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Number (Java SE 26 & JDK 26)

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java.lang.Object

java.lang.Number

All Implemented Interfaces: Serializable Direct Known Subclasses: AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, Double, DoubleAccumulator, DoubleAdder, Float, Float16, 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 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.

See Java Language Specification: 5.1.2 Widening Primitive Conversion
5.1.3 Narrowing Primitive Conversion
Since: 1.0 See Also:

Constructor Summary

Constructors

Constructor

Description

Number()

Constructor for subclasses to call.
Method Summary

All MethodsInstance MethodsAbstract MethodsConcrete Methods

Modifier and Type

Method

Description

byte

byteValue()

Returns the value of the specified number as a byte.

abstract double

doubleValue()

Returns the value of the specified number as a double.

abstract float

floatValue()

Returns the value of the specified number as a float.

abstract int

intValue()

Returns the value of the specified number as an int.

abstract long

longValue()

Returns the value of the specified number as a long.

short

shortValue()

Returns the value of the specified number as a short.

Methods declared in class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Modifier and Type

Method

Description

protected Object

clone()

Creates and returns a copy of this object.

boolean

equals(Object obj)

Indicates whether some other object is "equal to" this one.

protected void

finalize()

Deprecated, for removal: This API element is subject to removal in a future version.
Finalization is deprecated and subject to removal in a future release.

final Class<?>

getClass()

Returns the runtime class of this Object.

int

hashCode()

Returns a hash code value for this object.

final void

notify()

Wakes up a single thread that is waiting on this object's monitor.

final void

notifyAll()

Wakes up all threads that are waiting on this object's monitor.

String

toString()

Returns a string representation of the object.

final void

wait()

Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

final void

wait(long timeoutMillis)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void

wait(long timeoutMillis, int nanos)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details
- Number
  
  public Number()
  
  Constructor for subclasses to call.
Method Details
- intValue
  
  public abstract int intValue()
  
  Returns the value of the specified number as an int.
  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.
  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.
  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.
  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.
  Implementation Requirements: The default implementation returns the result of intValue() cast to a byte. Returns: the numeric value represented by this object after conversion to type byte. Since: 1.1
- shortValue
  
  public short shortValue()
  
  Returns the value of the specified number as a short.
  Implementation Requirements: The default implementation returns the result of intValue() cast to a short. Returns: the numeric value represented by this object after conversion to type short. Since: 1.1

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Class Number

Constructor Summary

Method Summary

Methods declared in class Object

Constructor Details

Number

Method Details

intValue

longValue

floatValue

doubleValue

byteValue

shortValue