Class java.lang.Double 
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Class java.lang.Double 

java.lang.Object
   |
   +----java.lang.Number
           |
           +----java.lang.Double
public final class Double
extends Number
The Double class provides an object wrapper for Double data values and serves as a place for double-oriented operations. A wrapper is useful because most of Java's utility classes require the use of objects. Since doubles are not objects in Java, they need to be "wrapped" in a Double instance.

Variable Index

o MAX_VALUE
The maximum value a double can have.
o MIN_VALUE
The minimum value a double can have.
o NEGATIVE_INFINITY
Negative infinity.
o NaN
Not-a-Number.
o POSITIVE_INFINITY
Positive infinity.

Constructor Index

o Double(double)
Constructs a Double wrapper for the specified double value.
o Double(String)
Constructs a Double object initialized to the value specified by the String parameter.

Method Index

o doubleToLongBits(double)
Returns the bit represention of a double-float value
o doubleValue()
Returns the double value of this Double.
o equals(Object)
Compares this object against the specified object.
o floatValue()
Returns the float value of this Double.
o hashCode()
Returns a hashcode for this Double.
o intValue()
Returns the integer value of this Double (by casting to an int).
o isInfinite(double)
Returns true if the specified number is infinitely large in magnitude.
o isInfinite()
Returns true if this Double value is infinitely large in magnitude.
o isNaN(double)
Returns true if the specified number is the special Not-a-Number (NaN) value.
o isNaN()
Returns true if this Double value is the special Not-a-Number (NaN) value.
o longBitsToDouble(long)
Returns the double-float corresponding to a given bit represention.
o longValue()
Returns the long value of this Double (by casting to a long).
o toString(double)
Returns a String representation for the specified double value.
o toString()
Returns a String representation of this Double object.
o valueOf(String)
Returns a new Double value initialized to the value represented by the specified String.

Variables

o POSITIVE_INFINITY 
  public final static double POSITIVE_INFINITY
Positive infinity.
o NEGATIVE_INFINITY 
  public final static double NEGATIVE_INFINITY
Negative infinity.
o NaN 
  public final static double NaN
Not-a-Number. Note: is not equal to anything, including itself
o MAX_VALUE 
  public final static double MAX_VALUE
The maximum value a double can have. The greatest maximum value that a double can have is 1.79769313486231570e+308d.
o MIN_VALUE 
  public final static double MIN_VALUE
The minimum value a double can have. The lowest minimum value that a double can have is 4.94065645841246544e-324d.

Constructors

o Double 
  public Double(double value)
Constructs a Double wrapper for the specified double value.
Parameters:
value - the initial value of the double
o Double 
  public Double(String s) throws NumberFormatException
Constructs a Double object initialized to the value specified by the String parameter.
Parameters:
s - the String to be converted to a Double
Throws: NumberFormatException
If the String does not contain a parsable number.

Methods

o toString 
  public static String toString(double d)
Returns a String representation for the specified double value.
Parameters:
d - the double to be converted
o valueOf 
  public static Double valueOf(String s) throws NumberFormatException
Returns a new Double value initialized to the value represented by the specified String.
Parameters:
s - the String to be parsed
Throws: NumberFormatException
If the String cannot be parsed.
o isNaN 
  public static boolean isNaN(double v)
Returns true if the specified number is the special Not-a-Number (NaN) value.
Parameters:
v - the value to be tested
o isInfinite 
  public static boolean isInfinite(double v)
Returns true if the specified number is infinitely large in magnitude.
Parameters:
v - the value to be tested
o isNaN 
  public boolean isNaN()
Returns true if this Double value is the special Not-a-Number (NaN) value.
o isInfinite 
  public boolean isInfinite()
Returns true if this Double value is infinitely large in magnitude.
o toString 
  public String toString()
Returns a String representation of this Double object.
Overrides:
toString in class Object
o intValue 
  public int intValue()
Returns the integer value of this Double (by casting to an int).
Overrides:
intValue in class Number
o longValue 
  public long longValue()
Returns the long value of this Double (by casting to a long).
Overrides:
longValue in class Number
o floatValue 
  public float floatValue()
Returns the float value of this Double.
Overrides:
floatValue in class Number
o doubleValue 
  public double doubleValue()
Returns the double value of this Double.
Overrides:
doubleValue in class Number
o hashCode 
  public int hashCode()
Returns a hashcode for this Double.
Overrides:
hashCode in class Object
o equals 
  public boolean equals(Object obj)
Compares this object against the specified object.

Note: To be useful in hashtables this method considers two NaN double values to be equal. This is not according to IEEE specification

Parameters:
obj - the object to compare with
Returns:
true if the objects are the same; false otherwise.
Overrides:
equals in class Object
o doubleToLongBits 
  public static long doubleToLongBits(double value)
Returns the bit represention of a double-float value
o longBitsToDouble 
  public static double longBitsToDouble(long bits)
Returns the double-float corresponding to a given bit represention. 
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