Jump to content

Why does forge create a custom class in ASMEventHandler


codedcosmos

Recommended Posts

I read up on this post and found it rather interesting. So I went into the code and started understanding how it all worked together.

However there was something I found rather curious and have no idea what it's purpose is (though If I had to guess I would say performance). The method in question is called "createWrapper" and is inside the ASMEventHandler class on the forge event bus github. What does this code specifically do for forge. If anyone can shed some light I would be quite grateful.

Link to comment
Share on other sites

Do you want to know what the code does (what the ASM code does and compiles to) or what it is useful for (why it exists)?

About Me

Spoiler

My Discord - Cadiboo#8887

My WebsiteCadiboo.github.io

My ModsCadiboo.github.io/projects

My TutorialsCadiboo.github.io/tutorials

Versions below 1.14.4 are no longer supported on this forum. Use the latest version to receive support.

When asking support remember to include all relevant log files (logs are found in .minecraft/logs/), code if applicable and screenshots if possible.

Only download mods from trusted sites like CurseForge (minecraft.curseforge.com). A list of bad sites can be found here, with more information available at stopmodreposts.org

Edit your own signature at www.minecraftforge.net/forum/settings/signature/ (Make sure to check its compatibility with the Dark Theme)

Link to comment
Share on other sites

It makes an IEventListener that calls an arbitrary method (specifically one marked with @SubscribeEvent) when invoked. 

This allows events to be piped to event handlers without caring what those event handlers are.

The call hierarchy is EventBus.post -> IEventListener.invoke (a ASMEventHandler) -> IEventListener.invoke (ASMEventHandler.handler) -> @SubscribeEvent method

Edited by Cadiboo

About Me

Spoiler

My Discord - Cadiboo#8887

My WebsiteCadiboo.github.io

My ModsCadiboo.github.io/projects

My TutorialsCadiboo.github.io/tutorials

Versions below 1.14.4 are no longer supported on this forum. Use the latest version to receive support.

When asking support remember to include all relevant log files (logs are found in .minecraft/logs/), code if applicable and screenshots if possible.

Only download mods from trusted sites like CurseForge (minecraft.curseforge.com). A list of bad sites can be found here, with more information available at stopmodreposts.org

Edit your own signature at www.minecraftforge.net/forum/settings/signature/ (Make sure to check its compatibility with the Dark Theme)

Link to comment
Share on other sites

The name of the class is in the format ASMEventHandler_ID_callbackClassSimpleName_callbackMethodName_eventSimpleName. I’m using “ExampleClientSubscriber#onModelBake(ModelBakeEvent)” as the callback for the for the example instance event subscriber and “ExampleClientSubscriber.onModelBake(ModelBakeEvent)” as the example callback for the static event subscriber. I’m also assuming the ID is 0. 

 

The generated class looks like

 

1) Instance Event Subscriber

	package net.minecraftforge.eventbus:
	 
	public class ASMEventHandler_0_ExampleClientSubscriber_onModelBake_ModelBakeEvent extends Object implements IEventListener {
	 
	    public Object instance; //this could be made final
	 
	    public ASMEventHandler_0_ExampleClientSubscriber_onModelBake_ModelBakeEvent(Object unnamedParameter) {
	        super();
	        this.instance = unnamedParameter;
	    }
	 
	    @Override //Obviously @Override isn’t actually inserted, I put it here for clarity
	    public void invoke(Event unnamedParameter) {
	        this.instance.onModelBake((ModelBakeEvent) unnamedParameter);
	    }
	 
	}
	

 

2) Static Event Subscriber

(the event parameter isn’t named, but I can’t edit the code block because I’m on mobile)

	package net.minecraftforge.eventbus;
	public class ASMEventHandler_0_ExampleClientSubscriber_onModelBake_ModelBakeEvent extends Object implements IEventListener {
	 
	    public ASMEventHandler_0_ExampleClientSubscriber_onModelBake_ModelBakeEvent() {
	        super();
	    }
	 
	    @Override //Obviously @Override isn’t actually inserted, I put it here for clarity
	    public void invoke(Event event) {
	        // there seems to be an ALOAD 0 here that should only be in the non-static event subscriber? Doesn’t really effect anything though.
	        ExampleClientSubscriber.onModelBake((ModelBakeEvent) event);
	    }
	 
	}
	
Edited by Cadiboo

About Me

Spoiler

My Discord - Cadiboo#8887

My WebsiteCadiboo.github.io

My ModsCadiboo.github.io/projects

My TutorialsCadiboo.github.io/tutorials

Versions below 1.14.4 are no longer supported on this forum. Use the latest version to receive support.

When asking support remember to include all relevant log files (logs are found in .minecraft/logs/), code if applicable and screenshots if possible.

Only download mods from trusted sites like CurseForge (minecraft.curseforge.com). A list of bad sites can be found here, with more information available at stopmodreposts.org

Edit your own signature at www.minecraftforge.net/forum/settings/signature/ (Make sure to check its compatibility with the Dark Theme)

Link to comment
Share on other sites

5 hours ago, codedcosmos said:

Ah so its a common interface, cheers

Its a common interface so that event handler methods don't need to be called with Reflection (which is slow).

Edited by Draco18s

Apparently I'm a complete and utter jerk and come to this forum just like to make fun of people, be confrontational, and make your personal life miserable.  If you think this is the case, JUST REPORT ME.  Otherwise you're just going to get reported when you reply to my posts and point it out, because odds are, I was trying to be nice.

 

Exception: If you do not understand Java, I WILL NOT HELP YOU and your thread will get locked.

 

DO NOT PM ME WITH PROBLEMS. No help will be given.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Announcements



×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.