false if From->To is not supported.
+ * Set to true if both ways From->To and To->From conversions are not supported.
+ *
+ */
+ public ConversionNotSupportedException(String from, String to, boolean twoWay) {
+ this.from = from;
+ this.to = to;
+ this.reversed = true;
+ }
+
+ @Override
+ public String toString() {
+ if (from!=null && to !=null) {
+ if (reversed) {
+ return "Neither onversion nor reverted conversion from " + from + " to " + to + " is not supported,";
+ } else {
+ return "Conversion from " + from + " to " + to + " is not supported,";
+ }
+ } else {
+ return super.toString();
+ }
+ }
+
+ /**
+ * Returns code of source currency. This value may be null.
+ * @return Returns code of source currency.
+ */
+ public String getFromCurrecyCode() {
+ return from;
+ }
+
+ /**
+ * Returns code of target currency. This value may be null.
+ * @return Returns code of target currency.
+ */ public String getToCurrecyCode() {
+ return to;
+ }
+
+ /**
+ * Returns if one way of two way conversion is not supported.
+ *
+ * Value false means one way conversion is not supported. Value true means
+ * that two way conversio is not supported.
+ *
+ * @return Returs false for one way conversion, true for two way conversion.
+ */
+ public boolean getTwoWayConversion() {
+ return reversed;
+ }
+
+}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/src/org/apidesign/apifest08/currency/ConversionResult.java
--- a/task2/solution13/src/org/apidesign/apifest08/currency/ConversionResult.java Tue Oct 07 00:47:25 2008 +0200
+++ b/task2/solution13/src/org/apidesign/apifest08/currency/ConversionResult.java Tue Oct 07 01:18:23 2008 +0200
@@ -6,8 +6,8 @@
/**
* Result of currency conversion. Holds converted value and remainder.
* - * Converter describes value converted to target value. Remainder describes - * how much from original amount was not possible to convert. Converted never loses any (small) money + * Converted describes value converted to target currenty. Remainder describes + * how much from original amount was not possible to convert. Convertor never loses any (small) money * in conversion error (rounding), but instead of rounding is converts only as much as possible and keeps rest as remainder. * * @author arnostvalicek diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/src/org/apidesign/apifest08/currency/Convertor.java --- a/task2/solution13/src/org/apidesign/apifest08/currency/Convertor.java Tue Oct 07 00:47:25 2008 +0200 +++ b/task2/solution13/src/org/apidesign/apifest08/currency/Convertor.java Tue Oct 07 01:18:23 2008 +0200 @@ -5,23 +5,54 @@ import java.math.RoundingMode; /** Convertor able to convert amount from one currency to other currency. + *
+ * Conversion method are: + *
Convertor as merge of provided convertors. Merged convertor will use
+ * provided convertors to convert between currencies.
+ *
+ * Only one should be able to provide conversion between currencies. If more than one convertos
+ * are able to convert currency, one of conversions will be used (it is not defined which).
+ *
+ * @since version 2
+ * @param convertors Convertor used to create merge-convertor.
+ * @return Returns new convertor instance.
+ */
+ public static Convertor createConvertorAsMerge(Convertor[] convertors) {
+ return new Convertor(convertors);
+ }
+
+ boolean remainderAllowed = true; //if false, remained is not allowed (should be true ideally, but can't handle it now)
ExchangeRateProvider exchangeRateProvider;
+ /** Create simle convertor.
+ */
private Convertor() {
-
+ this.convertors=new Convertor[0];
+ }
+
+ /** Create merge convertor.
+ */
+ private Convertor(Convertor[] convertors) {
+ this.convertors = convertors;
}
/**
- * Static method used to create convertor.
+ * Create new
+ * Exchange rate is provided by exchange rate provider which was specified when Convertor was created.
+ * This method is using only exchange rate from->to and not trying to use reverted excange rate to->from.
+ *
+ * @param fromCurrency Source currency to convert from.
+ * @param toCurrency Target currency to convert to.
+ * @param value Value in source currency which should be converted.
+ * @return Return conversion result.
+ * @since version2
+ * @throws ConversionNotSupportedException If conversion from
+ * This method is using only exchange rate from->to and if not found, it is trying to use reverted excange rate to->from.
+ *
+ * @param fromCurrency Source currency to convert from.
+ * @param toCurrency Target currency to convert to.
+ * @param value Value in source currency which should be converted.
+ * @return Return conversion result.
+ * @since version2
+ * @throws ConversionNotSupportedException If conversion from
+ * Provided exchange rate is not chaged, this method returns different instance describing reverted exchange rate.
+ *
+ * @param rate Exchange rate which describes rate to be reverted.
+ * @return Instance of reverted rate.
+ */
+ public static ExchangeRate createRevertedRate(ExchangeRate rate) {
+ ExchangeRate reverted = new ExchangeRate(rate.getToValue(), rate.getFromValue());
+ return reverted;
+ }
@Override
public String toString() {
return "for "+numberFor+" recieve "+numberGet+" @"+getClass().getName();
}
+ /**
+ * Return exchange rate from value stored in this object.
+ * @return Returns from value for this exchange rate.
+ */
public BigDecimal getFromValue() {
return numberFor;
}
+ /**
+ * Return exchange rate to value stored in this object.
+ * @return Returns to value for this exchange rate.
+ */
public BigDecimal getToValue() {
return numberGet;
}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/src/org/apidesign/apifest08/currency/ExchangeRateProvider.java
--- a/task2/solution13/src/org/apidesign/apifest08/currency/ExchangeRateProvider.java Tue Oct 07 00:47:25 2008 +0200
+++ b/task2/solution13/src/org/apidesign/apifest08/currency/ExchangeRateProvider.java Tue Oct 07 01:18:23 2008 +0200
@@ -3,27 +3,33 @@
import java.math.BigDecimal;
import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
/**
- * Exchange rate provider - can provide fixed exchange rate which does not depend
- * on date (method {@link #getExchangeRate()} ) or exchange rate based on date (method {@link #getExchangeRate(java.util.Date) }).
+ * Exchange rate provider. Provides fixed exchange rate which does not depend
+ * on date (method {@link #getExchangeRate()} ).
*
+ * Date dependend exchange rate to be implemented.
*
* @author arnostvalicek
*/
public class ExchangeRateProvider {
BigDecimal fromValue, toValue;
ConvertorCurrency fromCurrency, toCurrency;
+
+ Map exchangeRateMap = new HashMap();
/**
* Simple constructor for
+ * Example of specifiing conversion rate: 100 SKK == 80 CZK:
+ *
+ * @param fromCurrency Source currency.
+ * @param fromValue Valye for from currency.
+ * @param toCurrency Target currency.
+ * @param toValue Value for target currency.
+ */
+ public synchronized void addFixedCurencyRate(ConvertorCurrency fromCurrency, BigDecimal fromValue, ConvertorCurrency toCurrency, BigDecimal toValue) {
+ if (fromValue==null) {
+ throw new NullPointerException("fromValue can't be null");
+ }
+ if (toValue==null) {
+ throw new NullPointerException("toValue can't be null");
+ }
+ Map map2 = (Map) exchangeRateMap.get(fromCurrency);
+ if (map2==null) {
+ map2 = new HashMap();
+ exchangeRateMap.put(fromCurrency, map2);
+ }
+
+ ExchangeRate rate = new ExchangeRate(fromValue, toValue);
+ map2.put(toCurrency, rate);
+ }
+
/**
* Get fixed exange rate for currencies (from->to).
* @return Returns exchange rate.
+ * @deprecated deprecated since task2. Use {@link #getExchangeRate(ConvertorCurrency, ConvertorCurrency) }
*/
public ExchangeRate getExchangeRate() {
return new ExchangeRate(fromValue, toValue);
}
+
+
+ /**
+ * Get fixed exange rate for currencies (from->to).
+ * @return Returns exchange rate or
+ * 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 {
+ private static ConvertorCurrency currencyCZK = ConvertorCurrency.getInstance("CZK");
+ private static ConvertorCurrency currencySKK = ConvertorCurrency.getInstance("SKK");
+ private static ConvertorCurrency currencyUSD = ConvertorCurrency.getInstance("USD");
+
+ public Task2Test(String testName) {
+ super(testName);
+ }
+
+ @Override
+ protected void setUp() throws Exception {
+
+ }
+
+ @Override
+ protected void tearDown() throws Exception {
+ }
+
+ public static Convertor createUsdToSkkConvertor() {
+ ConvertorCurrency fromCurrency = currencyUSD;
+ ConvertorCurrency toCurrency = currencyUSD;
+ ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(1), fromCurrency, new BigDecimal(20), toCurrency);
+
+ return Convertor.createConvertor(exchangeRateProvider);
+
+ }
+
+ // 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() {
+ ExchangeRateProvider exRateProvider = ExchangeRateProvider.createExchangeRateProvider();
+
+ // Rates: 1USD = 15CZK
+ exRateProvider.addFixedCurencyRate(currencyUSD, new BigDecimal(1),currencyCZK, new BigDecimal(15));
+
+ // Rates: 1USD = 20SKK
+ exRateProvider.addFixedCurencyRate(currencyUSD, new BigDecimal(1), currencySKK, new BigDecimal(20));
+
+ // Rates: 75CZK = 100SKK
+ exRateProvider.addFixedCurencyRate(currencyCZK, new BigDecimal(75), currencySKK, new BigDecimal(100));
+
+ Convertor c = Convertor.createConvertor(exRateProvider);
+
+ return c;
+ }
+
+ /** Define convertor that understands three currencies. Use it.
+ */
+ public void testConvertorForUSDandCZKandSKK() throws Exception {
+ Convertor c = createTripleConvertor();
+
+ // convert $5 to CZK using c:
+ assertEquals("Result is 75 CZK",new BigDecimal("75.00"),c.convertWithReversibleRates(currencyUSD, currencyCZK, new BigDecimal(5)).getConverted());
+
+
+ // convert $5 to SKK using c:
+ assertEquals("Result is 100 SKK",new BigDecimal("100.00"),c.convertWithReversibleRates(currencyUSD, currencySKK, new BigDecimal(5)).getConverted());
+
+ // convert 200SKK to CZK using c:
+ assertEquals("Result is 150 CZK",new BigDecimal("150.00"),c.convertWithReversibleRates(currencySKK, currencyCZK, new BigDecimal(200)).getConverted());
+
+ // convert 200SKK to USK using c:
+ // assertEquals("Result is 10 USD");
+ }
+
+ /** 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.createConvertorAsMerge(new Convertor[]{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()
+ );
+
+ // convert $5 to CZK using c:
+ assertEquals("Result is 85 CZK",new BigDecimal("85.00"),c.convertWithReversibleRates(currencyUSD, currencyCZK, new BigDecimal(5)).getConverted());
+
+ // convert $8 to CZK using c:
+ // assertEquals("Result is 136 CZK");
+ assertEquals("Result is 136 CZK",new BigDecimal("136.00"),c.convertWithReversibleRates(currencyUSD, currencyCZK, new BigDecimal(8)).getConverted());
+
+ // convert 1003CZK to USD using c:
+ assertEquals("Result is 59 USD",new BigDecimal("59.00"),c.convertWithReversibleRates(currencyCZK, currencyUSD, new BigDecimal(1003)).getConverted());
+
+ // convert 16CZK using c:
+ assertEquals("Result is 20 SKK",new BigDecimal("20.00"),c.convertWithReversibleRates(currencyCZK, currencySKK, new BigDecimal(16)).getConverted());
+
+ // convert 500SKK to CZK using c:
+ assertEquals("Result is 400 CZK",new BigDecimal("400.00"),c.convertWithReversibleRates(currencySKK, currencyCZK, new BigDecimal(500)).getConverted());
+
+ }
+}
Convertor using ExchangeRateProvider.
*
* @param exchangeRateProvider {@link ExchangeRateProvider} used to get exchange rate.
*
* @return Returns Convertor which can be used to convert money.
+ * @since version1
*/
public static Convertor createConvertor(ExchangeRateProvider exchangeRateProvider) {
Convertor c = new Convertor();
@@ -36,9 +67,11 @@
*
* @param amount Amount which should be converted. Can't be negative value (can be zero or positive).
* @return Return ConversionResult which holds conversion result.
+ * @since version1
+ * @deprecated since version2. Use {@link #convert(ConvertorCurrency, ConvertorCurrency, BigDecimal) } - explicitly specify conversion currencies.
*/
public ConversionResult convert(BigDecimal amount) {
- return convertValue(amount, false);
+ return convertValue(exchangeRateProvider.getFromCurrency(), exchangeRateProvider.getToCurrency(),amount, false,false);
}
/**
@@ -47,32 +80,44 @@
*
* @param amount Amount which should be converted. Can't be negative value (can be zero or positive).
* @return Return ConversionResult which holds conversion result.
+ * @since version1
+ * @deprecated since version2. Use {@link #convert(ConvertorCurrency, ConvertorCurrency, BigDecimal) } - explicitly specify conversion currencies.
*/
public ConversionResult convertBack(BigDecimal amount) {
- return convertValue(amount, true);
+ return convertValue(exchangeRateProvider.getFromCurrency(), exchangeRateProvider.getToCurrency(),amount, true,false);
}
- private ConversionResult convertValue(BigDecimal amount, boolean convertBack) throws RuntimeException {
+ private ConversionResult convertUsingSimpleConvertor(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency, boolean reversibleExRate, BigDecimal amount, boolean convertBack) throws ConversionNotSupportedException, RuntimeException {
ConversionResult result = new ConversionResult();
-
- ExchangeRate rate = exchangeRateProvider.getExchangeRate();
- int fromFranctionDigits = exchangeRateProvider.getFromCurrency().getDefaultFractionDigits();
- int toFractionDigits = exchangeRateProvider.getToCurrency().getDefaultFractionDigits();
-
- if (toFractionDigits!=2) {
- throw new RuntimeException("Can't process currency with defaultFractionDigits!=2, "+exchangeRateProvider.getToCurrency()+" has "+toFractionDigits+" defaultFractionDigits");
+
+ //ExchangeRate rate = exchangeRateProvider.getExchangeRate();
+ ExchangeRate rate;
+ if (reversibleExRate) {
+ rate = exchangeRateProvider.getReversibleExchangeRate(fromCurrency, toCurrency);
+ } else {
+ rate = exchangeRateProvider.getExchangeRate(fromCurrency, toCurrency);
}
- if (fromFranctionDigits!=2) {
- throw new RuntimeException("Can't process currency with defaultFractionDigits!=2, "+exchangeRateProvider.getFromCurrency()+" has "+fromFranctionDigits+" defaultFractionDigits");
+ if (rate == null) {
+ return null;
}
- if (amount.signum()==-1) {
- throw new RuntimeException("Can convert only non-negative value, current value is "+amount);
+ int fromFranctionDigits = fromCurrency.getDefaultFractionDigits();
+ int toFractionDigits = toCurrency.getDefaultFractionDigits();
+
+ if (toFractionDigits != 2) {
+ throw new ConvertorException("Can't process currency with defaultFractionDigits!=2, " + exchangeRateProvider.getToCurrency() + " has " + toFractionDigits + " defaultFractionDigits");
}
-
-
+ if (fromFranctionDigits != 2) {
+ throw new ConvertorException("Can't process currency with defaultFractionDigits!=2, " + exchangeRateProvider.getFromCurrency() + " has " + fromFranctionDigits + " defaultFractionDigits");
+ }
+
+ if (amount.signum() == -1) {
+ throw new RuntimeException("Can convert only non-negative value, current value is " + amount);
+ }
+
+
MathContext context = new MathContext(0, RoundingMode.DOWN);
-
+
BigDecimal from;
BigDecimal to;
if (convertBack) {
@@ -80,26 +125,89 @@
to = rate.getFromValue();
from = rate.getToValue();
} else {
- //converting in mornak way
+ //converting in normal way
from = rate.getFromValue();
to = rate.getToValue();
}
BigDecimal amountCent = amount.movePointRight(2);
-
- final BigDecimal multiplied = amountCent.multiply(to,context);
- BigDecimal[] division = multiplied.divideAndRemainder(from,context);
+
+ final BigDecimal multiplied = amountCent.multiply(to, context);
+ BigDecimal[] division = multiplied.divideAndRemainder(from, context);
if (!remainderAllowed && !(BigDecimal.ZERO.equals(division[1]))) {
- throw new RuntimeException("Remained is not allowed - remaining amount is " + division[1]+ " cents");
+ throw new RuntimeException("Remained is not allowed - remaining amount is " + division[1] + " cents");
} else {
result.setRemainder(BigDecimal.ZERO);
}
-
- final BigDecimal converted = division[0].movePointLeft(2);
+
+ final BigDecimal converted = division[0].movePointLeft(2);
result.setConverted(converted);
//result.setRemainder(...);
-
return result;
}
+
+
+ private ConversionResult convertValue(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency,BigDecimal amount, boolean convertBack,boolean reversibleExRate) throws RuntimeException {
+ //result.setRemainder(...);
+ if (convertors.length==0) {
+ return convertUsingSimpleConvertor(fromCurrency, toCurrency, reversibleExRate, amount, convertBack);
+ } else {
+ ConversionResult result = null;
+ for (int i = 0;ifromCurrency to toCurrency.
+ * fromCurrency to toCurrency is not supported.
+ */
+ public ConversionResult convert(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency, BigDecimal value) {
+ ConversionResult result = convertValue(fromCurrency, toCurrency, value, false,false);
+ if (result==null) {
+ //throw new ConversionNotSupportedException("Conversion from " + fromCurrency + " to " + toCurrency + " is not supported");
+ throw new ConversionNotSupportedException(fromCurrency.getCurrencyCode(),toCurrency.getCurrencyCode(),false);
+ }
+ return result;
+ }
+
+ /**
+ * Convert value from fromCurrency to toCurrency.
+ * Exchange rate is provided by exchange rate provider which was specified when Convertor was created.
+ * fromCurrency to toCurrency
+ * is not supported and neither conversion from toCurrency to fromCurrency is not supported.
+ */
+ public ConversionResult convertWithReversibleRates(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency, BigDecimal value) {
+ ConversionResult result = convertValue(fromCurrency, toCurrency, value, false,true);
+ if (result==null) {
+ //throw new ConversionNotSupportedException("Neither onversion nor reverted conversion from " + fromCurrency + " to " + toCurrency + " is not supported,");
+ throw new ConversionNotSupportedException(fromCurrency.getCurrencyCode(),toCurrency.getCurrencyCode(),true);
+ }
+ return result;
+ }
+
}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/src/org/apidesign/apifest08/currency/ConvertorCurrency.java
--- a/task2/solution13/src/org/apidesign/apifest08/currency/ConvertorCurrency.java Tue Oct 07 00:47:25 2008 +0200
+++ b/task2/solution13/src/org/apidesign/apifest08/currency/ConvertorCurrency.java Tue Oct 07 01:18:23 2008 +0200
@@ -40,7 +40,24 @@
}
@Override
+ public boolean equals(Object obj) {
+ boolean result;
+ if (obj instanceof ConvertorCurrency) {
+ ConvertorCurrency that = (ConvertorCurrency) obj;
+ result = currency.equals(that.currency);
+ } else {
+ result = false;
+ }
+ return result;
+ }
+
+
+ @Override
public String toString() {
- return getClass() + " based on " + (currency != null ? currency.toString() : "NO-BASE-CURRENCY");
+ return "ConvertorCurrency[" + (currency != null ? currency.toString() : "NO-BASE-CURRENCY")+"]";
+ }
+
+ String getCurrencyCode() {
+ return currency.getCurrencyCode();
}
}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/src/org/apidesign/apifest08/currency/ConvertorException.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/task2/solution13/src/org/apidesign/apifest08/currency/ConvertorException.java Tue Oct 07 01:18:23 2008 +0200
@@ -0,0 +1,25 @@
+package org.apidesign.apifest08.currency;
+
+/**
+ * Common Convertor exception.
+ *
+ * @author arnostvalicek
+ */
+public class ConvertorException extends RuntimeException {
+
+ public ConvertorException(Throwable cause) {
+ super(cause);
+ }
+
+ public ConvertorException(String message, Throwable cause) {
+ super(message, cause);
+ }
+
+ public ConvertorException(String message) {
+ super(message);
+ }
+
+ public ConvertorException() {
+ }
+
+}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/src/org/apidesign/apifest08/currency/ExchangeRate.java
--- a/task2/solution13/src/org/apidesign/apifest08/currency/ExchangeRate.java Tue Oct 07 00:47:25 2008 +0200
+++ b/task2/solution13/src/org/apidesign/apifest08/currency/ExchangeRate.java Tue Oct 07 01:18:23 2008 +0200
@@ -12,20 +12,47 @@
private BigDecimal numberFor;
private BigDecimal numberGet;
+ /**
+ * Constructor for new exchange rate holding two values - from value and to value
+ * @param fromValue Exchange rate from value
+ * @param toValue Exchange rate to value
+ */
public ExchangeRate(BigDecimal fromValue, BigDecimal toValue) {
this.numberFor = fromValue;
this.numberGet = toValue;
}
+
+ /**
+ * Create new instance of ExchangeRate based on provided exchange rate, but swapping its
+ * from and to value.
+ * ExchangeRateProviderM which can provide fixed exchange rate.
*
- * Describes conversion from to to currency.
+ * Describes conversion from ONE to to ONE currency.
*
* @param fromValue From value. BigDecimal value, precision should be set to currency precision.
* @param fromCurrency From currency.
* @param toValue To value. BigDecimal value, precision should be set to currency precision.
* @param toCurrency To currency.
+ * @deprecated deprecated since task2. Use {@link #createExchangeRateProvider() } instead of this constructor.
*/
public ExchangeRateProvider(BigDecimal fromValue, ConvertorCurrency fromCurrency, BigDecimal toValue, ConvertorCurrency toCurrency) {
this.fromValue = fromValue;
@@ -32,18 +38,89 @@
this.toCurrency = toCurrency;
}
+ private ExchangeRateProvider() {
+
+ }
+
+ /**
+ * Static method to create new exchange rate provider. This exchange rate provider does not contain
+ * any exchange rates (this is difference to public constructor).
+ * @return New ExchangeRateProvider
+ */
+ public static ExchangeRateProvider createExchangeRateProvider() {
+ ExchangeRateProvider provider = new ExchangeRateProvider();
+ return provider;
+ }
+
+ /**
+ * Add new exchange rate to to this exchange rate provider.
+ *
+ * addFixedCurencyRate(ConvertorCurrency.getInstance("SKK"), new BigDecimal(100), ConvertorCurrency.getInstance("CZK"), new BigDecimal(80));
+ * null if exchange rate not found.
+ */
+ public ExchangeRate getExchangeRate(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency) {
+ return getExchangeRateImpl(fromCurrency, toCurrency);
+ }
+
+ /**
+ * Get fixed exange rate for currencies (from->to) or reversed exchange rate (to->from).
+ * @return Returns exchange rate or null if exchange rate not found.
+ */
+ public ExchangeRate getReversibleExchangeRate(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency) {
+ ExchangeRate rate = getExchangeRateImpl(fromCurrency, toCurrency);
+ if (rate==null) {
+ ExchangeRate revertedRate = getExchangeRateImpl(toCurrency, fromCurrency);
+ if (revertedRate!=null) {
+ rate = ExchangeRate.createRevertedRate(revertedRate);
+ }
+ }
+ return rate;
+ }
+
+
/**
* Get exchange rate for currencies (from->to) based on provided date.
* @param date Date for which exchange rate should be provided.
* @return Returns exchange rate
+ * @deprecated deprecated since task2. No real implementation in version2.
*/
public ExchangeRate getExchangeRate(Date date) {
return new ExchangeRate(fromValue, toValue);
@@ -57,6 +134,19 @@
ConvertorCurrency getToCurrency() {
return toCurrency;
}
+
+ private ExchangeRate getExchangeRateImpl(ConvertorCurrency fromCurrency, ConvertorCurrency toCurrency) {
+ if (fromValue != null && toValue != null && fromCurrency.equals(this.fromCurrency) && toCurrency.equals(this.toCurrency)) {
+ return new ExchangeRate(fromValue, toValue);
+ }
+ //return new ExchangeRate(fromValue, toValue);
+ Map map2 = (Map) exchangeRateMap.get(fromCurrency);
+ if (map2 == null) {
+ return null;
+ }
+ ExchangeRate result = (ExchangeRate) map2.get(toCurrency);
+ return result;
+ }
}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/test/org/apidesign/apifest08/test/Task1Test.java
--- a/task2/solution13/test/org/apidesign/apifest08/test/Task1Test.java Tue Oct 07 00:47:25 2008 +0200
+++ b/task2/solution13/test/org/apidesign/apifest08/test/Task1Test.java Tue Oct 07 01:18:23 2008 +0200
@@ -6,6 +6,7 @@
import org.apidesign.apifest08.currency.Convertor;
import org.apidesign.apifest08.currency.ConvertorCurrency;
import org.apidesign.apifest08.currency.ExchangeRateProvider;
+import org.apidesign.apifest08.currency.ConversionNotSupportedException;
/** Finish the Convertor API, and then write bodies of methods inside
* of this class to match the given tasks. To fullfil your task, use the
@@ -34,7 +35,7 @@
*
* @return prepared convertor ready for converting USD to CZK and CZK to USD
*/
- public Convertor createCZKtoUSD() {
+ public static Convertor createCZKtoUSD() {
ConvertorCurrency fromCurrency = ConvertorCurrency.getInstance("CZK");
ConvertorCurrency toCurrency = ConvertorCurrency.getInstance("USD");
ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(17), fromCurrency, new BigDecimal(1), toCurrency);
@@ -50,7 +51,7 @@
*
* @return prepared convertor ready for converting SKK to CZK and CZK to SKK
*/
- public Convertor createSKKtoCZK() {
+ public static Convertor createSKKtoCZK() {
ConvertorCurrency fromCurrency = ConvertorCurrency.getInstance("SKK");
ConvertorCurrency toCurrency = ConvertorCurrency.getInstance("CZK");
ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(100), fromCurrency, new BigDecimal(80), toCurrency);
@@ -59,7 +60,7 @@
}
- public Convertor createCZKtoYEN() {
+ public static Convertor createCZKtoYEN() {
ConvertorCurrency fromCurrency = ConvertorCurrency.getInstance("CZK");
ConvertorCurrency toCurrency = ConvertorCurrency.getInstance("JPY");
ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(1), fromCurrency, new BigDecimal(1), toCurrency);
@@ -200,8 +201,21 @@
public void testCannotConvertToSKKwithCZKUSDConvertor() throws Exception {
Convertor c = createCZKtoUSD();
// convert $5 to SKK, the API shall say this is not possible
+ try {
+ c.convert(ConvertorCurrency.getInstance("USD"), ConvertorCurrency.getInstance("SKK"), new BigDecimal(5));
+ fail();
+ } catch (ConversionNotSupportedException e) {
+ //expected error;
+ assertEquals("Exception From USD", "USD",e.getFromCurrecyCode());
+ assertEquals("Exception To SKK", "SKK",e.getToCurrecyCode());
+ }
// convert 500 SKK to CZK, the API shall say this is not possible
- // ... no api for required call, should be here?
+ try {
+ c.convert(ConvertorCurrency.getInstance("SKK"), ConvertorCurrency.getInstance("CZK"), new BigDecimal(500));
+ fail();
+ } catch (ConversionNotSupportedException e) {
+ assertEquals("Exception From USD", "SKK",e.getFromCurrecyCode());
+ assertEquals("Exception To SKK", "CZK",e.getToCurrecyCode()); }
}
diff -r e6cd39d9b6a2 -r a7e6f84fb078 task2/solution13/test/org/apidesign/apifest08/test/Task2Test.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/task2/solution13/test/org/apidesign/apifest08/test/Task2Test.java Tue Oct 07 01:18:23 2008 +0200
@@ -0,0 +1,136 @@
+package org.apidesign.apifest08.test;
+
+import java.math.BigDecimal;
+import junit.framework.TestCase;
+import org.apidesign.apifest08.currency.Convertor;
+import org.apidesign.apifest08.currency.ConvertorCurrency;
+import org.apidesign.apifest08.currency.ExchangeRateProvider;
+
+/** 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.
+ *