Module java.base
Package java.lang

Class Number

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 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:
Serialized Form
  • Constructor Summary

    Constructors
    Constructor
    Description
    Constructor for subclasses to call.
  • Method Summary

    Modifier and Type
    Method
    Description
    byte
    Returns the value of the specified number as a byte.
    abstract double
    Returns the value of the specified number as a double.
    abstract float
    Returns the value of the specified number as a float.
    abstract int
    Returns the value of the specified number as an int.
    abstract long
    Returns the value of the specified number as a long.
    short
    Returns the value of the specified number as a short.

    Methods declared in class java.lang.Object

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