task3/solution12/src/org/apidesign/apifest08/currency/Convertor.java
changeset 51 221f1930cbfb
parent 45 251d0ed461fb
     1.1 --- a/task3/solution12/src/org/apidesign/apifest08/currency/Convertor.java	Tue Oct 07 11:05:34 2008 +0200
     1.2 +++ b/task3/solution12/src/org/apidesign/apifest08/currency/Convertor.java	Fri Oct 10 21:48:49 2008 +0200
     1.3 @@ -20,19 +20,35 @@
     1.4  
     1.5    private static Hashtable<String, ExchangeRate> exchangeRates;
     1.6  
     1.7 -  private Hashtable<String, ExchangeRate> convertorInstanceExchangeRates; 
     1.8 +  private List<String> currencyConvertors; 
     1.9  
    1.10 -  private Convertor(List<Currency> currencies) throws UnknownConvertorException {
    1.11 -	  convertorInstanceExchangeRates = new Hashtable<String, ExchangeRate>();
    1.12 -	  for (Currency currency1 : currencies) {
    1.13 -		for (Currency currency2 : currencies) {
    1.14 -			if(!currency1.getCurrencyCode().equals(currency2.getCurrencyCode())) {
    1.15 -				String key = currency1.getCurrencyCode() + currency2.getCurrencyCode();
    1.16 -				ExchangeRate exchangeRate = exchangeRates.get(key);
    1.17 -				convertorInstanceExchangeRates.put(key, exchangeRate);
    1.18 -			}
    1.19 -		}
    1.20 -	}
    1.21 +  /**
    1.22 +   * Constructor. Checks if all selected currencies are not null and has defined exchange rates for both
    1.23 +   * directions.
    1.24 +   * @param currencies currencies for new instance of convertor
    1.25 +   * @throws UnknownConvertorException if there are not defined exchange rates for both directions for each
    1.26 +   * pair of currencies
    1.27 +   */
    1.28 +  private Convertor(Currency[] currencies) throws UnknownConvertorException {
    1.29 +    currencyConvertors = new ArrayList<String>();
    1.30 +
    1.31 +    for (Currency currency1 : currencies) {
    1.32 +      for (Currency currency2 : currencies) {
    1.33 +        if(currency1 == null || currency2 == null) {
    1.34 +          throw new ConvertorException("None of the currencies should be null!!!");
    1.35 +        }
    1.36 +          
    1.37 +        if(!currency1.getCurrencyCode().equals(currency2.getCurrencyCode())) {
    1.38 +          String key = currency1.getCurrencyCode() + currency2.getCurrencyCode();
    1.39 +          if (!exchangeRates.containsKey(key)) {
    1.40 +            throw new UnknownConvertorException("Selected convertor (" + currency1.getCurrencyCode() + "->"
    1.41 +                + currency2.getCurrencyCode() + ") has not defined exchange rates!!!");
    1.42 +          } 
    1.43 +          
    1.44 +          currencyConvertors.add(key);            
    1.45 +        }
    1.46 +      }
    1.47 +    }
    1.48    }
    1.49  
    1.50    /**
    1.51 @@ -77,7 +93,11 @@
    1.52     * @return convertor with merged exchange rates 
    1.53     */
    1.54    public Convertor merge(Convertor convertor) {
    1.55 -	  convertorInstanceExchangeRates.putAll(convertor.getInstanceExchangeRates());
    1.56 +    if(convertor == null) {
    1.57 +      throw new ConvertorException("It's impossible to merge with null convertor!!!");
    1.58 +    }
    1.59 +    
    1.60 +    currencyConvertors.addAll(convertor.getCurrencyConvertors());
    1.61  	  return this;
    1.62    }
    1.63  
    1.64 @@ -92,32 +112,11 @@
    1.65     *           thrown if convertor for selected currencies has not been defined
    1.66     */
    1.67    public static Convertor getConvertorInstance(Currency... currencies) throws UnknownConvertorException {
    1.68 -   	List<Currency> currencyList = new ArrayList<Currency>();
    1.69 -   	
    1.70     	if(currencies.length < 2) {
    1.71     		throw new ConvertorException("To get convertor instance, you have to select at least two currencies!!!");
    1.72     	}
    1.73 -
    1.74 -   	for (Currency currency1 : currencies) {
    1.75 -   		for (Currency currency2 : currencies) {
    1.76 -   	   		if(currency1 == null || currency2 == null) {
    1.77 -   	   			throw new ConvertorException("None of the currencies should be null!!!");
    1.78 -   	   		}
    1.79 -   	   		
    1.80 -   			if(!currency1.getCurrencyCode().equals(currency2.getCurrencyCode())) {
    1.81 -   				String key12 = currency1.getCurrencyCode() + currency2.getCurrencyCode();
    1.82 -   				String key21 = currency2.getCurrencyCode() + currency1.getCurrencyCode();
    1.83 -   				if (!(exchangeRates.containsKey(key12) && exchangeRates.containsKey(key21))) {
    1.84 -   					throw new UnknownConvertorException("Selected convertor (" + currency1.getCurrencyCode() + "<->"
    1.85 -   		    			+ currency2.getCurrencyCode() + ") has not defined exchange rates!!!");
    1.86 -   				}
    1.87 -   			}
    1.88 -		}
    1.89 -   		
    1.90 -   		currencyList.add(currency1);
    1.91 -	}
    1.92      
    1.93 -    return new Convertor(currencyList);
    1.94 +    return new Convertor(currencies);
    1.95    }
    1.96  
    1.97    /**
    1.98 @@ -163,8 +162,8 @@
    1.99      
   1.100      String key = originalCurrency.getCurrencyCode() + newCurrency.getCurrencyCode();
   1.101  
   1.102 -    if(convertorInstanceExchangeRates.containsKey(key)) {
   1.103 -      actualyUsedExchangeRate = convertorInstanceExchangeRates.get(key);
   1.104 +    if(currencyConvertors.contains(key)) {
   1.105 +      actualyUsedExchangeRate = exchangeRates.get(key);
   1.106      } else {
   1.107        throw new InvalidCurrencyException("This convertor could not be used for converting selected currencies (" + originalCurrency.getCurrencyCode() + "->"
   1.108            + newCurrency.getCurrencyCode() + ") !!!");
   1.109 @@ -174,11 +173,11 @@
   1.110    }
   1.111    
   1.112    /**
   1.113 -   * Returns exchange rates for actual instance of convertor.
   1.114 -   * @return exchange rates for actual instance of convertor
   1.115 +   * Returns currency convertors for actual instance of convertor.
   1.116 +   * @return currency convertors for actual instance of convertor
   1.117     */
   1.118 -  Hashtable<String, ExchangeRate> getInstanceExchangeRates() {
   1.119 -	  return convertorInstanceExchangeRates;
   1.120 +  List<String> getCurrencyConvertors() {
   1.121 +	  return currencyConvertors;
   1.122    }
   1.123    
   1.124  }