Class Precision

java.lang.Object
com.ibm.icu.number.Precision
Direct Known Subclasses:
CurrencyPrecision, FractionPrecision, Precision.BogusRounder

public abstract class Precision extends Object
A class that defines the rounding precision to be used when formatting numbers in NumberFormatter.

To create a Precision, use one of the factory methods.

See Also:
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static class 
    Deprecated.
    This API is ICU internal only.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    Deprecated.
    ICU internal only.
  • Method Summary

    Modifier and Type
    Method
    Description
    abstract void
    apply(com.ibm.icu.impl.number.DecimalQuantity value)
    Deprecated.
    ICU 60 This API is ICU internal only.
    Show numbers rounded and padded according to the rules for the currency unit.
    fixedFraction(int minMaxFractionPlaces)
    Show numbers rounded if necessary to a certain number of fraction places (numerals after the decimal separator).
    static Precision
    fixedSignificantDigits(int minMaxSignificantDigits)
    Show numbers rounded if necessary to a certain number of significant digits or significant figures.
    static Precision
    increment(BigDecimal roundingIncrement)
    Show numbers rounded if necessary to the closest multiple of a certain rounding increment.
    Show numbers rounded if necessary to the nearest integer.
    maxFraction(int maxFractionPlaces)
    Show numbers rounded if necessary to a certain number of fraction places (numerals after the decimal separator).
    static Precision
    maxSignificantDigits(int maxSignificantDigits)
    Show numbers rounded if necessary to a certain number of significant digits/figures.
    minFraction(int minFractionPlaces)
    Always show at least a certain number of fraction places after the decimal separator, padding with zeros if necessary.
    minMaxFraction(int minFractionPlaces, int maxFractionPlaces)
    Show numbers rounded if necessary to a certain number of fraction places (numerals after the decimal separator); in addition, always show at least a certain number of places after the decimal separator, padding with zeros if necessary.
    static Precision
    minMaxSignificantDigits(int minSignificantDigits, int maxSignificantDigits)
    Show numbers rounded if necessary to a certain number of significant digits/figures; in addition, always show at least a certain number of significant digits, padding with zeros if necessary.
    static Precision
    minSignificantDigits(int minSignificantDigits)
    Always show at least a certain number of significant digits/figures, padding with zeros if necessary.
    Configure how trailing zeros are displayed on numbers.
    static Precision
    Show all available digits to full precision.
    withMode(MathContext mathContext)
    Deprecated.
    This API is ICU internal only.

    Methods inherited from class java.lang.Object

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

  • Method Details

    • unlimited

      public static Precision unlimited()
      Show all available digits to full precision.

      NOTE: When formatting a double, this method, along with minFraction(int) and minSignificantDigits(int), will trigger complex algorithm similar to Dragon4 to determine the low-order digits and the number of digits to display based on the value of the double. If the number of fraction places or significant digits can be bounded, consider using maxFraction(int) or maxSignificantDigits(int) instead to maximize performance. For more information, read the following blog post.

      http://www.serpentine.com/blog/2011/06/29/here-be-dragons-advances-in-problems-you-didnt-even-know-you-had/

      Returns:
      A Precision for chaining or passing to the NumberFormatter precision() setter.
      See Also:
    • integer

      public static FractionPrecision integer()
      Show numbers rounded if necessary to the nearest integer.
      Returns:
      A FractionPrecision for chaining or passing to the NumberFormatter precision() setter.
      See Also:
    • fixedFraction

      public static FractionPrecision fixedFraction(int minMaxFractionPlaces)
      Show numbers rounded if necessary to a certain number of fraction places (numerals after the decimal separator). Additionally, pad with zeros to ensure that this number of places are always shown.

      Example output with minMaxFractionPlaces = 3:

      87,650.000
      8,765.000
      876.500
      87.650
      8.765
      0.876
      0.088
      0.009
      0.000 (zero)

      This method is equivalent to minMaxFraction(int, int) with both arguments equal.

      Parameters:
      minMaxFractionPlaces - The minimum and maximum number of numerals to display after the decimal separator (rounding if too long or padding with zeros if too short).
      Returns:
      A FractionPrecision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 0.
      See Also:
    • minFraction

      public static FractionPrecision minFraction(int minFractionPlaces)
      Always show at least a certain number of fraction places after the decimal separator, padding with zeros if necessary. Do not perform rounding (display numbers to their full precision).

      NOTE: If you are formatting doubles, see the performance note in unlimited().

      Parameters:
      minFractionPlaces - The minimum number of numerals to display after the decimal separator (padding with zeros if necessary).
      Returns:
      A FractionPrecision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 0.
      See Also:
    • maxFraction

      public static FractionPrecision maxFraction(int maxFractionPlaces)
      Show numbers rounded if necessary to a certain number of fraction places (numerals after the decimal separator). Unlike the other fraction rounding strategies, this strategy does not pad zeros to the end of the number.
      Parameters:
      maxFractionPlaces - The maximum number of numerals to display after the decimal mark (rounding if necessary).
      Returns:
      A FractionPrecision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 0.
      See Also:
    • minMaxFraction

      public static FractionPrecision minMaxFraction(int minFractionPlaces, int maxFractionPlaces)
      Show numbers rounded if necessary to a certain number of fraction places (numerals after the decimal separator); in addition, always show at least a certain number of places after the decimal separator, padding with zeros if necessary.
      Parameters:
      minFractionPlaces - The minimum number of numerals to display after the decimal separator (padding with zeros if necessary).
      maxFractionPlaces - The maximum number of numerals to display after the decimal separator (rounding if necessary).
      Returns:
      A FractionPrecision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 0.
      See Also:
    • fixedSignificantDigits

      public static Precision fixedSignificantDigits(int minMaxSignificantDigits)
      Show numbers rounded if necessary to a certain number of significant digits or significant figures. Additionally, pad with zeros to ensure that this number of significant digits/figures are always shown.

      This method is equivalent to minMaxSignificantDigits(int, int) with both arguments equal.

      Parameters:
      minMaxSignificantDigits - The minimum and maximum number of significant digits to display (rounding if too long or padding with zeros if too short).
      Returns:
      A Precision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 1.
      See Also:
    • minSignificantDigits

      public static Precision minSignificantDigits(int minSignificantDigits)
      Always show at least a certain number of significant digits/figures, padding with zeros if necessary. Do not perform rounding (display numbers to their full precision).

      NOTE: If you are formatting doubles, see the performance note in unlimited().

      Parameters:
      minSignificantDigits - The minimum number of significant digits to display (padding with zeros if too short).
      Returns:
      A Precision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 1.
      See Also:
    • maxSignificantDigits

      public static Precision maxSignificantDigits(int maxSignificantDigits)
      Show numbers rounded if necessary to a certain number of significant digits/figures.
      Parameters:
      maxSignificantDigits - The maximum number of significant digits to display (rounding if too long).
      Returns:
      A Precision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 1.
      See Also:
    • minMaxSignificantDigits

      public static Precision minMaxSignificantDigits(int minSignificantDigits, int maxSignificantDigits)
      Show numbers rounded if necessary to a certain number of significant digits/figures; in addition, always show at least a certain number of significant digits, padding with zeros if necessary.
      Parameters:
      minSignificantDigits - The minimum number of significant digits to display (padding with zeros if necessary).
      maxSignificantDigits - The maximum number of significant digits to display (rounding if necessary).
      Returns:
      A Precision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the input number is too big or smaller than 1.
      See Also:
    • increment

      public static Precision increment(BigDecimal roundingIncrement)
      Show numbers rounded if necessary to the closest multiple of a certain rounding increment. For example, if the rounding increment is 0.5, then round 1.2 to 1 and round 1.3 to 1.5.

      In order to ensure that numbers are padded to the appropriate number of fraction places, set the scale on the rounding increment BigDecimal. For example, to round to the nearest 0.5 and always display 2 numerals after the decimal separator (to display 1.2 as "1.00" and 1.3 as "1.50"), you can run:

       Precision.increment(new BigDecimal("0.50"))
       

      For more information on the scale of Java BigDecimal, see BigDecimal.scale().

      Parameters:
      roundingIncrement - The increment to which to round numbers.
      Returns:
      A Precision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if the rounding increment is null or non-positive.
      See Also:
    • currency

      public static CurrencyPrecision currency(Currency.CurrencyUsage currencyUsage)
      Show numbers rounded and padded according to the rules for the currency unit. The most common rounding precision settings for currencies include Precision.fixedFraction(2), Precision.integer(), and Precision.increment(0.05) for cash transactions ("nickel rounding").

      The exact rounding details will be resolved at runtime based on the currency unit specified in the NumberFormatter chain. To round according to the rules for one currency while displaying the symbol for another currency, the withCurrency() method can be called on the return value of this method.

      Parameters:
      currencyUsage - Either STANDARD (for digital transactions) or CASH (for transactions where the rounding increment may be limited by the available denominations of cash or coins).
      Returns:
      A CurrencyPrecision for chaining or passing to the NumberFormatter precision() setter.
      Throws:
      IllegalArgumentException - if currencyUsage is null.
      See Also:
    • trailingZeroDisplay

      public Precision trailingZeroDisplay(NumberFormatter.TrailingZeroDisplay trailingZeroDisplay)
      Configure how trailing zeros are displayed on numbers. For example, to hide trailing zeros when the number is an integer, use HIDE_IF_WHOLE.
      Parameters:
      trailingZeroDisplay - Option to configure the display of trailing zeros.
    • withMode

      @Deprecated public Precision withMode(MathContext mathContext)
      Deprecated.
      This API is ICU internal only.
      Sets a MathContext to use on this Precision.
    • apply

      @Deprecated public abstract void apply(com.ibm.icu.impl.number.DecimalQuantity value)
      Deprecated.
      ICU 60 This API is ICU internal only.