java.lang

Class Number

java.lang.Object

java.lang.Number

Direct Known Subclasses:

Byte, Double, Float, Integer, Long, Short

public abstract class Number
extends Object

The abstract class Number is the superclass of Byte, Double, Float, Integer, Long, and Short. Subclasses of Number must provide methods to convert the represented numeric value to 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, CLDC1.8

See Also:

Byte, Double, Float, Integer, Long, Short

See The Java™ Language Specification:

5.1.2 Widening Primitive Conversions, 5.1.3 Narrowing Primitive Conversions

Constructor Summary

Constructors

Constructor and Description
Number()

Method Summary

Methods

Modifier and Type	Method and 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

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Number

public Number()

Method Detail

byteValue

public byte byteValue()

Returns the value of the specified number as a byte, which may involve rounding or truncation.

Returns:

the numeric value represented by this object after conversion to type byte.

Since:

JDK1.1

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.

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.

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.

shortValue

public short shortValue()

Returns the value of the specified number as a short, which may involve rounding or truncation.

Returns:

the numeric value represented by this object after conversion to type short.

Since:

JDK1.1