重构2-Move Method（方法移动）

重构同样非常简单，以至于人们并不认为这是一个有价值的重构。迁移方法（Move Method），顾名思义就是将方法迁移到合适的位置。在开始重构前，我们先看看一下代码：

public class BankAccount {
    public BankAccount(int accountAge, int creditScore, AccountInterest accountInterest) {
        AccountAge = accountAge;
CreditScore = creditScore;
AccountInterest = accountInterest;
}
    public int AccountAge{get;private set ;}

    public int CreditScore{get;private set ;}

    public AccountInterest AccountInterest {get;private set ; }

    public double CalculateInterestRate() {
        if (CreditScore > 800) return 0.02;
        if (AccountAge > 10) return 0.03;
        return 0.05;
}
}

public class AccountInterest {
    public BankAccount Account{get;private set ;}
    public AccountInterest(BankAccount account) {
        Account = account;
}
    public double InterestRate{
        get {
            return Account.CalculateInterestRate();
}
    }
    public bool IntroductoryRate{
        get {
        return Account.CalculateInterestRate() < 0.05;
}
    }
}

这里值得注意的是BankAccount.CalculateInterest方法。当一个方法被其他类使用比在它所在类中的使用还要频繁时，我们就需要使用迁移方法重构了——将方法迁移到更频繁地使用它的类中。由于依赖关系，该重构并不能应用于所有实例，但人们还是经常低估它的价值。 最终的代码应该是这样的：

public class BankAccount {
    public BankAccount(int accountAge, int creditScore, AccountInterest accountInterest) {
        AccountAge = accountAge;
CreditScore = creditScore;
AccountInterest = accountInterest;
}
    public int AccountAge { get; private set; }
    public int CreditScore { get; private set; }
    public AccountInterest AccountInterest {get;private set;}
}

public class AccountInterest {
    public BankAccount Accountm{ get; private set ; }
    public AccountInterest(BankAccount account) {
        Account = account;
}

    public double InterestRate {
        get {
            return CalculateInterestRate();
}
    } 
    public bool IntroductoryRate {
        get {
            return CalculateInterestRate() < 0.05;
}
    }

    public double CalculateInterestRate() {
        if (Account.CreditScore > 800) return 0.02;
        if (Account.AccountAge > 10) return 0.03;
        return 0.05;
}
}

简单吧。。

 

 

来自为知笔记(Wiz)