japod@6: package org.apidesign.apifest08.test;
japod@6: 
japod@6: import java.util.Currency;
japod@6: import junit.framework.TestCase;
japod@6: import org.apidesign.apifest08.currency.ConversionRate;
japod@6: import org.apidesign.apifest08.currency.Convertor;
japod@6: import org.apidesign.apifest08.currency.MonetaryAmount;
japod@6: import org.apidesign.apifest08.currency.TableConvertor;
japod@6: 
japod@6: /** Finish the Convertor API, and then write bodies of methods inside
japod@6:  * of this class to match the given tasks. To fullfil your task, use the
japod@6:  * API define in the <code>org.apidesign.apifest08.currency</code> package.
japod@6:  * Do not you reflection, or other hacks as your code
japod@6:  * shall run without any runtime permissions.
japod@6:  */
japod@6: public class Task1Test extends TestCase {
japod@6:     public Task1Test(String testName) {
japod@6:         super(testName);
japod@6:     }
japod@6: 
japod@6:     @Override
japod@6:     protected void setUp() throws Exception {
japod@6:     }
japod@6: 
japod@6:     @Override
japod@6:     protected void tearDown() throws Exception {
japod@6:     }
japod@6: 
japod@18:     //
japod@18:     // Imagine that there are three parts of the whole system:
japod@18:     // 1. there is someone who knows the current exchange rate
japod@18:     // 2. there is someone who wants to do the conversion
japod@18:     // 3. there is the API between 1. and 2. which allows them to communicate
japod@18:     // Please design such API
japod@18:     //
japod@18: 
japod@6:     protected static final Currency CZK = Currency.getInstance( "CZK" );
japod@6:     protected static final Currency SKK = Currency.getInstance( "SKK" );
japod@6:     protected static final Currency USD = Currency.getInstance( "USD" );
japod@6:     
japod@6:     /** Create convertor that understands two currencies, CZK and
japod@6:      *  USD. Make 1 USD == 17 CZK.
japod@18:      *  USD. Make 1 USD == 17 CZK. This is a method provided for #1 group -
japod@18:      *  e.g. those that know the exchange rate. They somehow need to create
japod@18:      *  the objects from the API and tell them the exchange rate. The API itself
japod@18:      *  knows nothing about any rates, before the createCZKtoUSD method is called.
japod@6:      *
japod@6:      * Creation of the convertor shall not require subclassing of any class
japod@6:      * or interface on the client side.
japod@6:      *
japod@6:      * @return prepared convertor ready for converting USD to CZK and CZK to USD
japod@6:      */
japod@6:     public static Convertor createCZKtoUSD() {
japod@6:         final TableConvertor convertor = new TableConvertor();
japod@6:         final MonetaryAmount amountInCZK = new MonetaryAmount( 17, CZK );
japod@6:         final MonetaryAmount amountInUSD = new MonetaryAmount( 1, USD );
japod@6:         convertor.putIntoTable( new ConversionRate( amountInCZK, amountInUSD ) );
japod@6:         convertor.putIntoTable( new ConversionRate( amountInUSD, amountInCZK ) );
japod@6:         return new ContractImposingDelegatingConvertor( convertor ).test();
japod@6:     }
japod@6: 
japod@6:     /** Create convertor that understands two currencies, CZK and
japod@18:      *  SKK. Make 100 SKK == 80 CZK. Again this is method for the #1 group -
japod@18:      *  it knows the exchange rate, and needs to use the API to create objects
japod@18:      *  with the exchange rate. Anyone shall be ready to call this method without
japod@18:      *  any other method being called previously. The API itself shall know
japod@18:      *  nothing about any rates, before this method is called.
japod@6:      *
japod@6:      * Creation of the convertor shall not require subclassing of any class
japod@6:      * or interface on the client side.
japod@6:      * 
japod@6:      * @return prepared convertor ready for converting SKK to CZK and CZK to SKK
japod@6:      */
japod@6:     public static Convertor createSKKtoCZK() {
japod@6:         final TableConvertor convertor = new TableConvertor();
japod@6:         final MonetaryAmount amountInSKK = new MonetaryAmount( 100, SKK );
japod@6:         final MonetaryAmount amountInCZK = new MonetaryAmount( 80, CZK );
japod@6:         convertor.putIntoTable( new ConversionRate( amountInSKK, amountInCZK ) );
japod@6:         convertor.putIntoTable( new ConversionRate( amountInCZK, amountInSKK ) );
japod@6:         return new ContractImposingDelegatingConvertor( convertor ).test();
japod@6:     }
japod@6: 
japod@18:     //
japod@18:     // now the methods for group #2 follow:
japod@18:     // this group knows nothing about exchange rates, but knows how to use
japod@18:     // the API to do conversions. It somehow (by calling one of the factory
japod@18:     // methods) gets objects from the API and uses them to do the conversions.
japod@18:     //
japod@18: 
japod@6:     /** Use the convertor from <code>createCZKtoUSD</code> method and do few conversions
japod@6:      * with it.
japod@6:      */
japod@6:     public void testCurrencyCZKUSD() throws Exception {
japod@6:         final Convertor c = createCZKtoUSD();
japod@6:         
japod@6:         // convert $5 to CZK using c:
japod@6:         final Convertor.ConversionResult r1 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 5, USD ), CZK ) );
japod@6:         final MonetaryAmount a1 = r1.getNetAmount();
japod@6:         // assertEquals("Result is 85 CZK");
japod@6:         assertNotNull( a1 );
japod@6:         assertEquals( 85.0, a1.getAmount().doubleValue() );
japod@6:         assertEquals( CZK, a1.getCurrency() );
japod@6: 
japod@6:         // convert $8 to CZK
japod@6:         final Convertor.ConversionResult r2 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 8, USD ), CZK ) );
japod@6:         final MonetaryAmount a2 = r2.getNetAmount();
japod@6:         // assertEquals("Result is 136 CZK");
japod@6:         assertNotNull( a2 );
japod@6:         assertEquals( 136.0, a2.getAmount().doubleValue() );
japod@6:         assertEquals( CZK, a2.getCurrency() );
japod@6: 
japod@6:         // convert 1003CZK to USD
japod@6:         final Convertor.ConversionResult r3 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 1003, CZK ), USD ) );
japod@6:         final MonetaryAmount a3 = r3.getNetAmount();
japod@6:         // assertEquals("Result is 59 USD");
japod@6:         assertNotNull( a3 );
japod@6:         assertEquals( 59.0, a3.getAmount().doubleValue() );
japod@6:         assertEquals( USD, a3.getCurrency() );
japod@6:     }
japod@6: 
japod@6:     /** Use the convertor from <code>createSKKtoCZK</code> method and do few conversions
japod@6:      * with it.
japod@6:      */
japod@6:     public void testCurrencySKKCZK() throws Exception {
japod@6:         final Convertor c = createSKKtoCZK();
japod@6:         
japod@6:         // convert 16CZK using c:
japod@6:         final Convertor.ConversionResult r1 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 16, CZK ), SKK ) );
japod@6:         final MonetaryAmount a1 = r1.getNetAmount();
japod@6:         // assertEquals("Result is 20 SKK");
japod@6:         assertNotNull( a1 );
japod@6:         assertEquals( 20.0, a1.getAmount().doubleValue() );
japod@6:         assertEquals( SKK, a1.getCurrency() );
japod@6:         
japod@6:         // convert 500SKK to CZK
japod@6:         final Convertor.ConversionResult r2 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 500, SKK ), CZK ) );
japod@6:         final MonetaryAmount a2 = r2.getNetAmount();
japod@6:         // assertEquals("Result is 400 CZK");
japod@6:         assertNotNull( a2 );
japod@6:         assertEquals( 400.0, a2.getAmount().doubleValue() );
japod@6:         assertEquals( CZK, a2.getCurrency() );
japod@6:     }
japod@6: 
japod@18:     /** Verify that the CZK to USD convertor knows nothing about SKK.
japod@18:     */
japod@18:     public void testCannotConvertToSKKwithCZKUSDConvertor() throws Exception {
japod@18:         final Convertor c = createCZKtoUSD();
japod@18:         
japod@18:         // convert $5 to SKK, the API shall say this is not possible
japod@18:         final Convertor.ConversionResult r1 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 5, USD ), SKK ) );
japod@18:         final MonetaryAmount a1 = r1.getNetAmount();
japod@18:         assertNull( a1 );
japod@18: 
japod@18:         // convert 500 SKK to CZK, the API shall say this is not possible
japod@18:         final Convertor.ConversionResult r2 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 5, SKK ), CZK ) );
japod@18:         final MonetaryAmount a2 = r2.getNetAmount();
japod@18:         assertNull( a2 );
japod@18:     }
japod@18: 
japod@18:     /** Verify that the CZK to SKK convertor knows nothing about USD.
japod@18:     */
japod@18:     public void testCannotConvertToUSDwithCZKSKKConvertor() throws Exception {
japod@18:         final Convertor c = createSKKtoCZK();
japod@18:         
japod@18:         // convert $5 to SKK, the API shall say this is not possible
japod@18:         final Convertor.ConversionResult r1 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 5, USD ), SKK ) );
japod@18:         final MonetaryAmount a1 = r1.getNetAmount();
japod@18:         assertNull( a1 );
japod@18:         
japod@18:         // convert 500 CZK to USD, the API shall say this is not possible
japod@18:         final Convertor.ConversionResult r2 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 5, CZK ), USD ) );
japod@18:         final MonetaryAmount a2 = r2.getNetAmount();
japod@18:         assertNull( a2 );
japod@18:     }
japod@18: 
japod@6: }
japod@6: