icu4j/main/classes/core/src/com/ibm/icu/number/CurrencyPrecision.java

// © 2017 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
package com.ibm.icu.number;

import com.ibm.icu.util.Currency;

/**
 * A class that defines a rounding strategy parameterized by a currency to be used when formatting
 * numbers in NumberFormatter.
 *
 * <p>
 * To create a CurrencyPrecision, use one of the factory methods on Precision.
 *
 * @stable ICU 60
 * @see NumberFormatter
 */
public abstract class CurrencyPrecision extends Precision {

    /* package-private */ CurrencyPrecision() {
    }

    /**
     * Associates a currency with this rounding strategy.
     *
     * <p>
     * <strong>Calling this method is <em>not required</em></strong>, because the currency specified in
     * unit() or via a CurrencyAmount passed into format(Measure) is automatically applied to currency
     * rounding strategies. However, this method enables you to override that automatic association.
     *
     * <p>
     * This method also enables numbers to be formatted using currency rounding rules without explicitly
     * using a currency format.
     *
     * @param currency
     *            The currency to associate with this rounding strategy.
     * @return A Precision for chaining or passing to the NumberFormatter rounding() setter.
     * @throws IllegalArgumentException for null Currency
     * @stable ICU 60
     * @see NumberFormatter
     */
    public Precision withCurrency(Currency currency) {
        if (currency != null) {
            return constructFromCurrency(this, currency);
        } else {
            throw new IllegalArgumentException("Currency must not be null");
        }
    };
}