Number (Java Platform SE 8 ) (original) (raw)

• java.lang.Object

• • java.lang.Number

• All Implemented Interfaces:
  Serializable
  Direct Known Subclasses:
  AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, Double, DoubleAccumulator, DoubleAdder, Float, Integer, Long, LongAccumulator, LongAdder, Short

public abstract class Number
extends Object
implements Serializable
The abstract class Number is the superclass of platform classes representing numeric values that are convertible to the primitive types byte, double, float, int, long, and short. The specific semantics of the conversion from the numeric value of a particular Number implementation to a given primitive type is defined by the Number implementation in question. For platform classes, the conversion is often analogous to a narrowing primitive conversion or a widening primitive conversion as defining in The Java™ Language Specification for converting between primitive types. Therefore, conversions may lose information about the overall magnitude of a numeric value, may lose precision, and may even return a result of a different sign than the input. See the documentation of a given Number implementation for conversion details.
Since:
JDK1.0
See Also:
Serialized Form
See The Java™ Language Specification:
5.1.2 Widening Primitive Conversions, 5.1.3 Narrowing Primitive Conversions

• • Constructor Summary

  Constructors

  Constructor	Description
  Number()

  • Method Summary

  All Methods Instance Methods Abstract Methods Concrete Methods

  Modifier and Type	Method	Description
  byte	byteValue()	Returns the value of the specified number as a byte, which may involve rounding or truncation.
  abstract double	doubleValue()	Returns the value of the specified number as a double, which may involve rounding.
  abstract float	floatValue()	Returns the value of the specified number as a float, which may involve rounding.
  abstract int	intValue()	Returns the value of the specified number as an int, which may involve rounding or truncation.
  abstract long	longValue()	Returns the value of the specified number as a long, which may involve rounding or truncation.
  short	shortValue()	Returns the value of the specified number as a short, which may involve rounding or truncation.

     * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
     `[clone](../../java/lang/Object.html#clone--), [equals](../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../java/lang/Object.html#finalize--), [getClass](../../java/lang/Object.html#getClass--), [hashCode](../../java/lang/Object.html#hashCode--), [notify](../../java/lang/Object.html#notify--), [notifyAll](../../java/lang/Object.html#notifyAll--), [toString](../../java/lang/Object.html#toString--), [wait](../../java/lang/Object.html#wait--), [wait](../../java/lang/Object.html#wait-long-), [wait](../../java/lang/Object.html#wait-long-int-)`

• • Constructor Detail

     * #### Number  
     public Number()  

  • Method Detail

    * #### intValue  
    public abstract int intValue()  
    Returns the value of the specified number as an `int`, which may involve rounding or truncation.  
    Returns:  
    the numeric value represented by this object after conversion to type `int`.  
    * #### longValue  
    public abstract long longValue()  
    Returns the value of the specified number as a `long`, which may involve rounding or truncation.  
    Returns:  
    the numeric value represented by this object after conversion to type `long`.  
    * #### floatValue  
    public abstract float floatValue()  
    Returns the value of the specified number as a `float`, which may involve rounding.  
    Returns:  
    the numeric value represented by this object after conversion to type `float`.  
    * #### doubleValue  
    public abstract double doubleValue()  
    Returns the value of the specified number as a `double`, which may involve rounding.  
    Returns:  
    the numeric value represented by this object after conversion to type `double`.  
    * #### byteValue  
    public byte byteValue()  
    Returns the value of the specified number as a `byte`, which may involve rounding or truncation.  
    This implementation returns the result of [intValue()](../../java/lang/Number.html#intValue--) cast to a `byte`.  
    Returns:  
    the numeric value represented by this object after conversion to type `byte`.  
    Since:  
    JDK1.1  
    * #### shortValue  
    public short shortValue()  
    Returns the value of the specified number as a `short`, which may involve rounding or truncation.  
    This implementation returns the result of [intValue()](../../java/lang/Number.html#intValue--) cast to a `short`.  
    Returns:  
    the numeric value represented by this object after conversion to type `short`.  
    Since:  
    JDK1.1

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