Reflection Example

reflection_example.cs

using System;
using System.Reflection;
using System.Collections.Generic;
using System.Linq;

interface IRessetable
{
	void Reset();
}

class CredentialStorage: IRessetable
{
	public void Reset() 
	{
		Console.WriteLine("Executing CredentialStorage.Reset");
	}
}

class FavoriteStorage: IRessetable
{
	public void Reset() 
	{
		Console.WriteLine("Executing FavoriteStorage.Reset");
	}
}

class SettingsStorage: IRessetable
{
	public void Reset() 
	{
		Console.WriteLine("Executing SettingsStorage.Reset");
	}
}

class UserSession: IRessetable
{
	public CredentialStorage credentialStorage;
	public FavoriteStorage favoriteStorage;
	public SettingsStorage settingsStorage;
	public bool test;
	
	public UserSession(
		CredentialStorage cd, 
		FavoriteStorage fs,
		SettingsStorage ss
	) {
		this.credentialStorage = cd;
		this.favoriteStorage = fs;
		this.settingsStorage = ss;
		this.test = false;
	}
	
	public void Reset() 
	{				
		ResettableProps().ForEach(x => x.Reset());
	}
	
	private List<IRessetable> ResettableProps()
	{
		return this
			.GetType()
			.GetFields()
			.Select(x => x.GetValue(this))
			.AsQueryable()
			.OfType<IRessetable>()
			.Cast<IRessetable>()
			.ToList();
	}
}

class Activity
{
	static void Main(string[] args)
	{
		UserSession session = new UserSession(
			new CredentialStorage(), 
			new FavoriteStorage(),
			new SettingsStorage()
		);
		session.Reset();
	}
}

/* Output:

Executing CredentialStorage.reset
Executing FavoriteStorage.reset
Executing SettingsStorage.reset

*/

reflection_example.kt

import kotlin.reflect.full.memberProperties
import kotlin.reflect.jvm.*
import kotlin.reflect.jvm.internal.*

interface Resettable {
    fun reset()
}

class CredentialStorage : Resettable {
    override fun reset() {
        println("Executing CredentialStorage.reset")
    }
}

class FavoriteStorage : Resettable {
    override fun reset() {
        println("Executing FavoriteStorage.reset")
    }
}

class SettingsStorage : Resettable {
    override fun reset() {
        println("Executing SettingsStorage.reset")
    }
}

class UserSession(
        val credentials: CredentialStorage,
        val favorites: FavoriteStorage,
        val settings: SettingsStorage
) : Resettable {
    override fun reset() {
        resettableProps().forEach { it.reset() }
    }

    fun resettableProps(): List<Resettable> {
        return UserSession::class.memberProperties
                .map { it.get(this) }
                .filterIsInstance<Resettable>()
    }
}

val session = UserSession(
        CredentialStorage(),
        FavoriteStorage(),
        SettingsStorage()
)

println(session.reset())

/* Output:

Executing CredentialStorage.reset
Executing FavoriteStorage.reset
Executing SettingsStorage.reset

*/

reflection_example.swift

// https://www.swiftbysundell.com/posts/reflection-in-swift

class CredentialStorage {}
class FavoriteStorage {}
class SettingsStorage {}

protocol Resettable {
    func reset()
}

extension CredentialStorage: Resettable {
    func reset() {
        print("Executing CredentialStorage.reset")
    }
}

extension FavoriteStorage: Resettable {
    func reset() {
        print("Executing FavoriteStorage.reset")
    }
}

extension SettingsStorage: Resettable {
    func reset() {
        print("Executing SettingsStorage.reset")
    }
}

extension Mirror {
    func findProperties<T>(ofType type: T.Type) -> [T] {
        return children.compactMap({ $0.value as? T })
    }
}

class UserSession: Resettable {
    let credentials: CredentialStorage
    let favorites: FavoriteStorage
    let settings: SettingsStorage
    
    init(credentials: CredentialStorage, favorites: FavoriteStorage, settings: SettingsStorage) {
        self.credentials = credentials
        self.favorites = favorites
        self.settings = settings
    }
    
    private var resettableProps: [Resettable] {
        return Mirror(reflecting: self).findProperties(ofType: Resettable.self)
    }
    
    func reset() {
        resettableProps.resetEach()
    }
}

extension Array where Element == Resettable  {
    func resetEach() {
        forEach({ $0.reset() })
    }
}

let session = UserSession(
    credentials: CredentialStorage(),
    favorites: FavoriteStorage(),
    settings: SettingsStorage()
)

session.reset()

/* Output:

Executing CredentialStorage.reset
Executing FavoriteStorage.reset
Executing SettingsStorage.reset

*/