1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/task4/solution12/test/org/apidesign/apifest08/test/Task1Test.java Sat Oct 11 23:38:46 2008 +0200
1.3 @@ -0,0 +1,174 @@
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 +
1.10 +import org.apidesign.apifest08.currency.Convertor;
1.11 +import org.apidesign.apifest08.currency.exceptions.InvalidCurrencyException;
1.12 +import org.apidesign.apifest08.currency.exceptions.UnknownConvertorException;
1.13 +
1.14 +/**
1.15 + * Finish the Convertor API, and then write bodies of methods inside of this class to match the given tasks. To fullfil
1.16 + * your task, use the API define in the <code>org.apidesign.apifest08.currency</code> package. Do not you reflection, or
1.17 + * other hacks as your code shall run without any runtime permissions.
1.18 + */
1.19 +public class Task1Test extends TestCase {
1.20 + public Task1Test(String testName) {
1.21 + super(testName);
1.22 + }
1.23 +
1.24 + @Override
1.25 + protected void setUp() throws Exception {
1.26 + }
1.27 +
1.28 + @Override
1.29 + protected void tearDown() throws Exception {
1.30 + }
1.31 +
1.32 + //
1.33 + // Imagine that there are three parts of the whole system:
1.34 + // 1. there is someone who knows the current exchange rate
1.35 + // 2. there is someone who wants to do the conversion
1.36 + // 3. there is the API between 1. and 2. which allows them to communicate
1.37 + // Please design such API
1.38 + //
1.39 +
1.40 + /**
1.41 + * Create convertor that understands two currencies, CZK and USD. Make 1 USD == 17 CZK. This is a method provided for
1.42 + * #1 group - e.g. those that know the exchange rate. They somehow need to create the objects from the API and tell
1.43 + * them the exchange rate. The API itself knows nothing about any rates, before the createCZKtoUSD method is called.
1.44 + * Creation of the convertor shall not require subclassing of any class or interface on the client side.
1.45 + * @return prepared convertor ready for converting USD to CZK and CZK to USD
1.46 + */
1.47 + public static Convertor createCZKtoUSD() {
1.48 + // set exchange rates
1.49 + Convertor.setConvertorRates(Currency.getInstance("USD"), Currency.getInstance("CZK"), 17d, 1d);
1.50 +
1.51 + // create new instance
1.52 + Convertor convertor = null;
1.53 + try {
1.54 + convertor = Convertor.getConvertorInstance(Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.55 + } catch (UnknownConvertorException e) {
1.56 + e.printStackTrace();
1.57 + }
1.58 +
1.59 + return convertor;
1.60 + }
1.61 +
1.62 + /**
1.63 + * Create convertor that understands two currencies, CZK and SKK. Make 100 SKK == 80 CZK. Again this is method for the
1.64 + * #1 group - it knows the exchange rate, and needs to use the API to create objects with the exchange rate. Anyone
1.65 + * shall be ready to call this method without any other method being called previously. The API itself shall know
1.66 + * nothing about any rates, before this method is called. Creation of the convertor shall not require subclassing of
1.67 + * any class or interface on the client side.
1.68 + * @return prepared convertor ready for converting SKK to CZK and CZK to SKK
1.69 + */
1.70 + public static Convertor createSKKtoCZK() {
1.71 + // set exchange rates
1.72 + Convertor.setConvertorRates(Currency.getInstance("SKK"), Currency.getInstance("CZK"), 80d, 100d);
1.73 +
1.74 + // create new instance
1.75 + Convertor convertor = null;
1.76 + try {
1.77 + convertor = Convertor.getConvertorInstance(Currency.getInstance("SKK"), Currency.getInstance("CZK"));
1.78 + } catch (UnknownConvertorException e) {
1.79 + e.printStackTrace();
1.80 + }
1.81 +
1.82 + return convertor;
1.83 + }
1.84 +
1.85 + //
1.86 + // now the methods for group #2 follow:
1.87 + // this group knows nothing about exchange rates, but knows how to use
1.88 + // the API to do conversions. It somehow (by calling one of the factory
1.89 + // methods) gets objects from the API and uses them to do the conversions.
1.90 + //
1.91 +
1.92 + /**
1.93 + * Use the convertor from <code>createCZKtoUSD</code> method and do few conversions with it.
1.94 + */
1.95 + public void testCurrencyCZKUSD() throws Exception {
1.96 + Convertor c = createCZKtoUSD();
1.97 + // convert $5 to CZK using c:
1.98 + double result = c.convert(5, Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.99 + assertEquals("Result is not 85 CZK", 85.0, result);
1.100 +
1.101 + // convert $8 to CZK
1.102 + result = c.convert(8, Currency.getInstance("USD"), Currency.getInstance("CZK"));
1.103 + assertEquals("Result is not 136 CZK", 136.0, result);
1.104 +
1.105 + // convert 1003CZK to USD
1.106 + result = c.convert(1003, Currency.getInstance("CZK"), Currency.getInstance("USD"));
1.107 + assertEquals("Result is not 59 USD", 59.0, result);
1.108 + }
1.109 +
1.110 + /**
1.111 + * Use the convertor from <code>createSKKtoCZK</code> method and do few conversions with it.
1.112 + */
1.113 + public void testCurrencySKKCZK() throws Exception {
1.114 + Convertor c = createSKKtoCZK();
1.115 +
1.116 + // convert 16CZK using c:
1.117 + double result = c.convert(16, Currency.getInstance("CZK"), Currency.getInstance("SKK"));
1.118 + assertEquals("Result is not 20 SKK", 20.0, result);
1.119 +
1.120 + // convert 500SKK to CZK
1.121 + result = c.convert(500, Currency.getInstance("SKK"), Currency.getInstance("CZK"));
1.122 + assertEquals("Result is not 400 CZK", 400.0, result);
1.123 + }
1.124 +
1.125 + /**
1.126 + * Verify that the CZK to USD convertor knows nothing about SKK.
1.127 + */
1.128 + public void testCannotConvertToSKKwithCZKUSDConvertor() throws Exception {
1.129 + Convertor c = createCZKtoUSD();
1.130 + boolean exceptionThrown = false;
1.131 +
1.132 + // convert $5 to SKK, the API shall say this is not possible
1.133 + try {
1.134 + c.convert(5, Currency.getInstance("USD"), Currency.getInstance("SKK"));
1.135 + exceptionThrown = false;
1.136 + } catch (InvalidCurrencyException e) {
1.137 + exceptionThrown = true;
1.138 + }
1.139 + assertEquals("It should be impossible to convert to SKK with USD->CZK convertor", true, exceptionThrown);
1.140 +
1.141 + // convert 500 SKK to CZK, the API shall say this is not possible
1.142 + try {
1.143 + c.convert(500, Currency.getInstance("SKK"), Currency.getInstance("CZK"));
1.144 + exceptionThrown = false;
1.145 + } catch (InvalidCurrencyException e) {
1.146 + exceptionThrown = true;
1.147 + }
1.148 + assertEquals("It should be impossible to convert from SKK with USD->CZK convertor", true, exceptionThrown);
1.149 +
1.150 + }
1.151 +
1.152 + /**
1.153 + * Verify that the CZK to SKK convertor knows nothing about USD.
1.154 + */
1.155 + public void testCannotConvertToSKKwithSKKCZKConvertor() throws Exception {
1.156 + Convertor c = createSKKtoCZK();
1.157 + boolean exceptionThrown = false;
1.158 +
1.159 + // convert $5 to SKK, the API shall say this is not possible
1.160 + try {
1.161 + c.convert(5, Currency.getInstance("USD"), Currency.getInstance("SKK"));
1.162 + exceptionThrown = false;
1.163 + } catch (InvalidCurrencyException e) {
1.164 + exceptionThrown = true;
1.165 + }
1.166 + assertEquals("It should be impossible to convert form USD with SKK->CZK convertor", true, exceptionThrown);
1.167 +
1.168 + // convert 500 CZK to USD, the API shall say this is not possible
1.169 + try {
1.170 + c.convert(500, Currency.getInstance("CZK"), Currency.getInstance("USD"));
1.171 + exceptionThrown = false;
1.172 + } catch (InvalidCurrencyException e) {
1.173 + exceptionThrown = true;
1.174 + }
1.175 + assertEquals("It should be impossible to convert to USD with SKK->CZK convertor", true, exceptionThrown);
1.176 + }
1.177 +}