1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/task3/solution02/test/org/apidesign/apifest08/test/Task1Test.java Tue Oct 07 11:05:34 2008 +0200
1.3 @@ -0,0 +1,160 @@
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.ConvertorFactory;
1.12 +import org.apidesign.apifest08.currency.MoneyImpl;
1.13 +
1.14 +/** Finish the Convertor API, and then write bodies of methods inside
1.15 + * of this class to match the given tasks. To fullfil your task, use the
1.16 + * API define in the <code>org.apidesign.apifest08.currency</code> package.
1.17 + * Do not you reflection, or other hacks as your code
1.18 + * shall run without any runtime permissions.
1.19 + */
1.20 +public class Task1Test extends TestCase {
1.21 +
1.22 + public static final Currency USD = Currency.getInstance("USD");
1.23 + public static final Currency CZK = Currency.getInstance("CZK");
1.24 + public static final Currency SKK = Currency.getInstance("SKK");
1.25 +
1.26 + public Task1Test(String testName) {
1.27 + super(testName);
1.28 + }
1.29 +
1.30 + @Override
1.31 + protected void setUp() throws Exception {
1.32 + }
1.33 +
1.34 + @Override
1.35 + protected void tearDown() throws Exception {
1.36 + }
1.37 +
1.38 + //
1.39 + // Imagine that there are three parts of the whole system:
1.40 + // 1. there is someone who knows the current exchange rate
1.41 + // 2. there is someone who wants to do the conversion
1.42 + // 3. there is the API between 1. and 2. which allows them to communicate
1.43 + // Please design such API
1.44 + //
1.45 +
1.46 + /** Create convertor that understands two currencies, CZK and
1.47 + * USD. Make 1 USD == 17 CZK. This is a method provided for #1 group -
1.48 + * e.g. those that know the exchange rate. They somehow need to create
1.49 + * the objects from the API and tell them the exchange rate. The API itself
1.50 + * knows nothing about any rates, before the createCZKtoUSD method is called.
1.51 + *
1.52 + * Creation of the convertor shall not require subclassing of any class
1.53 + * or interface on the client side.
1.54 + *
1.55 + * @return prepared convertor ready for converting USD to CZK and CZK to USD
1.56 + */
1.57 + public static Convertor createCZKtoUSD() {
1.58 + return ConvertorFactory.createConvertor(new MoneyImpl(17,CZK), new MoneyImpl(1,USD));
1.59 + }
1.60 +
1.61 + /** Create convertor that understands two currencies, CZK and
1.62 + * SKK. Make 100 SKK == 80 CZK. Again this is method for the #1 group -
1.63 + * it knows the exchange rate, and needs to use the API to create objects
1.64 + * with the exchange rate. Anyone shall be ready to call this method without
1.65 + * any other method being called previously. The API itself shall know
1.66 + * nothing about any rates, before this method is called.
1.67 + *
1.68 + * Creation of the convertor shall not require subclassing of any class
1.69 + * or interface on the client side.
1.70 + *
1.71 + * @return prepared convertor ready for converting SKK to CZK and CZK to SKK
1.72 + */
1.73 + public static Convertor createSKKtoCZK() {
1.74 + return ConvertorFactory.createConvertor(new MoneyImpl(100,SKK), new MoneyImpl(80,CZK));
1.75 + }
1.76 +
1.77 + //
1.78 + // now the methods for group #2 follow:
1.79 + // this group knows nothing about exchange rates, but knows how to use
1.80 + // the API to do conversions. It somehow (by calling one of the factory
1.81 + // methods) gets objects from the API and uses them to do the conversions.
1.82 + //
1.83 +
1.84 + /** Use the convertor from <code>createCZKtoUSD</code> method and do few conversions
1.85 + * with it.
1.86 + */
1.87 + public void testCurrencyCZKUSD() throws Exception {
1.88 + Convertor c = createCZKtoUSD();
1.89 + // convert $5 to CZK using c:
1.90 + assertEquals("Result is 85 CZK",new MoneyImpl(85,CZK), c.convert(new MoneyImpl(5,USD),CZK));
1.91 +
1.92 + // convert $8 to CZK
1.93 + assertEquals("Result is 136 CZK",new MoneyImpl(136,CZK), c.convert(new MoneyImpl(8,USD),CZK));
1.94 +
1.95 + // convert 1003CZK to USD
1.96 + assertEquals("Result is 59 USD", new MoneyImpl(59,USD), c.convert(new MoneyImpl(1003,CZK),USD));
1.97 +
1.98 + }
1.99 +
1.100 + /** Use the convertor from <code>createSKKtoCZK</code> method and do few conversions
1.101 + * with it.
1.102 + */
1.103 + public void testCurrencySKKCZK() throws Exception {
1.104 + Convertor c = createSKKtoCZK();
1.105 + // convert 16CZK using c:
1.106 + assertEquals("Result is 20 SKK", new MoneyImpl(20,SKK), c.convert(new MoneyImpl(16,CZK),SKK));
1.107 +
1.108 + // convert 500SKK to CZK
1.109 + assertEquals("Result is 400 CZK", new MoneyImpl(400,CZK), c.convert(new MoneyImpl(500,SKK),CZK));
1.110 + }
1.111 +
1.112 + /** Verify that the CZK to USD convertor knows nothing about SKK.
1.113 + */
1.114 + public void testCannotConvertToSKKwithCZKUSDConvertor() throws Exception {
1.115 + Convertor c = createCZKtoUSD();
1.116 + // convert $5 to SKK, the API shall say this is not possible
1.117 + try
1.118 + {
1.119 + c.convert(new MoneyImpl(5, USD), SKK);
1.120 + fail("Exception expected");
1.121 + }
1.122 + catch(IllegalArgumentException e)
1.123 + {
1.124 + assertTrue("Ok",true);
1.125 + }
1.126 + // convert 500 SKK to CZK, the API shall say this is not possible
1.127 + try
1.128 + {
1.129 + c.convert(new MoneyImpl(500, SKK), CZK);
1.130 + fail("Exception expected");
1.131 + }
1.132 + catch(IllegalArgumentException e)
1.133 + {
1.134 + assertTrue("Ok",true);
1.135 + }
1.136 + }
1.137 +
1.138 + /** Verify that the CZK to SKK convertor knows nothing about USD.
1.139 + */
1.140 + public void testCannotConvertToUSDwithCZKSKKConvertor() throws Exception {
1.141 + Convertor c = createSKKtoCZK();
1.142 + // convert $5 to SKK, the API shall say this is not possible
1.143 + try
1.144 + {
1.145 + c.convert(new MoneyImpl(5, USD), SKK);
1.146 + fail("Exception expected");
1.147 + }
1.148 + catch(IllegalArgumentException e)
1.149 + {
1.150 + assertTrue("Ok",true);
1.151 + }
1.152 + // convert 500 CZK to USD, the API shall say this is not possible
1.153 + try
1.154 + {
1.155 + c.convert(new MoneyImpl(500, CZK), USD);
1.156 + fail("Exception expected");
1.157 + }
1.158 + catch(IllegalArgumentException e)
1.159 + {
1.160 + assertTrue("Ok",true);
1.161 + }
1.162 + }
1.163 +}