001/**
002 * Copyright (c) 2012, 2014, Credit Suisse (Anatole Tresch), Werner Keil and others by the @author tag.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
005 * use this file except in compliance with the License. You may obtain a copy of
006 * the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
012 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
013 * License for the specific language governing permissions and limitations under
014 * the License.
015 */
016package org.javamoney.moneta.internal.convert;
017
018import java.math.BigDecimal;
019
020import javax.money.convert.*;
021
022import org.javamoney.moneta.ExchangeRateBuilder;
023import org.javamoney.moneta.spi.AbstractRateProvider;
024import org.javamoney.moneta.spi.DefaultNumberValue;
025
026/**
027 * This class implements an {@link javax.money.convert.ExchangeRateProvider} that provides exchange rate with factor
028 * one for identical base/term currencies.
029 *
030 * @author Anatole Tresch
031 * @author Werner Keil
032 */
033public class IdentityRateProvider extends AbstractRateProvider {
034
035    /**
036     * The {@link javax.money.convert.ConversionContext} of this provider.
037     */
038    private static final ProviderContext CONTEXT =
039            ProviderContextBuilder.of("IDENT", RateType.OTHER).set("providerDescription", "Identitiy Provider").build();
040
041    /**
042     * Constructor, also loads initial data.
043     */
044    public IdentityRateProvider() {
045        super(CONTEXT);
046    }
047
048    /**
049     * Check if this provider can provide a rate, which is only the case if base and term are equal.
050     *
051     * @param conversionQuery the required {@link ConversionQuery}, not {@code null}
052     * @return true, if the contained base and term currencies are known to this provider.
053     */
054    public boolean isAvailable(ConversionQuery conversionQuery) {
055        return conversionQuery.getBaseCurrency().getCurrencyCode()
056                .equals(conversionQuery.getCurrency().getCurrencyCode());
057    }
058
059    public ExchangeRate getExchangeRate(ConversionQuery conversionQuery) {
060        if (conversionQuery.getBaseCurrency().getCurrencyCode().equals(conversionQuery.getCurrency().getCurrencyCode())) {
061            ExchangeRateBuilder builder = new ExchangeRateBuilder(getContext().getProviderName(), RateType.OTHER)
062                    .setBase(conversionQuery.getBaseCurrency());
063            builder.setTerm(conversionQuery.getCurrency());
064            builder.setFactor(DefaultNumberValue.of(BigDecimal.ONE));
065            return builder.build();
066        }
067        return null;
068    }
069
070    /*
071     * (non-Javadoc)
072         *
073         * @see
074         * javax.money.convert.ExchangeRateProvider#getReversed(javax.money.convert
075         * .ExchangeRate)
076         */
077    @Override
078    public ExchangeRate getReversed(ExchangeRate rate) {
079        if (rate.getContext().getProviderName().equals(CONTEXT.getProviderName())) {
080            return new ExchangeRateBuilder(rate.getContext()).setTerm(rate.getBaseCurrency())
081                    .setBase(rate.getCurrency()).setFactor(new DefaultNumberValue(BigDecimal.ONE)).build();
082        }
083        return null;
084    }
085
086}