Prototype Pattern
Intent: Use prototype instances to specify the type of objects to be created, and create new objects by copying these prototypes.
Main issue addressed: Dynamically create and delete prototypes at runtime.
used in qt:
QTableWidgetItem *QTableWidgetItem::clone() const
some codes:
#include <iostream>
#include <memory> // For std::unique_ptr
#include <string>// Prototype class templatetemplate <typename T>
class Prototype {
public:virtual ~Prototype() = default;// Virtual method to clone the objectvirtual std::unique_ptr<T> clone() const = 0;// A method to display object information (can be customized)virtual void display() const = 0;
};// ConcretePrototype class templateclass ConcretePrototype : public Prototype<ConcretePrototype> {
private:std::string name;public:explicit ConcretePrototype(const std::string& name) : name(name) {}// Override the clone function to return a copy of the current objectstd::unique_ptr<ConcretePrototype> clone() const override {return std::make_unique<ConcretePrototype>(*this); // Create a new object as a copy of the current one}void display() const override {std::cout << "ConcretePrototype name: " << name << std::endl;}
};
int main() {// Create an original prototype objectauto original = std::make_unique<ConcretePrototype>("Original");// Display the original objectoriginal->display();// Clone the objectauto clone1 = original->clone();clone1->display(); // Display the cloned object// Clone againauto clone2 = original->clone();clone2->display(); // Display another cloned objectreturn 0;
}