1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/task3/solution07/src/org/apidesign/apifest08/currency/anothervendor/ZigZaggingBidirectionalConvertor.java Fri Oct 10 22:10:25 2008 +0200
1.3 @@ -0,0 +1,130 @@
1.4 +/*
1.5 + * To change this template, choose Tools | Templates
1.6 + * and open the template in the editor.
1.7 + */
1.8 +
1.9 +package org.apidesign.apifest08.currency.anothervendor;
1.10 +
1.11 +import java.math.BigDecimal;
1.12 +import java.util.Currency;
1.13 +import java.util.Iterator;
1.14 +import org.apidesign.apifest08.currency.Convertor;
1.15 +import org.apidesign.apifest08.currency.IllegalRequestSubtypeException;
1.16 +import org.apidesign.apifest08.currency.MonetaryAmount;
1.17 +
1.18 +
1.19 +/**
1.20 + * A convertor that changes the rate by a step amount on every conversion it performs.
1.21 + * @author jdvorak
1.22 + */
1.23 +public class ZigZaggingBidirectionalConvertor implements Convertor {
1.24 +
1.25 + private final MonetaryAmount srcRateAmount;
1.26 +
1.27 + private final Currency tgtCurrency;
1.28 +
1.29 + private final Iterator<BigDecimal> rateIterator;
1.30 +
1.31 + /**
1.32 + * Costructor with the precise amounts.
1.33 + * @param srcRateAmount
1.34 + * @param tgtCurrency
1.35 + * @param startAmount
1.36 + * @param endAmount
1.37 + * @param stepAmount
1.38 + */
1.39 + public ZigZaggingBidirectionalConvertor( final MonetaryAmount srcRateAmount, final Currency tgtCurrency, final BigDecimal startAmount, final BigDecimal endAmount, final BigDecimal stepAmount ) {
1.40 + this.srcRateAmount = srcRateAmount;
1.41 + this.tgtCurrency = tgtCurrency;
1.42 + this.rateIterator = new ZigZaggingBigDecimalIterator( startAmount, endAmount, stepAmount );
1.43 + }
1.44 +
1.45 + /**
1.46 + * Do the conversion; updates the rate.
1.47 + * @param req
1.48 + * @return
1.49 + * @throws org.apidesign.apifest08.currency.IllegalRequestSubtypeException
1.50 + */
1.51 + public synchronized ConversionResult convert( ConversionRequest req ) throws IllegalRequestSubtypeException {
1.52 + if ( tgtCurrency.equals( req.getTgtCurrency() ) ) {
1.53 + if ( srcRateAmount.getCurrency().equals( req.getSrcAmount().getCurrency() ) ) {
1.54 + final BigDecimal tgtRateAmount = rateIterator.next();
1.55 + final BigDecimal tgtAmount = req.getSrcAmount().getAmount().multiply( tgtRateAmount ).divide( srcRateAmount.getAmount() );
1.56 + return new ConversionResult( new MonetaryAmount( tgtAmount, tgtCurrency ) );
1.57 + }
1.58 + }
1.59 + if ( srcRateAmount.getCurrency().equals( req.getTgtCurrency() ) ) {
1.60 + if ( tgtCurrency.equals( req.getSrcAmount().getCurrency() ) ) {
1.61 + final BigDecimal tgtRateAmount = rateIterator.next();
1.62 + final BigDecimal tgtAmount = req.getSrcAmount().getAmount().multiply( srcRateAmount.getAmount() ).divide( tgtRateAmount );
1.63 + return new ConversionResult( new MonetaryAmount( tgtAmount, srcRateAmount.getCurrency() ) );
1.64 + }
1.65 + }
1.66 + return new ConversionResult( null );
1.67 + }
1.68 +
1.69 +}
1.70 +
1.71 +/**
1.72 + * An iterator that goes zig first, then zag, then zig again, then zag again, ad libitum.
1.73 + * @author jdvorak
1.74 + */
1.75 +class ZigZaggingBigDecimalIterator implements Iterator<BigDecimal> {
1.76 +
1.77 + private BigDecimal zigBounce;
1.78 +
1.79 + private BigDecimal zagBounce;
1.80 +
1.81 + private BigDecimal step;
1.82 +
1.83 + private BigDecimal currentValue;
1.84 +
1.85 + protected ZigZaggingBigDecimalIterator( final BigDecimal zagBounce, final BigDecimal zigBounce, final BigDecimal step ) {
1.86 + this. zigBounce = zigBounce;
1.87 + this.zagBounce = zagBounce;
1.88 + this.currentValue = zagBounce;
1.89 + this.step = step;
1.90 +
1.91 + if ( zigBounce == null ) {
1.92 + throw new NullPointerException( "zigAmount" );
1.93 + }
1.94 + if ( zagBounce == null ) {
1.95 + throw new NullPointerException( "zagAmount" );
1.96 + }
1.97 + if ( step == null ) {
1.98 + throw new NullPointerException( "stepAmount" );
1.99 + }
1.100 + final int stepSign = step.signum();
1.101 + if ( stepSign == 0 ) {
1.102 + throw new IllegalArgumentException( "stepAmount can't be zero" );
1.103 + }
1.104 + if ( stepSign * zigBounce.compareTo( zagBounce ) < 0 ) {
1.105 + throw new IllegalArgumentException( "stepAmount shall have the same sign as endAmount - startAmount" );
1.106 + }
1.107 + }
1.108 +
1.109 + public boolean hasNext() {
1.110 + return true;
1.111 + }
1.112 +
1.113 + public BigDecimal next() {
1.114 + final BigDecimal result = currentValue;
1.115 +
1.116 + currentValue = currentValue.add( step );
1.117 + final int stepSign = step.signum();
1.118 + final int currentMinusZigSign = currentValue.compareTo( zigBounce );
1.119 + if ( stepSign * currentMinusZigSign >= 0 ) {
1.120 + final BigDecimal temp = zigBounce;
1.121 + zigBounce = zagBounce;
1.122 + zagBounce = temp;
1.123 + step = step.negate();
1.124 + }
1.125 +
1.126 + return result;
1.127 + }
1.128 +
1.129 + public void remove() {
1.130 + throw new UnsupportedOperationException("Removal is not supported.");
1.131 + }
1.132 +
1.133 +}
1.134 \ No newline at end of file
2.1 --- a/task3/solution07/test/org/apidesign/apifest08/test/Task3Test.java Fri Oct 10 22:07:25 2008 +0200
2.2 +++ b/task3/solution07/test/org/apidesign/apifest08/test/Task3Test.java Fri Oct 10 22:10:25 2008 +0200
2.3 @@ -1,7 +1,11 @@
2.4 package org.apidesign.apifest08.test;
2.5
2.6 +import java.math.BigDecimal;
2.7 +import java.util.Currency;
2.8 import junit.framework.TestCase;
2.9 import org.apidesign.apifest08.currency.Convertor;
2.10 +import org.apidesign.apifest08.currency.MonetaryAmount;
2.11 +import org.apidesign.apifest08.currency.anothervendor.ZigZaggingBidirectionalConvertor;
2.12
2.13 /** The exchange rates are not always the same. They are changing. Day by day,
2.14 * hour by hour, minute by minute. For every bank it is important to always
2.15 @@ -28,6 +32,10 @@
2.16 protected void tearDown() throws Exception {
2.17 }
2.18
2.19 + protected static final Currency CZK = Currency.getInstance( "CZK" );
2.20 + protected static final Currency SKK = Currency.getInstance( "SKK" );
2.21 + protected static final Currency USD = Currency.getInstance( "USD" );
2.22 +
2.23 // Backward compatibly enhance your existing API to support following
2.24 // usecases:
2.25 //
2.26 @@ -51,7 +59,11 @@
2.27 // then 1USD = 15.02CZK
2.28 // and so on and on up to 1USD = 16CZK
2.29 // and then another round to 15, etc.
2.30 - return null;
2.31 + final MonetaryAmount oneUSD = new MonetaryAmount( 1, USD );
2.32 + final BigDecimal startAmount = new BigDecimal( 16 );
2.33 + final BigDecimal endAmount = new BigDecimal( 15 );
2.34 + final BigDecimal stepAmount = BigDecimal.ONE.movePointLeft( 2 ).negate();
2.35 + return new ContractImposingDelegatingConvertor( new ZigZaggingBidirectionalConvertor( oneUSD, CZK, startAmount, endAmount, stepAmount ) );
2.36 }
2.37
2.38 public void testFewQueriesForOnlineConvertor() {
2.39 @@ -64,20 +76,39 @@
2.40 doFewQueriesForOnlineConvertor(c);
2.41 }
2.42
2.43 - static void doFewQueriesForOnlineConvertor(Convertor c) {
2.44 + static void doFewQueriesForOnlineConvertor( final Convertor c ) {
2.45 // convert $5 to CZK using c:
2.46 + final Convertor.ConversionResult r1 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 5, USD ), CZK ) );
2.47 + final MonetaryAmount a1 = r1.getNetAmount();
2.48 //assertEquals("Result is 80 CZK");
2.49 + assertNotNull( a1 );
2.50 + assertEquals( 80.0, a1.getAmount().doubleValue() );
2.51 + assertEquals( CZK, a1.getCurrency() );
2.52
2.53 // convert $8 to CZK using c:
2.54 + final Convertor.ConversionResult r2 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 8, USD ), CZK ) );
2.55 + final MonetaryAmount a2 = r2.getNetAmount();
2.56 //assertEquals("Result is 127.92 CZK");
2.57 + assertNotNull( a2 );
2.58 + assertEquals( 12792.0, a2.getAmount().movePointRight( 2 ).doubleValue() );
2.59 + assertEquals( CZK, a2.getCurrency() );
2.60
2.61 // convert $1 to CZK using c:
2.62 + final Convertor.ConversionResult r3 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 1, USD ), CZK ) );
2.63 + final MonetaryAmount a3 = r3.getNetAmount();
2.64 //assertEquals("Result is 15.98 CZK");
2.65 + assertNotNull( a3 );
2.66 + assertEquals( 1598.0, a3.getAmount().movePointRight( 2 ).doubleValue() );
2.67 + assertEquals( CZK, a3.getCurrency() );
2.68
2.69 // convert 15.97CZK to USD using c:
2.70 + final BigDecimal s4 = new BigDecimal( 1597 ).movePointLeft( 2 );
2.71 + final Convertor.ConversionResult r4 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( s4, CZK ), USD ) );
2.72 + final MonetaryAmount a4 = r4.getNetAmount();
2.73 //assertEquals("Result is 1$");
2.74 -
2.75 - fail("Implement me!");
2.76 + assertNotNull( a4 );
2.77 + assertEquals( 1.0, a4.getAmount().doubleValue() );
2.78 + assertEquals( USD, a4.getCurrency() );
2.79 }
2.80
2.81 /** Join the convertors and show they behave sane.
2.82 @@ -88,16 +119,26 @@
2.83 return;
2.84 }
2.85
2.86 - Convertor c = Task2Test.merge(
2.87 + final Convertor c = Task2Test.merge(
2.88 createOnlineCZKUSDConvertor(),
2.89 Task1Test.createSKKtoCZK()
2.90 );
2.91
2.92 - // convert 16CZK to SKK using c:
2.93 + // convert 16CZK using c:
2.94 + final Convertor.ConversionResult r4 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 16, CZK ), SKK ) );
2.95 + final MonetaryAmount a4 = r4.getNetAmount();
2.96 // assertEquals("Result is 20 SKK");
2.97 + assertNotNull( a4 );
2.98 + assertEquals( 20.0, a4.getAmount().doubleValue() );
2.99 + assertEquals( SKK, a4.getCurrency() );
2.100
2.101 // convert 500SKK to CZK using c:
2.102 + final Convertor.ConversionResult r5 = c.convert( new Convertor.ConversionRequest( new MonetaryAmount( 500, SKK ), CZK ) );
2.103 + final MonetaryAmount a5 = r5.getNetAmount();
2.104 // assertEquals("Result is 400 CZK");
2.105 + assertNotNull( a5 );
2.106 + assertEquals( 400.0, a5.getAmount().doubleValue() );
2.107 + assertEquals( CZK, a5.getCurrency() );
2.108
2.109 doFewQueriesForOnlineConvertor(c);
2.110 }