Default event Handler Implementation

[Leodagan]

I created a IDOLEventHandler Interface.

Once it's implemented in a class it provide a "void Notify(DOLEvent e, object sender, EventArgs args);" method to any object who would need event notification.

I can just add this Interface to some objects like Brain and GameObject without any modification to test them for Event Handling compatibility ! (they already implement the Notify() Handler)

useful for

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if(object is IDOLEventHandler) { object.Notify(dolevent, this, new EventArgs()); }

Is it a good idea to use this kind of interface in objects needing notifications ?

[Graveen]

Can you provide some (quick) examples in this post of in the SVN commit ? Thank you !

[Leodagan]

I'll use my LosCheck Manager as example :

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/// <summary> /// Dictionary holding a list of object needing Notify /// </summary> private Dictionary<int, List<IDOLEventHandler>> m_registeredLosEvents = new Dictionary<int, List<IDOLEventHandler>>(); private void AddRegisteredEvent(int key, object notifier) { if(notifier is IDOLEventHandler) RegisteredLosEvents[key].Add(notifier); } private static void NotifyObjects(IEnumerable<IDOLEventHandler> notifiers) { foreach(IDOLEventHandler notif in notifiers) notif.Notify(DOLEvent e, this, new EventArgs()); }

This allow to identify clearly which object are supporting "Notify()"

[Ephemeral]

For reference the reason that there wasn't an interface for this in the first place is because there was no point for it, that isn't how delegates are supposed to be specified, all they have to do is match the function signature, which in the case of things like static event handlers is the only way it can be done because interfaces do not allow you to have static functions in them.

[Leodagan]

From what I remember "Notify" in GameObject class and subclass, aren't static method. (maybe in other class I haven't checked)

Nor they are Delegate, DOL Event Mgr seems to check class type for specific one that can receive Notify message or not...

Looks totally like a case where to use an interface

Or I get something wrong ?

[Ephemeral]

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/// <summary> /// Caches the DBPrivilegeGroup from the database to PrivilegeGroups within /// the server's memory for quick lookup and management. /// </summary> [GameServerStartedEvent] public static void LoadGroupCache(DOLEvent e, object sender, EventArgs arguments) { if (ServerProperties.Properties.USE_NEW_PRIVILEGE_SYSTEM) { Log.Info("[Privilege Manager] Loading Groups Cache."); UpdateDefaults(); m_groupCache = new Dictionary<int, PrivilegeGroup>(); m_parameterizedTypeCache = LoadParameterizedCache(); Log.Info("[Privilege Manager] Loaded " + m_parameterizedTypeCache.Count + " Parameterized Type Bindings."); IList<PrivilegeGroup> tmpGroups = GameServer.Database.SelectAllObjects<DBPrivilegeGroup>().Select(dbGrp => new PrivilegeGroup(dbGrp)).ToList(); foreach (PrivilegeGroup privilegeGroup in tmpGroups) { privilegeGroup.Initialize(); m_groupCache.Add(privilegeGroup.DBEntry.GroupIndex, privilegeGroup); } foreach (PrivilegeGroup privilegeGroup in tmpGroups) { privilegeGroup.ResolveGroups(); } foreach (PrivilegeGroup privGrp in tmpGroups.Where(privGrp => privGrp.HasCircularInheritanceChain())) { Log.Error("[Privilege Manager] Group has Circular Inheritance Chain -> " + privGrp.DBEntry.Name); m_groupCache.Remove(privGrp.DBEntry.GroupIndex); } WhoBinding whoBinding = (WhoBinding) GetParameterizedPrivilege("who", new[]{"derp", "herp"}); Log.Error(String.Format("[Privilege Manager] Has Indexed under derp? {0}{1}", whoBinding.IsIndexedAs("derp"), whoBinding.IsIndexedAs("derp") ? " yes it is as -> " + whoBinding.GetAliasFor("derp") : " is not indexed")); } }

Example of a static event handler, and an example of why an interface isn't needed, if you looking around the core you're going to find more instances of static event handlers that are just made by matching the function signature and being manually registered or loaded with reflection.