Currency (Java SE 21 & JDK 21)
Description: declaration: module: java.base, package: java.util, class: Currency
Keywords: java.util.Currency class

Module java.base
Package java.util

# Class Currency

java.lang.Object
java.util.Currency

All Implemented Interfaces:
  `Serializable`

public final class Currency extends Object implements Serializable
Represents a currency. Currencies are identified by their ISO 4217 currency codes. Visit the ISO web site for more information.

The class is designed so that there's never more than one `Currency` instance for any given currency. Therefore, there's no public constructor. You obtain a `Currency` instance using the `getInstance` methods.

Users can supersede the Java runtime currency data by means of the system property `java.util.currency.data`. If this system property is defined then its value is the location of a properties file, the contents of which are key/value pairs of the ISO 3166 country codes and the ISO 4217 currency data respectively. The value part consists of three ISO 4217 values of a currency, i.e., an alphabetic code, a numeric code, and a minor unit. Those three ISO 4217 values are separated by commas. The lines which start with '#'s are considered comment lines. An optional UTC timestamp may be specified per currency entry if users need to specify a cutover date indicating when the new data comes into effect. The timestamp is appended to the end of the currency properties and uses a comma as a separator. If a UTC datestamp is present and valid, the JRE will only use the new currency properties if the current UTC date is later than the date specified at class loading time. The format of the timestamp must be of ISO 8601 format : `'yyyy-MM-dd'T'HH:mm:ss'`. For example,

`#Sample currency properties
JP=JPZ,999,0`

will supersede the currency data for Japan. If JPZ is one of the existing ISO 4217 currency code referred by other countries, the existing JPZ currency data is updated with the given numeric code and minor unit value.

`#Sample currency properties with cutover date
JP=JPZ,999,0,2014-01-01T00:00:00`

will supersede the currency data for Japan if `Currency` class is loaded after 1st January 2014 00:00:00 GMT.

Where syntactically malformed entries are encountered, the entry is ignored and the remainder of entries in file are processed. For instances where duplicate country code entries exist, the behavior of the Currency information for that `Currency` is undefined and the remainder of entries in file are processed.

If multiple property entries with same currency code but different numeric code and/or minor unit are encountered, those entries are ignored and the remainder of entries in file are processed.

It is recommended to use `BigDecimal` class while dealing with `Currency` or monetary values as it provides better handling of floating point numbers and their operations.

Since:
  1.4
External Specifications
  - ISO - ISO 4217 - Currency codes
See Also:
  - `BigDecimal`
  - Serialized Form

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static Set<Currency>`
  `getAvailableCurrencies()`
  Gets the set of available currencies.
  `String`
  `getCurrencyCode()`
  Gets the ISO 4217 currency code of this currency.
  `int`
  `getDefaultFractionDigits()`
  Gets the default number of fraction digits used with this currency.
  `String`
  `getDisplayName()`
  Gets the name that is suitable for displaying this currency for the default `DISPLAY` locale.
  `String`
  `getDisplayName(Locale locale)`
  Gets the name that is suitable for displaying this currency for the specified locale.
  `static Currency`
  `getInstance(String currencyCode)`
  Returns the `Currency` instance for the given currency code.
  `static Currency`
  `getInstance(Locale locale)`
  Returns the `Currency` instance for the country of the given locale.
  `int`
  `getNumericCode()`
  Returns the ISO 4217 numeric code of this currency.
  `String`
  `getNumericCodeAsString()`
  Returns the 3 digit ISO 4217 numeric code of this currency as a `String`.
  `String`
  `getSymbol()`
  Gets the symbol of this currency for the default `DISPLAY` locale.
  `String`
  `getSymbol(Locale locale)`
  Gets the symbol of this currency for the specified locale.
  `String`
  `toString()`
  Returns the ISO 4217 currency code of this currency.

  ### Methods declared in class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- ## Method Details

  - ### getInstance

    public static Currency getInstance(String currencyCode)
    Returns the `Currency` instance for the given currency code.
    Parameters:
      `currencyCode` - the ISO 4217 code of the currency
    Returns:
      the `Currency` instance for the given currency code
    Throws:
      `NullPointerException` - if `currencyCode` is null
      `IllegalArgumentException` - if `currencyCode` is not a supported ISO 4217 code.

  - ### getInstance

    public static Currency getInstance(Locale locale)
    Returns the `Currency` instance for the country of the given locale. The language and variant components of the locale are ignored. The result may vary over time, as countries change their currencies. For example, for the original member countries of the European Monetary Union, the method returns the old national currencies until December 31, 2001, and the Euro from January 1, 2002, local time of the respective countries.

    If the specified `locale` contains "cu" and/or "rg" Unicode extensions, the instance returned from this method reflects the values specified with those extensions. If both "cu" and "rg" are specified, the currency from the "cu" extension supersedes the implicit one from the "rg" extension.

    The method returns `null` for territories that don't have a currency, such as Antarctica.

    Parameters:
      `locale` - the locale for whose country a `Currency` instance is needed
    Returns:
      the `Currency` instance for the country of the given locale, or `null`
    Throws:
      `NullPointerException` - if `locale` is `null`
      `IllegalArgumentException` - if the country of the given `locale` is not a supported ISO 3166 country code.

  - ### getAvailableCurrencies

    public static Set<Currency> getAvailableCurrencies()
    Gets the set of available currencies. The returned set of currencies contains all of the available currencies, which may include currencies that represent obsolete ISO 4217 codes. The set can be modified without affecting the available currencies in the runtime.
    Returns:
      the set of available currencies. If there is no currency available in the runtime, the returned set is empty.
    Since:
      1.7

  - ### getCurrencyCode

    public String getCurrencyCode()
    Gets the ISO 4217 currency code of this currency.
    Returns:
      the ISO 4217 currency code of this currency.

  - ### getSymbol

    public String getSymbol()
    Gets the symbol of this currency for the default `DISPLAY` locale. For example, for the US Dollar, the symbol is "$" if the default locale is the US, while for other locales it may be "US$". If no symbol can be determined, the ISO 4217 currency code is returned.

    If the default `DISPLAY` locale contains "rg" (region override) Unicode extensions, the symbol returned from this method reflects the value specified with that extension.

    This is equivalent to calling `getSymbol(Locale.getDefault(Locale.Category.DISPLAY))`.

    Returns:
      the symbol of this currency for the default `DISPLAY` locale

  - ### getSymbol

    public String getSymbol(Locale locale)
    Gets the symbol of this currency for the specified locale. For example, for the US Dollar, the symbol is "$" if the specified locale is the US, while for other locales it may be "US$". If no symbol can be determined, the ISO 4217 currency code is returned.

    If the specified `locale` contains "rg" (region override) Unicode extensions, the symbol returned from this method reflects the value specified with that extension.

    Parameters:
      `locale` - the locale for which a display name for this currency is needed
    Returns:
      the symbol of this currency for the specified locale
    Throws:
      `NullPointerException` - if `locale` is null

  - ### getDefaultFractionDigits

    public int getDefaultFractionDigits()
    Gets the default number of fraction digits used with this currency. Note that the number of fraction digits is the same as ISO 4217's minor unit for the currency. For example, the default number of fraction digits for the Euro is 2, while for the Japanese Yen it's 0. In the case of pseudo-currencies, such as IMF Special Drawing Rights, -1 is returned.
    Returns:
      the default number of fraction digits used with this currency

  - ### getNumericCode

    public int getNumericCode()
    Returns the ISO 4217 numeric code of this currency.
    Returns:
      the ISO 4217 numeric code of this currency
    Since:
      1.7

  - ### getNumericCodeAsString

    public String getNumericCodeAsString()
    Returns the 3 digit ISO 4217 numeric code of this currency as a `String`. Unlike `getNumericCode()`, which returns the numeric code as `int`, this method always returns the numeric code as a 3 digit string. e.g. a numeric value of 32 would be returned as "032", and a numeric value of 6 would be returned as "006".
    Returns:
      the 3 digit ISO 4217 numeric code of this currency as a `String`
    Since:
      9

  - ### getDisplayName

    public String getDisplayName()
    Gets the name that is suitable for displaying this currency for the default `DISPLAY` locale. If there is no suitable display name found for the default locale, the ISO 4217 currency code is returned.

    This is equivalent to calling `getDisplayName(Locale.getDefault(Locale.Category.DISPLAY))`.

    Returns:
      the display name of this currency for the default `DISPLAY` locale
    Since:
      1.7

  - ### getDisplayName

    public String getDisplayName(Locale locale)
    Gets the name that is suitable for displaying this currency for the specified locale. If there is no suitable display name found for the specified locale, the ISO 4217 currency code is returned.
    Parameters:
      `locale` - the locale for which a display name for this currency is needed
    Returns:
      the display name of this currency for the specified locale
    Throws:
      `NullPointerException` - if `locale` is null
    Since:
      1.7

  - ### toString

    public String toString()
    Returns the ISO 4217 currency code of this currency.
    Overrides:
      `toString` in class `Object`
    Returns:
      the ISO 4217 currency code of this currency