Top Description Fields Constructors Methods
java.lang

public abstract Class Number

extends Object
implements Serializable
Class Inheritance
All Implemented Interfaces
java.io.Serializable
Known Direct Subclasses
java.lang.Short, java.math.BigDecimal, java.math.BigInteger, java.util.concurrent.atomic.AtomicInteger, java.util.concurrent.atomic.AtomicLong, java.util.concurrent.atomic.Striped64, java.lang.Byte, java.lang.Double, java.lang.Float, java.lang.Integer, java.lang.Long

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 defined 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.
Authors
Lee Boynton, Arthur van Hoff
Since
1.0
Java Language Specification
5.1.2 Widening Primitive Conversion, 5.1.3 Narrowing Primitive Conversion

Field Summary

Modifier and TypeField and Description
private static final long
serialVersionUID

use serialVersionUID from JDK 1.0.2 for interoperability

Constructor Summary

AccessConstructor and Description
public
Number()

Constructor for subclasses to call.

Method Summary

Modifier and TypeMethod and Description
public byte

Returns:

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

Returns the value of the specified number as a byte.

public abstract double

Returns:

the numeric value represented by this object after conversion to type double.
doubleValue
()

Returns the value of the specified number as a double.

public abstract float

Returns:

the numeric value represented by this object after conversion to type float.
floatValue
()

Returns the value of the specified number as a float.

public abstract int

Returns:

the numeric value represented by this object after conversion to type int.
intValue
()

Returns the value of the specified number as an int.

public abstract long

Returns:

the numeric value represented by this object after conversion to type long.
longValue
()

Returns the value of the specified number as a long.

public short

Returns:

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

Returns the value of the specified number as a short.

Inherited from java.lang.Object:
cloneequalsfinalizegetClasshashCodenotifynotifyAlltoStringwaitwaitwait

Field Detail

serialVersionUIDback to summary
private static final long serialVersionUID

use serialVersionUID from JDK 1.0.2 for interoperability

Annotations
@Serial

Constructor Detail

Numberback to summary
public Number()

Constructor for subclasses to call.

Method Detail

byteValueback to summary
public byte byteValue()

Returns the value of the specified number as a byte.

Implementation Specification

The default implementation returns the result of intValue cast to a byte.

Returns:byte

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

Since
1.1
doubleValueback to summary
public abstract double doubleValue()

Returns the value of the specified number as a double.

Returns:double

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

floatValueback to summary
public abstract float floatValue()

Returns the value of the specified number as a float.

Returns:float

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

intValueback to summary
public abstract int intValue()

Returns the value of the specified number as an int.

Returns:int

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

longValueback to summary
public abstract long longValue()

Returns the value of the specified number as a long.

Returns:long

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

shortValueback to summary
public short shortValue()

Returns the value of the specified number as a short.

Implementation Specification

The default implementation returns the result of intValue cast to a short.

Returns:short

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

Since
1.1