Kotlin extensions for javax.money (Moneta) JSR 354

Extensions which makes working with javax.money JSR 354 with easier when using Kotlin.

This code builds upon the Money API of the JSR proposal, not the Moneta classes in the reference implementation.

Features

• Kotlin extension functions for all the *Builder in the javax.money package.
• Kotlin operator functions for the operators defined in javax.money.MonetaryAmount.

Requirements

At least Java 21.

At least Kotlin 2.

Installation

Find the latest version on Maven Central.

Add the money-kotlin dependency to your project.

Gradle:

implementation("nl.hiddewieringa:money-kotlin:$moneyKotlinVersion")

Maven:

<dependency>
  <groupId>nl.hiddewieringa</groupId>
  <artifactId>money-kotlin</artifactId>
  <version>${moneyKotlin.version}</version>
</dependency>

This library depends only on the Money API of the JSR proposal. Ensure you add a dependency on a specific implementation such as org.javamoney:moneta:<version>.

Examples

All the extension/operator functions have an associated test in src/test/kotlin.

Monetary amount

// Create a monetary amount of a specific type and currency
val money = (10.0).ofCurrency<FastMoney>("EUR")

// Create a monetary amount of a default type for the provider and currency.
// If using Moneta, its default type is Money and can be changed by specifying 
// org.javamoney.moneta.Money.defaults.amountType in the javamoney.properties.
val money = (10.0).ofCurrency("EUR")
//or
val money = (10.0).ofCurrency<MonetaryAmount>("EUR")

// add
money + money
+money
// subtract & negate
money - money
-money
// multiply
money * 2
2 * money
// divide & remainder
money / 2.0
money % 2.0

monetaryAmountFactoryQuery {
    setFixedScale(true)
}
monetaryContext {
    setPrecision(1)
}
typedMonetaryContext<FastMoney> {
    setPrecision(1)
}

Currency

"EUR".asCurrency()

currencyContext("PROVIDER") {
    setProviderName("PROVIDER")
}
currencyQuery {
    setCountries("NL".asCountryLocale())
}

Locale

"NL".asCountryLocale()
"NL".asCountryLocale().getCurrency()
"NL".asCountryLocale().getCurrencies()

Rounding

roundingContext("EUR", "PROVIDER") {
    setProviderName("PROVIDER")
}
roundingQuery {
    setScale(1)
}

Format

Locale.GERMANY.monetaryAmountFormat()

amountFormatContext {
    setFormatName("name")
}
amountFormatContext(Locale.GERMANY) {
    setFormatName("name")
}
amountFormatQuery("name") {
    setLocale(Locale.GERMANY)
}

Conversion

money.convertTo("EUR")
money.convertTo("EUR", provider)

providerContext("PROVIDER", RateType.ANY) {
    setProviderName("PROVIDER")
}
conversionContext {
    setRateType(RateType.ANY)
}
conversionQuery {
    setBaseCurrency("EUR")
}

Releasing and publishing

Preparation

Ensure that the properties signing.keyId, signing.password and signing.secretKeyRingFile= are set in ~/.gradle/gradle.properties. These properties are neccesary for signing releases.

Ensure that the properties sonatypeUsername and sonatypePassword are set in ~/.gradle/gradle.properties. These properties are credentials for publishing to Maven Central.

Building

Build the project

./gradlew clean build

Releasing

Release a version by tagging a Git commit

git tag -a 1.0.0 -m "Version 1.0.0"

Publishing

Publish the release to Sonatype

./gradlew publishToSonatype closeAndReleaseSonatypeStagingRepository

This will publish the artifacts to Maven Central.