Flyweight

동일하거나 유사한 객체들 사이에 가능한 많은 데이터를 서로 공유하여 사용하도록 하여 메모리 사용량을 최소화하는 소프트웨어 디자인 패턴이다. 

 

https://refactoring.guru/design-patterns/flyweight

 

class diagram

 

https://refactoring.guru/design-patterns/flyweight

 

예제

public class HeavyObject
{
    private readonly string _name;
    private readonly int _age;

    public HeavyObject(string name, int age)
    {
        Thread.Sleep(TimeSpan.FromSeconds(1));
        _name = name;
        _age = age;
    }
    public void Execution()
    {
        Console.WriteLine($"Name : {_name} , Age : {_age}, !! Long live Ukraine !! хай живе україна !!");
    }

}

public class HeavyObjectFactory
{
    private Dictionary<string, HeavyObject> _pool = new Dictionary<string, HeavyObject>();
    public HeavyObject Get(string name, int age)
    {
        string key = $"{name}{age}";
        if (!_pool.ContainsKey(key))
        {
            var obj = new HeavyObject(name,age);
            _pool.Add(key, obj);
            return obj;
        }
        return _pool[key];
    }
}

사용법

var factory = new HeavyObjectFactory();

var heavyObjects = new List<HeavyObject>();
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
heavyObjects.Add(factory.Get("Putin", 69));
heavyObjects.Add(factory.Get("Biden", 79));
heavyObjects.Add(factory.Get("Zelensky", 44));
stopwatch.Stop();
Console.WriteLine($"첫번째 초기화시 걸린 시간 {stopwatch.ElapsedMilliseconds}ms");

stopwatch.Restart();
heavyObjects.Add(factory.Get("Biden", 79));
heavyObjects.Add(factory.Get("Putin", 69));
heavyObjects.Add(factory.Get("Zelensky", 44));
stopwatch.Stop();
Console.WriteLine($"두번째 초기화시 걸린 시간 {stopwatch.ElapsedMilliseconds}ms");

foreach (var heavyObject in heavyObjects)
    heavyObject.Execution();
// output
첫번째 초기화시 걸린 시간 3034ms
두번째 초기화시 걸린 시간 0ms
Name : Putin , Age : 69, !! Stay strong Ukraine! You will definitely win! !! Будь сильною Укра?но! Ви точно переможете! !!
Name : Biden , Age : 79, !! Stay strong Ukraine! You will definitely win! !! Будь сильною Укра?но! Ви точно переможете! !!
Name : Zelensky , Age : 44, !! Stay strong Ukraine! You will definitely win! !! Будь сильною Укра?но!  Ви точно переможете! !!
Name : Biden , Age : 79, !! Stay strong Ukraine! You will definitely win! !! Будь сильною Укра?но! Ви точно переможете! !!
Name : Putin , Age : 69, !! Stay strong Ukraine! You will definitely win! !! Будь сильною Укра?но! Ви точно переможете! !!
Name : Zelensky , Age : 44, !! Stay strong Ukraine! You will definitely win! !! Будь сильною Укра?но!  Ви точно переможете! !!

 

 

관련영상

https://youtu.be/MPjYcc_fHn0