# Package com.fasterxml.jackson.core.io.doubleparser

Provides parsers that parse a `FloatingPointLiteral` from a `CharSequence`, `char` array, or `byte` array (`str`);.

See: Description

Class Summary
FastDoubleParser: Provides static method for parsing a `double` from a `CharSequence`, `char` array or `byte` array.
FastFloatParser: Provides static method for parsing a `float` from a `CharSequence`, `char` array or `byte` array.

## Package com.fasterxml.jackson.core.io.doubleparser Description

Provides parsers that parse a `FloatingPointLiteral` from a `CharSequence`, `char` array, or `byte` array (`str`);.

Leading and trailing whitespace characters in `str` are ignored. Whitespace is removed as if by the `String.trim()` method; that is, characters in the range [U+0000,U+0020].

The rest of `str` should constitute a `FloatingPointLiteral` as described by the lexical syntax rules shown below:

> FloatingPointLiteral:
>   [Sign] `NaN`
>   [Sign] `Infinity`
>   [Sign] DecimalFloatingPointLiteral
>   [Sign] HexFloatingPointLiteral
>   SignedInteger
> HexFloatingPointLiteral:
>   HexSignificand BinaryExponent [FloatTypeSuffix]
> HexSignificand:
>   HexNumeral
>   HexNumeral `.`
>   `0x` [HexDigits] `.` HexDigits
>   `0X` [HexDigits] `.` HexDigits
> BinaryExponent:
>   BinaryExponentIndicator SignedInteger
> BinaryExponentIndicator:
>   `p`
>   `P`
> DecimalFloatingPointLiteral:
>   DecSignificand [DecExponent] [FloatTypeSuffix]
> DecSignificand:
>   Digits `.` [Digits]
>   `.` Digits
>   Digits
> DecExponent:
>   ExponentIndicator SignedInteger
> ExponentIndicator:
>   (one of)
>   e E
> SignedInteger:
>   [Sign] Digits
> Sign:
>   (one of)
>   + -
> Digits:
>   Digit {Digit}
> HexNumeral:
>   `0` `x` HexDigits
>   `0` `X` HexDigits
> HexDigits:
>   HexDigit {HexDigit}
> HexDigit:
>   (one of)
>   `0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F`
> FloatTypeSuffix:
>   (one of)
>   `f F d D`

References:

The Java® Language Specification, Java SE 18 Edition, Chapter 3. Lexical Structure, 3.10.2. Floating-Point Literals
  docs.oracle.com