Strategy Pattern

2024-06-30

Strategy Pattern

※ 情境 : 當有許多僅在執行某些行為時略有不同的相似類時，可使用策略模式。

Interface

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type Transportation interface {
	travel()
}

Strategies

type Car struct {
}

func (c *Car) travel() {
	fmt.Println("Travel by car")
}

type Scooter struct {
}

func (s *Scooter) travel() {
	fmt.Println("Travel by scooter")
}

type Train struct {
}

func (t *Train) travel() {
	fmt.Println("Travel by train")
}

Execute func

func NewTransportation(strategyType string) Transportation {
	switch strategyType {
	case "car":
		return &Car{}
	case "scooter":
		return &Scooter{}
	case "train":
		return &Train{}
	default:
		return nil
	}
}

func NavigateToTarget(strategy Transportation) {
	strategy.travel()
}

Test

package test

import (
	"DesignPatterns/StrategyPattern"
	"testing"
)

func TestStrategyPattern(t *testing.T) {
	strategy := StrategyPattern.NewTransportation("scooter")

	if strategy == nil {
		t.Error("Invalid transportation strategy")
	}

	StrategyPattern.NavigateToTarget(strategy)
}