使用除去临时变量继续重构（2）

使用除去临时变量继续重构（2）

然后以同样手法处理frequentRenterPoints:
class Customer...
public String statement() {
    int frequentRenterPoints = 0;
    Enumeration rentals = _rentals.elements();
    String result = "Rental Record for * " + getName() + "\n";
    while(rentals.hasMoreElements()) {
       Rental each = (Rental)rentals.nextElement();    //取得一笔租借记录

     frequentRenterPoints += each.getFrequentRenterPoints();

          result += "\t" + each.getMovie().getTitle() + "\t" +
             String.valueOf(each.getCharge()) + "\n";
    }
//   add footer lines(结尾打印)
    result += "Amount owed is " + String.valueOf(getTotalCharge()) + " \n";
    result += "You earned " + String.valueOf( frequentRenterPoints) +
       "frequent renter points";
    return result;
}

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public String statement() {
    Enumeration rentals = _rentals.elements();
    String result = "Rental Record for * " + getName() + "\n";
    while(rentals.hasMoreElements()) {
       Rental each = (Rental)rentals.nextElement();    //取得一笔租借记录

          result += "\t" + each.getMovie().getTitle() + "\t" +
             String.valueOf(each.getCharge()) + "\n";
    }
//   add footer lines(结尾打印)
    result += "Amount owed is " + String.valueOf(getTotalCharge()) + " \n";
    result += "You earned " + String.valueOf( getTotalfrequentRenterPoints()) +
       "frequent renter points";
    return result;
}

// 译注：此即所谓 query method
private int getTotalFrequentRenterPoints() {
    int result = 0;
    Enumeration rentals = _rentals.elements();
    while(rentals.hasMoreElements()) {
         Rental each = (Rental)rentals.nextElement();
         result += each.getFrequentRenterPoints();
    }
    return result;
}