1.1 --- a/task4/solution12/test/org/apidesign/apifest08/test/Task3Test.java Fri Oct 17 17:54:38 2008 +0200
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,145 +0,0 @@
1.4 -package org.apidesign.apifest08.test;
1.5 -
1.6 -import java.util.Currency;
1.7 -
1.8 -import junit.framework.TestCase;
1.9 -import org.apidesign.apifest08.currency.Convertor;
1.10 -import org.apidesign.apifest08.currency.exceptions.UnknownConvertorException;
1.11 -
1.12 -/** The exchange rates are not always the same. They are changing. Day by day,
1.13 - * hour by hour, minute by minute. For every bank it is important to always
1.14 - * have the actual exchange rate available in the system. That is why let's
1.15 - * create a pluggable convertor that will always have up to date value of its
1.16 - * exchange rate.
1.17 - * <p>
1.18 - * The quest for today is to allow 3rd party developer to write a convertor
1.19 - * that adjusts its exchange rate everytime it is queried. This convertor is
1.20 - * written by independent vendor, the vendor knows only your Convertor API,
1.21 - * he does not know how the whole system looks and how the convertor is supposed
1.22 - * to be used.
1.23 - */
1.24 -public class Task3Test extends TestCase {
1.25 -
1.26 - private static double actualRate;
1.27 - private static boolean increasing;
1.28 -
1.29 - private static final double EXCHANGE_RATE_MAX = 16.0;
1.30 - private static final double EXCHANGE_RATE_MIN = 15.0;
1.31 -
1.32 - public Task3Test(String testName) {
1.33 - super(testName);
1.34 - }
1.35 -
1.36 - @Override
1.37 - protected void setUp() throws Exception {
1.38 - }
1.39 -
1.40 - @Override
1.41 - protected void tearDown() throws Exception {
1.42 - }
1.43 -
1.44 - // Backward compatibly enhance your existing API to support following
1.45 - // usecases:
1.46 - //
1.47 -
1.48 -
1.49 - /** Without knowing anything about the surrounding system, write an
1.50 - * implementation of convertor that will return different rates everytime
1.51 - * it is queried. Convert USD to CZK and vice versa. Start with the rate of
1.52 - * 1USD = 16CZK and adjust it in favor of CZK by 0.01 CZK with every query.
1.53 - * As soon as you reach 1USD = 15CZK adjust it by 0.01 CZK in favor of USD
1.54 - * until you reach 1USD = 16CZK
1.55 - *
1.56 - * @return new instance of "online" USD and CZK convertor starting with rate 1USD = 16CZK
1.57 - */
1.58 - public static Convertor createOnlineCZKUSDConvertor() {
1.59 - actualRate = 16.01;
1.60 - increasing = false;
1.61 -
1.62 - // sets actual exchange rates
1.63 - setRates();
1.64 -
1.65 - // create new instance
1.66 - Convertor convertor = null;
1.67 - try {
1.68 - convertor = Convertor.getConvertorInstance(Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.69 - } catch (UnknownConvertorException e) {
1.70 - e.printStackTrace();
1.71 - }
1.72 -
1.73 - return convertor;
1.74 - }
1.75 -
1.76 - public void testFewQueriesForOnlineConvertor() throws Exception {
1.77 - Convertor c = createOnlineCZKUSDConvertor();
1.78 - doFewQueriesForOnlineConvertor(c);
1.79 - }
1.80 -
1.81 - static void doFewQueriesForOnlineConvertor(Convertor c) throws Exception {
1.82 - // convert $5 to CZK using c:
1.83 - double result = c.convert(5d, Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.84 - double expectedResult = actualRate * 5;
1.85 - assertEquals("Result is not " + expectedResult + " CZK", expectedResult, result);
1.86 -
1.87 - // change exchange rates
1.88 - setRates();
1.89 -
1.90 - // convert $8 to CZK using c:
1.91 - result = c.convert(8d, Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.92 - expectedResult = actualRate * 8;
1.93 - assertEquals("Result is not " + expectedResult + " CZK", expectedResult, result);
1.94 -
1.95 - // change exchange rates
1.96 - setRates();
1.97 -
1.98 - // convert $1 to CZK using c:
1.99 - result = c.convert(1d, Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.100 - expectedResult = actualRate * 1;
1.101 - assertEquals("Result is not " + expectedResult + " CZK", expectedResult, result);
1.102 -
1.103 - // change exchange rates
1.104 - setRates();
1.105 -
1.106 - // convert 15.97CZK to USD using c:
1.107 - result = c.convert(15.97d, Currency.getInstance("CZK"), Currency.getInstance("USD"));
1.108 - expectedResult = 15.97 / actualRate ;
1.109 - assertEquals("Result is not " + expectedResult + " USD", expectedResult, result);
1.110 - }
1.111 -
1.112 - /** Join the convertors and show they behave sane.
1.113 - */
1.114 - public void testOnlineConvertorComposition() throws Exception {
1.115 - Convertor c = Task2Test.merge(
1.116 - createOnlineCZKUSDConvertor(),
1.117 - Task1Test.createSKKtoCZK()
1.118 - );
1.119 -
1.120 - // convert 16CZK to SKK using c:
1.121 - double result = c.convert(16d, Currency.getInstance("CZK"), Currency.getInstance("SKK"));
1.122 - assertEquals("Result is not 20 SKK", 20d, result);
1.123 -
1.124 - // convert 500SKK to CZK using c:
1.125 - result = c.convert(500d, Currency.getInstance("SKK"), Currency.getInstance("CZK"));
1.126 - assertEquals("Result is not 400 CZK", 400d, result);
1.127 -
1.128 - doFewQueriesForOnlineConvertor(c);
1.129 - }
1.130 -
1.131 - private static void setRates() {
1.132 - // logic for change of actual exchange rate
1.133 - if(increasing) {
1.134 - actualRate += 0.01;
1.135 - if(actualRate == EXCHANGE_RATE_MAX){
1.136 - increasing = false;
1.137 - }
1.138 - } else {
1.139 - actualRate -= 0.01;
1.140 - if(actualRate == EXCHANGE_RATE_MIN){
1.141 - increasing = true;
1.142 - }
1.143 - }
1.144 -
1.145 - // set exchange rates
1.146 - Convertor.setConvertorRates(Currency.getInstance("USD"), Currency.getInstance("CZK"), actualRate, 1d);
1.147 - }
1.148 -}