1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/task2/solution08/src/org/apidesign/apifest08/currency/Convertor.java	Wed Oct 01 10:43:05 2008 +0200
     1.3 @@ -0,0 +1,55 @@
     1.4 +package org.apidesign.apifest08.currency;
     1.5 +
     1.6 +import java.util.Currency;
     1.7 +import java.util.Hashtable;
     1.8 +import java.util.Map;
     1.9 +
    1.10 +/** This is the skeleton class for your API. You need to make it public, so
    1.11 + * it is accessible to your client code (currently in Task1Test.java) file.
    1.12 + * <p>
    1.13 + * Feel free to create additional classes or rename this one, just keep all
    1.14 + * the API and its implementation in this package. Do not spread it outside
    1.15 + * to other packages.
    1.16 + */
    1.17 +public class Convertor {
    1.18 +    
    1.19 +    private static final Map<String, Float> EXCHANGE_RATES = new Hashtable<String, Float>() { {
    1.20 +            put("CZKUSD", 1/17F);
    1.21 +            put("USDCZK", 17F);
    1.22 +            put("SKKCZK", 100/80F);
    1.23 +            put("CZKSKK", 80/100F);
    1.24 +        }
    1.25 +    };
    1.26 +    
    1.27 +    private Currency currencyFirst;
    1.28 +    private Currency currencySecond;
    1.29 +    
    1.30 +    private Convertor(Currency currencyFirst, Currency currencySecond) {
    1.31 +        this.currencyFirst = currencyFirst;
    1.32 +        this.currencySecond = currencySecond;
    1.33 +    }
    1.34 +    
    1.35 +    public static Convertor getInstanceFor(Currency currencyFirst, Currency currencySecond) {
    1.36 +        return new Convertor(currencyFirst, currencySecond);
    1.37 +    }
    1.38 +    
    1.39 +    public float convert(float value, Currency toCurrency) {
    1.40 +        if (!toCurrency.equals(currencyFirst) && !toCurrency.equals(currencySecond)) {
    1.41 +            throw new IllegalArgumentException("Unsupported currency for this convertor!: " + toCurrency.getCurrencyCode());
    1.42 +        }
    1.43 +        
    1.44 +        Float rate = null;
    1.45 +        if (toCurrency.equals(currencyFirst)) {
    1.46 +            rate = EXCHANGE_RATES.get(currencyFirst.getCurrencyCode() + currencySecond.getCurrencyCode());
    1.47 +        }
    1.48 +        if (toCurrency.equals(currencySecond)) {
    1.49 +            rate = EXCHANGE_RATES.get(currencySecond.getCurrencyCode() + currencyFirst.getCurrencyCode());
    1.50 +        }
    1.51 +
    1.52 +        if (rate == null) {
    1.53 +            throw new IllegalStateException("Undefinied conversion!");
    1.54 +        }
    1.55 +
    1.56 +        return rate*value;
    1.57 +    }
    1.58 +}