java.lang.Object
|
+----java.lang.Number
|
+----java.lang.Double
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.
double.
double.
double.
double.
double.
Double object that
represents the primitive double argument.
Double object that
represents the floating- point value of type double
represented by the string.
double
argument.
public static final double POSITIVE_INFINITY
double.
public static final double NEGATIVE_INFINITY
double.
public static final double NaN
double.
public static final double MAX_VALUE
double.
public static final double MIN_VALUE
double.
public static final Class TYPE
public Double(double value)
Double object that
represents the primitive double argument.
Double.
public Double(String s) throws NumberFormatException
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.
Double.
public static String toString(double d)
double
argument.
The values NaN, NEGATIVE_INFINITY,
POSITIVE_INFINITY, -0.0, and
+0.0 are represented by the strings
"NaN", "-Infinity",
"Infinity", "-0.0", and
"0.0", respectively.
If d is in the range
10-3 <= |d| <=107,
then it is converted to a string in the style
[-]ddd.ddd. Otherwise, it is converted to a
string in the style [-]m.ddddE±xx.
There is always a minimum of one digit after the decimal point.
The number of digits is the minimum needed to uniquely distinguish
the argument value from adjacent values of type
double.
public static Double valueOf(String s) throws NumberFormatException
Double initialized to the
value represented by the string argument.
public static boolean isNaN(double v)
true if the value of the argument is NaN;
false otherwise.
public static boolean isInfinite(double v)
true if the value of the argument is positive
infinity or negative infinity; false otherwise.
public boolean isNaN()
true if the value represented by this object is
NaN; false otherwise.
public boolean isInfinite()
true if the value represented by this object is
positive infinity or negative infinity;
false otherwise.
public String toString()
double value represented by this
object is converted to a string exactly as if by the method
toString of one argument.
String representation of this object.
public byte byteValue()
public short shortValue()
public int intValue()
double value represented by this object is
converted to type int and the result of the
conversion is returned.
public long longValue()
double value represented by this object is
converted to type long and the result of the
conversion is returned.
public float floatValue()
double value represented by this object is
converted to type float and the result of the
conversion is returned.
public double doubleValue()
double value represented by this object.
public int hashCode()
hash code value for this object.
public boolean equals(Object obj)
true if and only if the argument is
not null and is a Double object that
represents a double that has the identical bit pattern to the bit
pattern of the double represented by this object.
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:
d1 and d2 both represent
Double.NaN, then the equals method
returns true, even though
Double.NaN==Double.NaN has the value
false.
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.
true if the objects are the same;
false otherwise.
public static native long doubleToLongBits(double value)
Bit 63 represents the sign of the floating-point number. Bits 62-52 represent the exponent. Bits 51-0 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.
public static native double longBitsToDouble(long bits)
If the argument is 0x7f80000000000000L, the result
is positive infinity.
If the argument is 0xff80000000000000L, 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 NaN. All IEEE 754
NaN values are, in effect, lumped together by the Java language
into a single value.
long integer.
double floating-point value with the same
bit pattern.
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