java.lang.Double Maven / Gradle / Ivy
/*
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stub files, must be accompanied by this notice in its entirety.
This work corresponds to the API signatures of JSR 219: Foundation
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*/
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 Double
s 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;
}