xmlsalesformatter.java

SSD3 Ex5 答案 。

/**
  * This class implements a method that obtains an XML
  * representation of a {@link SalesFormatter} object.
  *
  * @author lll
  * @version  1.0.0
  * @see SalesFormatter
  * @see Sales
  * @see Order
  * @see OrderItem
  * @see XMLSalesFormatter
  */
public class XMLSalesFormatter implements SalesFormatter{
	
    private final static String NEW_LINE =
        System.getProperty("line.separator");
    
    static private XMLSalesFormatter singletonInstance = null;

    static public XMLSalesFormatter getSingletonInstance(){
    	
        if (singletonInstance == null) {
            singletonInstance = new XMLSalesFormatter();
        }

        return singletonInstance;

    }
    private XMLSalesFormatter(){
    	
    }
    public String formatSales(Sales sales){
    	
    	String out="<Sales>" + NEW_LINE ;
    	
    	for(Order order:sales)
		{
    		out+= " <Order total=\""
 		   + order.getTotalCost()
 		   + "\">"
 		   + NEW_LINE;
			for(OrderItem items:order)
			{
				
				 out +="  <OrderItem quantity=\""
					   +items.getQuantity()
					   +"\" price=\""
					   +items.getProduct().getPrice()
					   +"\">"+items.getProduct().getCode()
					   +"</OrderItem>"+NEW_LINE;
				
			}
			out+= " </Order>"+NEW_LINE;
		}
    	out+="</Sales>";
    	return out;

    }
}