Question

我正在使用UML在c ++中为基本代码建模。我有初稿。我想就如何改善它，是否错过了某项内容或图表是否有问题提供反馈。

UML图：

和代码：

#include <ctime>
#include <functional>
#include <iostream>
#include <math.h>
#include <numeric>
#include <string>
#include <vector>


// CLASS: declaration -------------------------------------
// # Animal ...............................................
class Animal{
    private:
        std::string name;
        double height;
        double weight;

        // member of a class as static { bit.ly/2EXnDTW }
        static int numOfAnimals;
    public:
        static int GetNumOfAnimals(){return numOfAnimals;}

        void SetName(std::string name){this->name = name;} //<mutator/SETTER
        std::string GetName(){return name;} //<accessor/GETTER

        void SetHeight(double height){this->height = height;}
        double GetHeight(){return height;}

        void SetWeight(double weight){this->weight = weight;}
        double GetWeight(){return weight;}

        //note: possible not to provide a name here with your prototypes
        //ex: void SetAll(std::string, double, double);
        void SetAll(std::string name, double height, double weight);

        Animal(std::string name, double height, double weight); //<constructor
        Animal(); //<overload constructor when no attributes are passed
        ~Animal(); //<deconstructor

        void ToString();
};

int Animal::numOfAnimals = 0;

void Animal::SetAll(std::string name, double height, double weight){
    this->name = name;
    this->height = height;
    this->weight = weight;
}
//constructor
Animal::Animal(std::string name, double height, double weight){
    this->name = name;
    this->height = height;
    this->weight = weight;
    Animal::numOfAnimals++;
}
//overload constructor when no attributes are passed
Animal::Animal(){
    this->name = "";
    this->height = 0;
    this->weight = 0;
    Animal::numOfAnimals++;
}
//destructor
Animal::~Animal(){ std::cout << "Animal " << this -> name << " destroyed\n";}

void Animal::ToString(){
    std::cout << this -> name << " is "
              << this -> height << " cms tall and "
              << this -> weight << " kgs in weight\n";
}

// # Dog ..................................................
class Dog: public Animal{
    private:
        std::string sound = "woof";
    public:
        void MakeSound(){ printf("The dog %s says %s\n", this->GetName().c_str(), this->sound.c_str());}
        Dog(std::string name, double height, double weight, std::string sound);
        Dog(): Animal(){};
        void ToString();
};

Dog::Dog(std::string name, double height, double weight, std::string sound) :
Animal(name, height, weight){
    this->sound = sound;
}

void Dog::ToString(){
    //printf("%s is %d cms tall and %d kgs in weight and says %s\n",
    //        this->GetName().c_str(), this->GetHeight(), this->GetWeight(), this->sound.c_str());
    // note: do not work well with this->GetHeight() and this->GetWeight()
    std::cout << this -> GetName()   << " is "
              << this -> GetHeight() << " cms tall and "
              << this -> GetWeight() << " kgs in weight and says "
              << this -> sound       << "\n";
}

// END CLASS ----------------------------------------------

int main (int argc, char** argv) {
    //create 1st animal - fred
    Animal fred;
    //test overloaded constructor
    fred.ToString();
    //add attributes value of 1st animal - Fred
    fred.SetHeight(33);
    fred.SetWeight(10);
    fred.SetName("Fred");
    fred.ToString();
    //create 2nd animal using constructor - tom
    Animal tom("Tom", 36, 15);
    tom.ToString();
    //create 1st dog - spot
    Dog spot("Spot", 38, 16, "woofWoof");
    //print 2nd dog info
    spot.ToString();
    spot.MakeSound();
    //print number of animal
    std::cout << "Number of Animals : " << Animal::GetNumOfAnimals() << "\n";
    return 0;
}

代码的预期和当前输出：

身高0厘米，体重0公斤
弗雷德身高33厘米，体重10公斤
汤姆高36厘米，体重15公斤
该点高38厘米，重16公斤，说woofWoof
狗点说woofWoof
动物数：3
动物景点被破坏
汤姆被摧毁的动物
弗雷德被摧毁

Answer 1

可能最好的地方不在这里，而在https://codereview.stackexchange.com/上（仅用于代码）

但是有几句话：

代码和UML建模是一致的，并且可以在没有警告的情况下编译代码，这很好
为什么用A01 : Animal而不是fred : Animal，为什么用A02 : Animal而不是tom : Animal和D01 : Dog而不是spot : Dog？
类图中用于操作参数的符号未遵循UML标准，例如，SetName(string name) : void必须为SetName(in name : string) : void或SetName(name : string) : void（如果隐藏了方向）
我建议您尽可能多地使用 const 操作，例如 getters （ GetName ， GetHeight ...）
在没有参数的构造函数中，您不需要做this->name = "";，幸运的是，std::string作为构造函数可以创建一个空字符串
Animal::ToString()和Dog::ToString()确实不构成字符串，在标准输出上写，它们的名称具有误导性
您声明了析构函数，但未定义它们
因为动物是一个基类，因此将其析构函数 虚拟。万一您从 Animal 指针删除实例实际上是子类的实例，则需要这样做。您错过了递减其中的 numOfAnimals 。
最好让 ToString virtual 根据实例的实际类型而不是编译时已知的类型来调用版本。在 main 中添加{ Animal * a = &spot; a->ToString(); }，然后查看结果。
为什么要在MakeSound()中使用 printf ？
您允许实例化 Animal ，这是一个可以接受的选择，另一种方法也使该类抽象化而仅允许实例化与有效动物相关的子类
我个人仅使用大写字母来开头为 static 的操作（和属性）名称，以区分它们。

P.S。考虑您在S.O.上的照片我很惊讶没有猴子课；-）

如何改善C ++中以下代码的UML建模？

1 个答案: