. *

* To create localized string representations of a floating-point * value, use subclasses of {@link java.text.NumberFormat}. * * @param d the double to be converted. * @return a string representation of the argument. */ public static java.lang.String toString(double d) { return null; } /** * Returns a Double object holding the * double value represented by the argument string * s. *

* If s is null, then a * NullPointerException is thrown. *

* Leading and trailing whitespace characters in s * are ignored. The rest of s should constitute a * FloatValue as described by the lexical rule: *

*
*
FloatValue: *
Signopt NaN *
Signopt Infinity *
Signopt FloatingPointLiteral *
*
* where Sign and FloatingPointLiteral are as * defined in *
§3.10.2 * of the Java * Language Specification. If s does not have the * form of a FloatValue, then a NumberFormatException * is thrown. Otherwise, s is regarded as * representing an exact decimal value in the usual "computerized * scientific notation"; this exact decimal value is then * conceptually converted to an "infinitely precise" binary value * that is then rounded to type double by the usual * round-to-nearest rule of IEEE 754 floating-point arithmetic, * which includes preserving the sign of a zero value. Finally, a * Double object representing this * 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 * (1.0f is a float value; * 1.0d is a 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 float followed * by float to double, is not * equivalent to converting a string directly to * double. For example, the float * literal 0.1f is equal to the double * value 0.10000000149011612; the float * literal 0.1f represents a different numerical * value than the double literal * 0.1. (The numerical value 0.1 cannot be exactly * represented in a binary floating-point number.) * * @param s the string to be parsed. * @return a Double object holding the value * represented by the String argument. * @exception NumberFormatException if the string does not contain a * parsable number. */ public static java.lang.Double valueOf(java.lang.String s) throws java.lang.NumberFormatException { return null; } /** * Returns a new double initialized to the value * represented by the specified String, as performed * by the valueOf method of class * Double. * * @param s the string to be parsed. * @return the double value represented by the string * argument. * @exception NumberFormatException if the string does not contain * a parsable double. * @see java.lang.Double#valueOf(String) * @since 1.2 */ public static double parseDouble(java.lang.String s) throws java.lang.NumberFormatException { return 0.0d; } /** * Returns true if the specified number is a * Not-a-Number (NaN) value, false otherwise. * * @param v the value to be tested. * @return true if the value of the argument is NaN; * false otherwise. */ public static boolean isNaN(double v) { return false; } /** * Returns true if the specified number is infinitely * large in magnitude, false otherwise. * * @param v the value to be tested. * @return true if the value of the argument is positive * infinity or negative infinity; false otherwise. */ public static boolean isInfinite(double v) { return false; } /** * Returns true if this Double value is * a Not-a-Number (NaN), false otherwise. * * @return true if the value represented by this object is * NaN; false otherwise. */ public boolean isNaN() { return false; } /** * Returns true if this Double value is * infinitely large in magnitude, false otherwise. * * @return true if the value represented by this object is * positive infinity or negative infinity; * false otherwise. */ public boolean isInfinite() { return false; } /** * Returns a string representation of this Double object. * The primitive double value represented by this * object is converted to a string exactly as if by the method * toString of one argument. * * @return a String representation of this object. * @see java.lang.Double#toString(double) */ public java.lang.String toString() { return null; } /** * Returns the value of this Double as a byte (by * casting to a byte). * * @return the double value represented by this object * converted to type byte * @since JDK1.1 */ public byte byteValue() { return ' '; } /** * Returns the value of this Double as a * short (by casting to a short). * * @return the double value represented by this object * converted to type short * @since JDK1.1 */ public short shortValue() { return -1; } /** * Returns the value of this Double as an * int (by casting to type int). * * @return the double value represented by this object * converted to type int */ public int intValue() { return 0; } /** * Returns the value of this Double as a * long (by casting to type long). * * @return the double value represented by this object * converted to type long */ public long longValue() { return -1; } /** * Returns the float value of this * Double object. * * @return the double value represented by this object * converted to type float * @since JDK1.0 */ public float floatValue() { return 0.0f; } /** * Returns the double value of this * Double object. * * @return the double value represented by this object */ public double doubleValue() { return 0.0d; } /** * Returns a hash code for this Double object. The * result is the exclusive OR of the two halves of the * long integer bit representation, exactly as * produced by the method {@link #doubleToLongBits(double)}, of * the primitive double value represented by this * Double object. That is, the hash code is the value * of the expression: *

     * (int)(v^(v>>>32))
     * 
* where v is defined by: *
     * long v = Double.doubleToLongBits(this.doubleValue());
     * 
* * @return a hash code value for this object. */ public int hashCode() { return 0; } /** * Compares this object against the specified object. The result * is true if and only if the argument is not * null and is a Double object that * represents a double that has the same value as the * double represented by this object. For this * purpose, two double values are considered to be * the same if and only if the method {@link * #doubleToLongBits(double)} returns the identical * long value when applied to each. *

* Note that in most cases, for two instances of class * Double, d1 and d2, the * value of d1.equals(d2) is true if and * only if *

     *   d1.doubleValue() == d2.doubleValue()
     * 
*

* also has the value true. However, there are two * exceptions: *

    *
  • If d1 and d2 both represent * Double.NaN, then the equals method * returns true, even though * Double.NaN==Double.NaN has the value * false. *
  • If d1 represents +0.0 while * d2 represents -0.0, or vice versa, * the equal test has the value false, * even though +0.0==-0.0 has the value true. *
* This definition allows hash tables to operate properly. * @param obj the object to compare with. * @return true if the objects are the same; * false otherwise. * @see java.lang.Double#doubleToLongBits(double) */ public boolean equals(java.lang.Object obj) { return false; } /** * 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 * 0x8000000000000000L) represents the sign of the * floating-point number. Bits * 62-52 (the bits that are selected by the mask * 0x7ff0000000000000L) represent the exponent. Bits 51-0 * (the bits that are selected by the mask * 0x000fffffffffffffL) represent the significand * (sometimes called the mantissa) of the floating-point number. *

* If the argument is positive infinity, the result is * 0x7ff0000000000000L. *

* If the argument is negative infinity, the result is * 0xfff0000000000000L. *

* If the argument is NaN, the result is * 0x7ff8000000000000L. *

* In all cases, the result is a long integer that, when * given to the {@link #longBitsToDouble(long)} method, will produce a * floating-point value the same as the argument to * doubleToLongBits (except all NaN values are * collapsed to a single "canonical" NaN value). * * @param value a double precision floating-point number. * @return the bits that represent the floating-point number. */ public static long doubleToLongBits(double value) { return -1; } /** * 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 * 0x8000000000000000L) represents the sign of the * floating-point number. Bits * 62-52 (the bits that are selected by the mask * 0x7ff0000000000000L) represent the exponent. Bits 51-0 * (the bits that are selected by the mask * 0x000fffffffffffffL) represent the significand * (sometimes called the mantissa) of the floating-point number. *

* If the argument is positive infinity, the result is * 0x7ff0000000000000L. *

* If the argument is negative infinity, the result is * 0xfff0000000000000L. *

* If the argument is NaN, the result is the long * integer representing the actual NaN value. Unlike the * doubleToLongBits method, * doubleToRawLongBits does not collapse all the bit * patterns encoding a NaN to a single "canonical" NaN * value. *

* In all cases, the result is a long integer that, * when given to the {@link #longBitsToDouble(long)} method, will * produce a floating-point value the same as the argument to * doubleToRawLongBits. * * @param value a double precision floating-point number. * @return the bits that represent the floating-point number. */ public static long doubleToRawLongBits(double value) { return -1; } /** * Returns the 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 0x7ff0000000000000L, the result * is positive infinity. *

* If the argument is 0xfff0000000000000L, the result * is negative infinity. *

* If the argument is any value in the range * 0x7ff0000000000001L through * 0x7fffffffffffffffL or in the range * 0xfff0000000000001L through * 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 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 * double NaN with exactly same bit pattern as the * 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 longBitsToDouble * may not be able to return a double with a * signaling NaN bit pattern. Consequently, for some * long values, * doubleToRawLongBits(longBitsToDouble(start)) may * not equal 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 long integer. * @return the double floating-point value with the same * bit pattern. */ public static double longBitsToDouble(long bits) { return 0.0d; } /** * Compares two 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 (<, <=, ==, >= >) * when applied to primitive double values: *

  • * Double.NaN is considered by this method * to be equal to itself and greater than all other * double values (including * Double.POSITIVE_INFINITY). *
  • * 0.0d is considered by this method to be greater * than -0.0d. *
* This ensures that Double.compareTo(Object) (which * forwards its behavior to this method) obeys the general * contract for Comparable.compareTo, and that the * natural order on Doubles is consistent * with equals. * * @param anotherDouble the Double to be compared. * @return the value 0 if anotherDouble is * numerically equal to this Double; a value * less than 0 if this Double * is numerically less than anotherDouble; * and a value greater than 0 if this * Double is numerically greater than * anotherDouble. * * @since 1.2 * @see Comparable#compareTo(Object) */ public int compareTo(java.lang.Double anotherDouble) { return 0; } /** * Compares this Double object to another object. If * the object is a Double, this function behaves like * compareTo(Double). Otherwise, it throws a * ClassCastException (as Double objects * are comparable only to other Double objects). * * @param o the Object to be compared. * @return the value 0 if the argument is a * Double numerically equal to this * Double; a value less than 0 * if the argument is a Double numerically * greater than this Double; and a value * greater than 0 if the argument is a * Double numerically less than this * Double. * @exception ClassCastException if the argument is not a * Double. * @see java.lang.Comparable * @since 1.2 */ public int compareTo(java.lang.Object o) { return 0; } /** * Compares the two specified 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 double to compare * @param d2 the second double to compare * @return the value 0 if d1 is * numerically equal to d2; a value less than * 0 if d1 is numerically less than * d2; and a value greater than 0 * if d1 is numerically greater than * d2. * @since 1.4 */ public static int compare(double d1, double d2) { return 0; } /** use serialVersionUID from JDK 1.0.2 for interoperability */ private static final long serialVersionUID = -9172774392245257468L; }




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