Class MutablePatternModifier

java.lang.Object
com.ibm.icu.impl.number.MutablePatternModifier
All Implemented Interfaces:
AffixUtils.SymbolProvider, MicroPropsGenerator, Modifier

public class MutablePatternModifier extends Object implements Modifier, AffixUtils.SymbolProvider, MicroPropsGenerator
This class is a Modifier that wraps a decimal format pattern. It applies the pattern's affixes in Modifier.apply(com.ibm.icu.impl.FormattedStringBuilder, int, int).

In addition to being a Modifier, this class contains the business logic for substituting the correct locale symbols into the affixes of the decimal format pattern.

In order to use this class, create a new instance and call the following four setters: setPatternInfo(com.ibm.icu.impl.number.AffixPatternProvider, com.ibm.icu.text.NumberFormat.Field), setPatternAttributes(com.ibm.icu.number.NumberFormatter.SignDisplay, boolean, boolean), setSymbols(com.ibm.icu.text.DecimalFormatSymbols, com.ibm.icu.util.Currency, com.ibm.icu.number.NumberFormatter.UnitWidth, com.ibm.icu.text.PluralRules), and setNumberProperties(com.ibm.icu.impl.number.Modifier.Signum, com.ibm.icu.impl.StandardPlural). After calling these four setters, the instance will be ready for use as a Modifier.

This is a MUTABLE, NON-THREAD-SAFE class designed for performance. Do NOT save references to this or attempt to use it from multiple threads! Instead, you can obtain a safe, immutable decimal format pattern modifier by calling createImmutable(), in effect treating this instance as a builder for the immutable variant.

  • Field Details

  • Constructor Details

    • MutablePatternModifier

      public MutablePatternModifier(boolean isStrong)
      Parameters:
      isStrong - Whether the modifier should be considered strong. For more information, see Modifier.isStrong(). Most of the time, decimal format pattern modifiers should be considered as non-strong.
  • Method Details

    • setPatternInfo

      public void setPatternInfo(AffixPatternProvider patternInfo, NumberFormat.Field field)
      Sets a reference to the parsed decimal format pattern, usually obtained from PatternStringParser.parseToPatternInfo(String), but any implementation of AffixPatternProvider is accepted.
      Parameters:
      field - Which field to use for literal characters in the pattern.
    • setPatternAttributes

      public void setPatternAttributes(NumberFormatter.SignDisplay signDisplay, boolean perMille, boolean approximately)
      Sets attributes that imply changes to the literal interpretation of the pattern string affixes.
      Parameters:
      signDisplay - Whether to force a plus sign on positive numbers.
      perMille - Whether to substitute the percent sign in the pattern with a permille sign.
      approximately - Whether to prepend approximately to the sign
    • setSymbols

      public void setSymbols(DecimalFormatSymbols symbols, Currency currency, NumberFormatter.UnitWidth unitWidth, PluralRules rules)
      Sets locale-specific details that affect the symbols substituted into the pattern string affixes.
      Parameters:
      symbols - The desired instance of DecimalFormatSymbols.
      currency - The currency to be used when substituting currency values into the affixes.
      unitWidth - The width used to render currencies.
      rules - Required if the triple currency sign, "¤¤¤", appears in the pattern, which can be determined from the convenience method needsPlurals().
    • setNumberProperties

      public void setNumberProperties(Modifier.Signum signum, StandardPlural plural)
      Sets attributes of the current number being processed.
      Parameters:
      signum - -1 if negative; +1 if positive; or 0 if zero.
      plural - The plural form of the number, required only if the pattern contains the triple currency sign, "¤¤¤" (and as indicated by needsPlurals()).
    • needsPlurals

      public boolean needsPlurals()
      Returns true if the pattern represented by this MurkyModifier requires a plural keyword in order to localize. This is currently true only if there is a currency long name placeholder in the pattern ("¤¤¤").
    • createImmutable

      Creates a new quantity-dependent Modifier that behaves the same as the current instance, but which is immutable and can be saved for future use. The number properties in the current instance are mutated; all other properties are left untouched.

      The resulting modifier cannot be used in a QuantityChain.

      Returns:
      An immutable that supports both positive and negative numbers.
    • createConstantModifier

      Uses the current properties to create a single ConstantMultiFieldModifier with currency spacing support if required.
      Parameters:
      a - A working FormattedStringBuilder object; passed from the outside to prevent the need to create many new instances if this method is called in a loop.
      b - Another working FormattedStringBuilder object.
      Returns:
      The constant modifier object.
    • addToChain

      public MicroPropsGenerator addToChain(MicroPropsGenerator parent)
      Used by the unsafe code path.
    • processQuantity

      public MicroProps processQuantity(DecimalQuantity fq)
      Description copied from interface: MicroPropsGenerator
      Considers the given DecimalQuantity, optionally mutates it, and returns a MicroProps.
      Specified by:
      processQuantity in interface MicroPropsGenerator
      Parameters:
      fq - The quantity for consideration and optional mutation.
      Returns:
      A MicroProps instance resolved for the quantity.
    • apply

      public int apply(FormattedStringBuilder output, int leftIndex, int rightIndex)
      Description copied from interface: Modifier
      Apply this Modifier to the string builder.
      Specified by:
      apply in interface Modifier
      Parameters:
      output - The string builder to which to apply this modifier.
      leftIndex - The left index of the string within the builder. Equal to 0 when only one number is being formatted.
      rightIndex - The right index of the string within the string builder. Equal to length when only one number is being formatted.
      Returns:
      The number of characters (UTF-16 code units) that were added to the string builder.
    • getPrefixLength

      public int getPrefixLength()
      Description copied from interface: Modifier
      Gets the length of the prefix. This information can be used in combination with Modifier.apply(com.ibm.icu.impl.FormattedStringBuilder, int, int) to extract the prefix and suffix strings.
      Specified by:
      getPrefixLength in interface Modifier
      Returns:
      The number of characters (UTF-16 code units) in the prefix.
    • getCodePointCount

      public int getCodePointCount()
      Description copied from interface: Modifier
      Returns the number of code points in the modifier, prefix plus suffix.
      Specified by:
      getCodePointCount in interface Modifier
    • isStrong

      public boolean isStrong()
      Description copied from interface: Modifier
      Whether this modifier is strong. If a modifier is strong, it should always be applied immediately and not allowed to bubble up. With regard to padding, strong modifiers are considered to be on the inside of the prefix and suffix.
      Specified by:
      isStrong in interface Modifier
      Returns:
      Whether the modifier is strong.
    • containsField

      public boolean containsField(Format.Field field)
      Description copied from interface: Modifier
      Whether the modifier contains at least one occurrence of the given field.
      Specified by:
      containsField in interface Modifier
    • getParameters

      public Modifier.Parameters getParameters()
      Description copied from interface: Modifier
      Gets a set of "parameters" for this Modifier.
      Specified by:
      getParameters in interface Modifier
    • semanticallyEquivalent

      public boolean semanticallyEquivalent(Modifier other)
      Description copied from interface: Modifier
      Returns whether this Modifier is *semantically equivalent* to the other Modifier; in many cases, this is the same as equal, but parameters should be ignored.
      Specified by:
      semanticallyEquivalent in interface Modifier
    • insertPrefix

      private int insertPrefix(FormattedStringBuilder sb, int position)
    • insertSuffix

      private int insertSuffix(FormattedStringBuilder sb, int position)
    • prepareAffix

      private void prepareAffix(boolean isPrefix)
      Pre-processes the prefix or suffix into the currentAffix field, creating and mutating that field if necessary. Calls down to
      invalid reference
      PatternStringUtils#affixPatternProviderToStringBuilder
      .
      Parameters:
      isPrefix - true to prepare the prefix; false to prepare the suffix.
    • getSymbol

      public CharSequence getSymbol(int type)
      Returns the string that substitutes a given symbol type in a pattern.
      Specified by:
      getSymbol in interface AffixUtils.SymbolProvider
    • getCurrencySymbolForUnitWidth

      public String getCurrencySymbolForUnitWidth()
      Returns the currency symbol for the unit width specified in setSymbols()