The abstract class Number. defines a sup class that is implemented by the classes that wrap the numeric types byte, short, int, long, bloat, and double. Number has abstract methods that return the value of the object in each of the different number formats. That is, double Value() returns the value as a double, float Value() returns the value ~s a float, and so on. These methods are shown here: byte byte Value( )
- double double Value()
- float float Value()
- int int Value( )
- long long Value( )
- short short Value( )
The values returned by these methods can be prowled. ‘ Number has six concrete sub classes that hold “silkily values of each numeric type: Double, Float, Byte, Short, Integer, and Long.
Double and Float
Double and Float are wrappers for floating-point values of type double and float, respectively. The constructors for Float are shown here: .
- Float(double num)
- Float(float num)
- Float(String ) throws Number conceptualization
As you can see, Float objects can be constructed ‘with values of type float or double. They can-also be constructed from the string representation of a Nightlong-point number. The constructors for Double arc shown here: Doublet double ) Double String sir) throws Number Format Exception Double objects can be constructed with a double value or a string containing a floating-point value The methods defined by Flot are shown in Table 14-1. Netherlands defined by Double are shown in,Table 14-2. Both Float and Double define the following constants:
The following example creates two Double objects-one by using a double value and the other by passing a string that can be parsed as a double:As you can see from the following output, both constructors created identical Double instances, as shown by the equals( ),method returning true: 3.14159 = 3.14159 -> true