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Patron de méthode

Patron de méthode en Rust

Le Patron de méthode est un patron de conception comportemental qui permet de définir le squelette d’un algorithme dans la classe de base, et laisse les sous-classes redéfinir les étapes sans modifier la structure globale de l’algorithme.

En savoir plus sur la patron Patron de méthode

Conceptual Example

main.rs

trait TemplateMethod {
    fn template_method(&self) {
        self.base_operation1();
        self.required_operations1();
        self.base_operation2();
        self.hook1();
        self.required_operations2();
        self.base_operation3();
        self.hook2();
    }

    fn base_operation1(&self) {
        println!("TemplateMethod says: I am doing the bulk of the work");
    }

    fn base_operation2(&self) {
        println!("TemplateMethod says: But I let subclasses override some operations");
    }

    fn base_operation3(&self) {
        println!("TemplateMethod says: But I am doing the bulk of the work anyway");
    }

    fn hook1(&self) {}
    fn hook2(&self) {}

    fn required_operations1(&self);
    fn required_operations2(&self);
}

struct ConcreteStruct1;

impl TemplateMethod for ConcreteStruct1 {
    fn required_operations1(&self) {
        println!("ConcreteStruct1 says: Implemented Operation1")
    }

    fn required_operations2(&self) {
        println!("ConcreteStruct1 says: Implemented Operation2")
    }
}

struct ConcreteStruct2;

impl TemplateMethod for ConcreteStruct2 {
    fn required_operations1(&self) {
        println!("ConcreteStruct2 says: Implemented Operation1")
    }

    fn required_operations2(&self) {
        println!("ConcreteStruct2 says: Implemented Operation2")
    }
}

fn client_code(concrete: impl TemplateMethod) {
    concrete.template_method()
}

fn main() {
    println!("Same client code can work with different concrete implementations:");
    client_code(ConcreteStruct1);
    println!();

    println!("Same client code can work with different concrete implementations:");
    client_code(ConcreteStruct2);
}

Output

Same client code can work with different concrete implementations:
TemplateMethod says: I am doing the bulk of the work
ConcreteStruct1 says: Implemented Operation1
TemplateMethod says: But I let subclasses override some operations
ConcreteStruct1 says: Implemented Operation2
TemplateMethod says: But I am doing the bulk of the work anyway

Same client code can work with different concrete implementations:
TemplateMethod says: I am doing the bulk of the work
ConcreteStruct2 says: Implemented Operation1
TemplateMethod says: But I let subclasses override some operations
ConcreteStruct2 says: Implemented Operation2
TemplateMethod says: But I am doing the bulk of the work anyway

Patron de méthode dans les autres langues