# Class Double

java.lang.Object
java.lang.Number
java.lang.Double

All Implemented Interfaces:
  `Comparable<Double>`

public final class Double extends Number implements Comparable<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. Since: JDK1.0, CLDC 1.1

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final double`
  `MAX_VALUE`
  The largest positive finite value of type double.
  `static final double`
  `MIN_VALUE`
  The smallest positive value of type double.
  `static final double`
  `NaN`
  A Not-a-Number (NaN) value of type double.
  `static final double`
  `NEGATIVE_INFINITY`
  The negative infinity of type double.
  `static final double`
  `POSITIVE_INFINITY`
  The positive infinity of type double.
  `static final Class<Double>`
  `TYPE`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Double(double value)`
  Constructs a newly allocated Double object that represents the primitive double argument.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `byte`
  `byteValue()`
  Returns the value of this Double as a byte (by casting to a byte).
  `static int`
  `compare(double d1, double d2)`
  `int`
  `compareTo(Double d)`
  Compares this object to the specified object to determine their relative order.
  `static long`
  `doubleToLongBits(double value)`
  Returns a representation of the specified floating-point value according to the IEEE 754 floating-point "double format" bit layout.
  `double`
  `doubleValue()`
  Returns the double value of this Double.
  `boolean`
  `equals(Object obj)`
  Compares this object against the specified object.
  `float`
  `floatValue()`
  Returns the float value of this Double.
  `int`
  `hashCode()`
  Returns a hashcode for this Double object.
  `int`
  `intValue()`
  Returns the integer value of this Double (by casting to an int).
  `boolean`
  `isInfinite()`
  Returns true if this Double value is infinitely large in magnitude.
  `static boolean`
  `isInfinite(double v)`
  Returns true if the specified number is infinitely large in magnitude.
  `boolean`
  `isNaN()`
  Returns true if this Double value is the special Not-a-Number (NaN) value.
  `static boolean`
  `isNaN(double v)`
  Returns true if the specified number is the special Not-a-Number (NaN) value.
  `static double`
  `longBitsToDouble(long bits)`
  Returns the double-float corresponding to a given bit representation.
  `long`
  `longValue()`
  Returns the long value of this Double (by casting to a long).
  `static double`
  `parseDouble(String s)`
  Returns a new double initialized to the value represented by the specified String, as performed by the valueOf method of class Double.
  `short`
  `shortValue()`
  Returns the value of this Double as a short (by casting to a short).
  `String`
  `toString()`
  Returns a String representation of this Double object.
  `static String`
  `toString(double d)`
  Creates a string representation of the double argument.
  `static Double`
  `valueOf(double i)`
  Returns the object instance of i
  `static Double`
  `valueOf(String s)`
  Returns a new Double object initialized to the value represented by the specified string.

  ### Methods inherited from class Object

  `clone, getClass, notify, notifyAll, wait, wait, wait`

- ## Field Details

  - ### TYPE

    public static final Class<Double> TYPE

  - ### MAX_VALUE

    public static final double MAX_VALUE
    The largest positive finite value of type double. It is equal to the value returned by Double.longBitsToDouble(0x7fefffffffffffffL) See Also:Constant Field Values
    See Also:
      - Constant Field Values

  - ### MIN_VALUE

    public static final double MIN_VALUE
    The smallest positive value of type double. It is equal to the value returned by Double.longBitsToDouble(0x1L).
    See Also:
      - Constant Field Values

  - ### NaN

    public static final double NaN
    A Not-a-Number (NaN) value of type double. It is equal to the value returned by Double.longBitsToDouble(0x7ff8000000000000L). See Also:Constant Field Values
    See Also:
      - Constant Field Values

  - ### NEGATIVE_INFINITY

    public static final double NEGATIVE_INFINITY
    The negative infinity of type double. It is equal to the value returned by Double.longBitsToDouble(0xfff0000000000000L). See Also:Constant Field Values
    See Also:
      - Constant Field Values

  - ### POSITIVE_INFINITY

    public static final double POSITIVE_INFINITY
    The positive infinity of type double. It is equal to the value returned by Double.longBitsToDouble(0x7ff0000000000000L). See Also:Constant Field Values
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Double

    public Double(double value)
    Constructs a newly allocated Double object that represents the primitive double argument. value - the value to be represented by the Double.

- ## Method Details

  - ### byteValue

    public byte byteValue()
    Returns the value of this Double as a byte (by casting to a byte).
    Overrides:
      `byteValue` in class `Number`

  - ### doubleToLongBits

    public static long doubleToLongBits(double 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 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 longBitsToDouble(long) method, will produce a floating-point value equal to the argument to doubleToLongBits.

  - ### doubleValue

    public double doubleValue()
    Returns the double value of this Double.
    Specified by:
      `doubleValue` in class `Number`

  - ### equals

    public boolean equals(Object obj)
    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 identical bit pattern to the bit pattern of the double represented by this object. For this purpose, two double values are considered to be the same if and only if the method returns the same 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 equals test has the value false, even though +0.0==-0.0 has the value true. This allows hashtables to operate properly.
    Overrides:
      `equals` in class `Object`

  - ### floatValue

    public float floatValue()
    Returns the float value of this Double.
    Specified by:
      `floatValue` in class `Number`

  - ### hashCode

    public int hashCode()
    Returns a hashcode 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 , of the primitive double value represented by this Double object. That is, the hashcode is the value of the expression: (int)(v^(v>>>32)) where v is defined by: long v = Double.doubleToLongBits(this.doubleValue());
    Overrides:
      `hashCode` in class `Object`

  - ### intValue

    public int intValue()
    Returns the integer value of this Double (by casting to an int).
    Specified by:
      `intValue` in class `Number`

  - ### isInfinite

    public boolean isInfinite()
    Returns true if this Double value is infinitely large in magnitude.

  - ### isInfinite

    public static boolean isInfinite(double v)
    Returns true if the specified number is infinitely large in magnitude.

  - ### isNaN

    public boolean isNaN()
    Returns true if this Double value is the special Not-a-Number (NaN) value.

  - ### isNaN

    public static boolean isNaN(double v)
    Returns true if the specified number is the special Not-a-Number (NaN) value.

  - ### longBitsToDouble

    public static double longBitsToDouble(long bits)
    Returns the double-float 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 precision" bit layout. That floating-point value is returned as the result. 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 NaN. All IEEE 754 NaN values of type double are, in effect, lumped together by the Java programming language into a single value called NaN. 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) invalid input: '<'invalid input: '<' 1 : (bits & 0xfffffffffffffL) | 0x10000000000000L; Then the floating-point result equals the value of the mathematical expression 2e-1075.

  - ### longValue

    public long longValue()
    Returns the long value of this Double (by casting to a long).
    Specified by:
      `longValue` in class `Number`

  - ### parseDouble

    public static double parseDouble(String s) throws NumberFormatException
    Returns a new double initialized to the value represented by the specified String, as performed by the valueOf method of class Double.
    Throws:
      `NumberFormatException`

  - ### shortValue

    public short shortValue()
    Returns the value of this Double as a short (by casting to a short).
    Overrides:
      `shortValue` in class `Number`

  - ### toString

    public String toString()
    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.
    Overrides:
      `toString` in class `Object`

  - ### toString

    public static String toString(double d)
    Creates 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 '-' ('-'); if the sign is positive, no sign character appears in the result. As for the magnitude : If is infinity, it is represented by the characters "Infinity"; thus, positive infinity produces the result "Infinity" and negative infinity produces the result "-Infinity". If 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 is greater than or equal to 10-3 but less than 107, then it is represented as the integer part of , in decimal form with no leading zeroes, followed by '.' (.), followed by one or more decimal digits representing the fractional part of . If is less than 10-3 or not less than 107, then it is represented in so-called "computerized scientific notation." Let be the unique integer such that 10n = 10n+1; then let be the mathematically exact quotient of and 10n so that 1 = 10. The magnitude is then represented as the integer part of , as a single decimal digit, followed by '.' (.), followed by decimal digits representing the fractional part of , followed by the letter 'E' (E), followed by a representation of as a decimal integer, as produced by the method . 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.

  - ### valueOf

    public static Double valueOf(String s) throws NumberFormatException
    Returns a new Double object initialized to the value represented by the specified string. The string s is interpreted as the representation of a floating-point value and a Double object representing that value is created and returned. 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: where and are as defined in Section 3.10.2 of the . If it does not have the form of a , then a NumberFormatException is thrown. Otherwise, it 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. Finally, a new object of class Double is created to represent the double value.
    Throws:
      `NumberFormatException`

  - ### valueOf

    public static Double valueOf(double i)
    Returns the object instance of i
    Parameters:
      `i` - the primitive
    Returns:
      object instance

  - ### compare

    public static int compare(double d1, double d2)

  - ### compareTo

    public int compareTo(Double d)
    Description copied from interface: `Comparable`
    Compares this object to the specified object to determine their relative order.
    Specified by:
      `compareTo` in interface `Comparable<Double>`
    Parameters:
      `d` - the object to compare to this instance.
    Returns:
      a negative integer if this instance is less than `another`; a positive integer if this instance is greater than `another`; 0 if this instance has the same order as `another`.