com.ibm.icu.number

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:

NumberFormatter

Status:

Stable ICU 62.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Precision.BogusRounder Deprecated. This API is ICU internal only.

Field Summary

Fields

Modifier and Type	Field and Description
static Precision.BogusRounder	BOGUS_PRECISION Deprecated. ICU internal only.

Method Summary

Modifier and Type	Method and Description
abstract void	apply(com.ibm.icu.impl.number.DecimalQuantity value) Deprecated. ICU 60 This API is ICU internal only.
static CurrencyPrecision	currency(Currency.CurrencyUsage currencyUsage) Show numbers rounded and padded according to the rules for the currency unit.
static FractionPrecision	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.
static FractionPrecision	integer() Show numbers rounded if necessary to the nearest integer.
static FractionPrecision	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.
static FractionPrecision	minFraction(int minFractionPlaces) Always show at least a certain number of fraction places after the decimal separator, padding with zeros if necessary.
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.
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.
Precision	trailingZeroDisplay(NumberFormatter.TrailingZeroDisplay trailingZeroDisplay) Configure how trailing zeros are displayed on numbers.
static Precision	unlimited() Show all available digits to full precision.
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 Detail

BOGUS_PRECISION

@Deprecated
public static final Precision.BogusRounder BOGUS_PRECISION

Deprecated. ICU internal only.

Status:

Internal. This API is ICU internal only.

Method Detail

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 62.

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:

NumberFormatter

Status:

Stable ICU 62.

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:

NumberFormatter

Status:

Stable ICU 62.

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:

NumberFormatter

Status:

Stable ICU 62.

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:

NumberFormatter

Status:

Stable ICU 60.

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:

NumberFormatter

Status:

Stable ICU 60.

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.

Status:

Stable ICU 69.

withMode

@Deprecated
public Precision withMode(MathContext mathContext)

Deprecated. This API is ICU internal only.

Sets a MathContext to use on this Precision.

Status:

Internal. This API is ICU internal only.

apply

@Deprecated
public abstract void apply(com.ibm.icu.impl.number.DecimalQuantity value)

Deprecated. ICU 60 This API is ICU internal only.

Status:

Internal. This API is ICU internal only.