plaintextsalesformatter.java

ssd 3 java程序练习 exercise 5 绝对没有问题

public class PlainTextSalesFormatter implements SalesFormatter {
	static private PlainTextSalesFormatter singletonInstance
    = null;
	static public PlainTextSalesFormatter getSingletonInstance() {
		if (singletonInstance == null) {
            singletonInstance = new PlainTextSalesFormatter();
        }

        return singletonInstance;
	}
	private PlainTextSalesFormatter() {		
	}
	public String formatSales(Sales sales) {
		int number=0;
		double totalCost=0.0;
		String string=new String();
		String NEW_LINE =System.getProperty("line.separator");
		for(Order elementOne :sales) {
			string+=("----------------------"+NEW_LINE);
			number++;
			string+=("Order "+number+NEW_LINE);
			for(OrderItem elementTwo :elementOne) {
				string+=(elementTwo.getQuantity()+" "+
						 elementTwo.getProduct().getCode()+" "+
						 elementTwo.getProduct().getPrice()+NEW_LINE);
				totalCost+=elementTwo.getValue();
			}
			string+=("Total = "+totalCost+NEW_LINE);
		}
		return string;
	}

}