原型模式(clone)——创建型模式
什么是原型模式?
原型模式是一种创建型设计模式, 使你能够复制已有对象, 而又无需依赖它们所属的类。
总结:需要在继承体系下,实现一个clone接口,在这个方法中以本身作为拷贝源,调用自身拷贝构造函数,并返回新对象地址(用基类指针接收)。
/*************************************************************************> File Name: 8.Clone.cpp> Author:> Mail:> Created Time: Wed Mar 13 17:55:27 2024************************************************************************/#include <iostream>
#include <vector>using namespace std;class Shape {
private:int x, y;
public:Shape() = default;Shape(const Shape &obj) {x = obj.x;y = obj.y;}virtual Shape* clone() = 0;
};class Rectangle : public Shape {
private:int width, height;
public:Rectangle() = default;Rectangle(const Rectangle &obj) : Shape(obj) {width = obj.width;height = obj.height;}Shape* clone() override {return new Rectangle(*this);}
};class Circle : public Shape {
private:int radius;
public:Circle() = default;Circle(const Circle &obj) : Shape(obj) {radius = obj.radius;}Shape* clone() override {return new Circle(*this);}
};vector<Shape *> vec;
vector<Shape *> backup;int main() {Rectangle *rec = new Rectangle();vec.push_back(rec);Circle *cir = new Circle();vec.push_back(cir);for (int i = 0; i < vec.size(); ++i) {backup.push_back(vec[i]->clone());}return 0;
}