diff -r 09d690bb97f6 -r 58ec6da75f6f task4/solution11/test/org/apidesign/apifest08/test/Task2Test.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/task4/solution11/test/org/apidesign/apifest08/test/Task2Test.java Sat Oct 11 23:38:46 2008 +0200
@@ -0,0 +1,140 @@
+package org.apidesign.apifest08.test;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import junit.framework.TestCase;
+import org.apidesign.apifest08.currency.Convertor;
+import org.apidesign.apifest08.currency.CurrencyValue;
+import org.apidesign.apifest08.currency.ExchangeRateValue;
+
+/** There are many currencies around the world and many banks manipulate
+ * with more than one or two at the same time. As banks are usually the
+ * best paying clients, which is true even in case of your Convertor API,
+ * it is reasonable to listen to their requests.
+ *
+ * The quest for today is to enhance your existing convertor API to hold
+ * information about many currencies and allow conversions between any of them.
+ * Also, as conversion rates for diferent currencies usually arise from various
+ * bank departments, there is another important need. There is a need to
+ * compose two convertors into one by merging all the information about
+ * currencies they know about.
+ */
+public class Task2Test extends TestCase {
+
+ public Task2Test(String testName) {
+ super(testName);
+ }
+
+ @Override
+ protected void setUp() throws Exception {
+ }
+
+ @Override
+ protected void tearDown() throws Exception {
+ }
+
+ // As in Task1Test, keep in mind, that there are three parts
+ // of the whole system:
+ // 1. there is someone who knows the current exchange rate
+ // 2. there is someone who wants to do the conversion
+ // 3. there is the API between 1. and 2. which allows them to communicate
+ //
+ // Please backward compatibly enhance your existing API to support following
+ // usecases:
+ //
+ /** Create convertor that understands two currencies, CZK and
+ * SKK. Make 100 SKK == 75 CZK. This is method for the group of users that
+ * knows the exchange rate, and needs to use the API to create objects
+ * with the exchange rate. Anyone shall be ready to call this method without
+ * any other method being called previously. The API itself shall know
+ * nothing about any rates, before this method is called.
+ */
+ public static Convertor createTripleConvertor() {
+ // Rates: 1USD = 15CZK
+ // Rates: 1USD = 20SKK
+ // Rates: 75CZK = 100SKK
+ Collection> exchangeRates =
+ new ArrayList>();
+ exchangeRates.add(ExchangeRateValue.getExchangeRate(
+ CurrencyValue.getCurrencyValue(1d, "USD"),
+ CurrencyValue.getCurrencyValue(15d, "CZK")));
+ exchangeRates.add(ExchangeRateValue.getExchangeRate(
+ CurrencyValue.getCurrencyValue(1d, "USD"),
+ CurrencyValue.getCurrencyValue(20d, "SKK")));
+ exchangeRates.add(ExchangeRateValue.getExchangeRate(
+ CurrencyValue.getCurrencyValue(75d, "CZK"),
+ CurrencyValue.getCurrencyValue(100d, "SKK")));
+ return Convertor.getConvertorDoubleString(exchangeRates);
+ }
+
+ /** Define convertor that understands three currencies. Use it.
+ */
+ public void testConvertorForUSDandCZKandSKK() throws Exception {
+ Convertor c = createTripleConvertor();
+
+ CurrencyValue result;
+ // convert $5 to CZK using c:
+ // assertEquals("Result is 75 CZK");
+ result = c.convert("CZK", CurrencyValue.getCurrencyValue(5d, "USD"));
+ assertEquals(CurrencyValue.getCurrencyValue(75d, "CZK"), result);
+
+ // convert $5 to SKK using c:
+ // assertEquals("Result is 100 SKK");
+ result = c.convert("SKK", CurrencyValue.getCurrencyValue(5d, "USD"));
+ assertEquals(CurrencyValue.getCurrencyValue(100d, "SKK"), result);
+
+ // convert 200SKK to CZK using c:
+ // assertEquals("Result is 150 CZK");
+ result = c.convert("CZK", CurrencyValue.getCurrencyValue(200d, "SKK"));
+ assertEquals(CurrencyValue.getCurrencyValue(150d, "CZK"), result);
+
+ // convert 200SKK to USK using c:
+ // assertEquals("Result is 10 USD");
+ result = c.convert("USD", CurrencyValue.getCurrencyValue(200d, "SKK"));
+ assertEquals(CurrencyValue.getCurrencyValue(10d, "USD"), result);
+ }
+
+ /** Merge all currency rates of convertor 1 with convertor 2.
+ * Implement this using your API, preferably this method just delegates
+ * into some API method which does the actual work, without requiring
+ * API clients to code anything complex.
+ */
+ public static Convertor merge(Convertor one, Convertor two) {
+ return Convertor.mergeConvertorsDoubleString(one, two);
+ }
+
+ /** Join the convertors from previous task, Task1Test and show that it
+ * can be used to do reasonable conversions.
+ */
+ public void testConvertorComposition() throws Exception {
+ Convertor c = merge(
+ Task1Test.createCZKtoUSD(),
+ Task1Test.createSKKtoCZK());
+
+ CurrencyValue result;
+ // convert $5 to CZK using c:
+ // assertEquals("Result is 85 CZK");
+ result = c.convert("CZK", CurrencyValue.getCurrencyValue(5d, "USD"));
+ assertEquals(CurrencyValue.getCurrencyValue(85d, "CZK"), result);
+
+ // convert $8 to CZK using c:
+ // assertEquals("Result is 136 CZK");
+ result = c.convert("CZK", CurrencyValue.getCurrencyValue(8d, "USD"));
+ assertEquals(CurrencyValue.getCurrencyValue(136d, "CZK"), result);
+
+ // convert 1003CZK to USD using c:
+ // assertEquals("Result is 59 USD");
+ result = c.convert("USD", CurrencyValue.getCurrencyValue(1003d, "CZK"));
+ assertEquals(CurrencyValue.getCurrencyValue(59d, "USD"), result);
+
+ // convert 16CZK using c:
+ // assertEquals("Result is 20 SKK");
+ result = c.convert("SKK", CurrencyValue.getCurrencyValue(16d, "CZK"));
+ assertEquals(CurrencyValue.getCurrencyValue(20d, "SKK"), result);
+
+ // convert 500SKK to CZK using c:
+ // assertEquals("Result is 400 CZK");
+ result = c.convert("CZK", CurrencyValue.getCurrencyValue(500d, "SKK"));
+ assertEquals(CurrencyValue.getCurrencyValue(400d, "CZK"), result);
+ }
+}