exercise 5.plaintextsalesformatter.java

来自「ssd3的全部答案」· Java 代码 · 共 69 行

import java.util.*;

/**
 * This class implements the interface SalesFormatter. This class is implemented
 * as a singleton so a new object will not be created every time the plain-text
 * format is used.
 * 
 * @author Neil
 * @version 1.1.0
 * @see Order
 * @see OrderItem
 * @see Product
 */
public class PlainTextSalesFormatter implements SalesFormatter {

	private static PlainTextSalesFormatter singletonInstance = null;

	/**
	 * Static method that obtains the single instance of class
	 * PlainTextsalesFormatter.
	 * 
	 * @return the single instance of class PlainTextsalesFormatter.
	 */
	public static PlainTextSalesFormatter getSingletonInstance() {

		if (singletonInstance == null)
			singletonInstance = new PlainTextSalesFormatter();

		return singletonInstance;
	}

	/**
	 * Constructor that is declared private so it is inaccessible to other
	 * classes. A private constructor makes it impossible for any other class to
	 * create an instance of class PlainTextSalesFormatter.
	 */
	private PlainTextSalesFormatter() {

	}

	/**
	 * Produces a string that contains the specified sales information in a
	 * plain-text format.
	 * 
	 * @return a string that contains the specified sales information in a
	 *         plain-text format.
	 */
	public String formatSales(Sales sales) {

		int k = 0;
		String result = "";

		for (Iterator<Order> i = sales.iterator(); i.hasNext();) {
			Order order = i.next();
			k++;
			result += "\n------------------------\nOrder " + k + "\n\n";
			for (Iterator<OrderItem> j = order.iterator(); j.hasNext();) {
				OrderItem orderItem = j.next();
				result += orderItem.getQuantity() + " "
						+ orderItem.getProduct().getCode() + " "
						+ orderItem.getProduct().getPrice() + "\n";
			}
			result += "\nTotal = " + order.getTotalCost();
		}

		return result;
	}
}