重构：Move Method

来源：互联网发布：知乎费县夫妻刑警笔录编辑：程序博客网时间：2024/06/05 14:47

在重构：extract method篇中的，amountFor函数应该搬家到Rental类中。

public class Rental {    private Movie _mMovie;    private int _daysRented;    public Rental(Movie movie, int daysRented) {        // TODO Auto-generated constructor stub        _mMovie = movie;        _daysRented = daysRented;    }    public int getDaysRented() {        return _daysRented;    }    public Movie getMovie() {        return _mMovie;    }    public double getCharge() {        double  result = 0;        switch (getMovie().getPriceCode()) {        case Movie.REGULAR:            result +=2;            if(getDaysRented() > 2){                result +=(getDaysRented() -2) * 1.5;            }            break;            case Movie.NEW_RELEASE:                result += getDaysRented() * 3;                break;            case Movie.CHILDRENS:                result += 1.5;                if(getDaysRented() > 3){                    result += (getDaysRented() - 3)* 1.5;                }        default:                        break;        }        return result;    }}

public class Customer {    private String _name;    private Vector<Rental> _rentals = new Vector<Rental>();;    public Customer(String name) {        _name = name;    }    public void addRental(Rental arg) {        _rentals.addElement(arg);    }    public String getName() {        return _name;    }    public String statement() {        double totalAmount = 0;        int frequentRenterPoints = 0;        Enumeration<Rental> rentals = _rentals.elements();        String result = "Rental Record For " + getName() + "\n";        while (rentals.hasMoreElements()) {            double thisAmount = 0;            Rental each = (Rental) rentals.nextElement();            thisAmount = amountFor(each);            frequentRenterPoints++;            if ((each.getMovie().getPriceCode() == Movie.NEW_RELEASE) && each.getDaysRented() > 1) {                frequentRenterPoints++;            }            result += "\t" + each.getMovie().getTitle() + "\t" + String.valueOf(thisAmount) + "\n";            totalAmount += thisAmount;        }        result += "Amount owed is " + String.valueOf(totalAmount) + "\n";        result += "You earned " + String.valueOf(frequentRenterPoints) + " frequent renter points";        return result;    }    private double amountFor(Rental aRental) {        return aRental.getCharge();    }}

方法搬家后直接调用：

public class Customer {    private String _name;    private Vector<Rental> _rentals = new Vector<Rental>();;    public Customer(String name) {        _name = name;    }    public void addRental(Rental arg) {        _rentals.addElement(arg);    }    public String getName() {        return _name;    }    public String statement() {        double totalAmount = 0;        int frequentRenterPoints = 0;        Enumeration<Rental> rentals = _rentals.elements();        String result = "Rental Record For " + getName() + "\n";        while (rentals.hasMoreElements()) {            double thisAmount = 0;            Rental each = (Rental) rentals.nextElement();            thisAmount = each.getCharge();            frequentRenterPoints++;            if ((each.getMovie().getPriceCode() == Movie.NEW_RELEASE) && each.getDaysRented() > 1) {                frequentRenterPoints++;            }            result += "\t" + each.getMovie() + "\n";            totalAmount += thisAmount;        }        result += "Amount owed is " + String.valueOf(totalAmount) + "\n";        result += "You earned " + String.valueOf(frequentRenterPoints) + " frequent renter points";        return result;    }}

0 0