001/**
002 * Copyright (c) 2012, 2015, 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.function;
017
018import javax.money.CurrencyUnit;
019import javax.money.MonetaryAmount;
020
021/**
022 * A state object for collecting statistics such as count, min, max, sum, and
023 * average.
024 * @author otaviojava
025 * @author Anatole Tresch
026 */
027public interface MonetarySummaryStatistics {
028
029        /**
030         * Records another value into the summary information.
031         * @param amount
032         *            the input amount value to be added, not null.
033         */
034        void accept(MonetaryAmount amount);
035
036        /**
037         * Combines the state of another {@code MonetarySummaryStatistics} into this
038         * one.
039         * @param summaryStatistics
040         *            another {@code MonetarySummaryStatistics}, not null.
041         */
042        MonetarySummaryStatistics combine(
043                        MonetarySummaryStatistics summaryStatistics);
044
045   /**
046     * Get the number of items added to this summary instance.
047     * @return the number of summarized items, >= 0.
048     */
049    long getCount();
050
051    /**
052     * Get the minimal amount found within this summary.
053     * @return the minimal amount, or null if no amount was added to this summary instance.
054     */
055        MonetaryAmount getMin();
056
057    /**
058     * Get the maximal amount found within this summary.
059     * @return the minimal amount, or null if no amount was added to this summary instance.
060     */
061        MonetaryAmount getMax();
062
063    /**
064     * Get the sum of all amounts within this summary.
065     * @return the total amount, or null if no amount was added to this summary instance.
066     */
067        MonetaryAmount getSum();
068
069    /**
070     * Get the mean average of all amounts added.
071     * @return the mean average amount, or null if no amount was added to this summary instance.
072     */
073        MonetaryAmount getAverage();
074
075        /**
076         * the currency unit used in summary
077         * @return the currency unit
078         */
079        CurrencyUnit getCurrencyUnit();
080
081        /**
082         * return if is possible do exchange rate or not with the MonetarySummary
083         * @return false;
084         */
085        boolean isExchangeable();
086
087        /**
088         * created the MonetarySummaryStatistics converted to {@link CurrencyUnit}
089         * @param unit
090         *            to be converted
091         * @return MonetarySummaryStatistics converted
092         * @throws UnsupportedOperationException
093         *             if {@link MonetarySummaryStatistics#isExchangeable()} was
094         *             false
095         * @throws NullPointerException
096         *             if unit was null
097         */
098        MonetarySummaryStatistics to(CurrencyUnit unit);
099
100}