Breakdown of PlayerJoinEvent, PlayerPreLoginEvent and PlayerLoginEvent

A few people wonder what the difference is between the events PlayerJoinEvent, PlayerPreLoginEvent and PlayerLoginEvent.

The short and simple answer is: They are all called on successful login.

• First: PlayerPreLoginEvent stores raw data (Name and IP) and can be used to ban players.
• Second: PlayerLoginEvent detects if the player should be allowed to join (checking White list, Ban list, IP Ban list, Max Players) then letting plugins edit the result.
• Lastly, PlayerJoinEvent gets called if the player is allowed to join, and you can set the join message.

PlayerPreLoginEvent
This event stores the following data:

• result: Is the player allowed to login? (default "Allowed")
• message: message to display on "kick"
• name: Users name attempting to login
• ipAddress: Address of user trying to login

This is not a "player" event, and as such .getPlayer() doesn't exist.

PlayerLoginEvent
Now here's what I've been finding people do wrong, in my opinion. People use PlayerLogin as a place to set player information. Now, I could say this is alright, except that I must say this is completely wrong for you to do. This event should be used to validate the players login, and apply permissions to a player. What you should not try to do is set player information (eg: DisplayName). Yes, it is a convenient place for you to set the display name, but you should do this in the PlayerJoinEvent, where the player actually joins the server.
The following data is stored:

• Player: the player logging in
• result: The result of login
  • ALLOWED
  • KICK_FULL (server full)
  • KICK_BANNED (banned ip/name)
  • KICK_WHITELIST (not on whitelist)
  • KICK_OTHER (other, can set by plugins)
• message: The message to display on "kick"

An example of code for applying permissions:

Code:

// register code in main java file
getServer().getPluginManager().registerEvent(Event.Type.PLAYER_LOGIN, new playerListener(this), Event.Priority.Monitor, this); // and yes. I'm serious about using monitor.

public void onPlayerLogin(PlayerLoginEvent event) {
    if(event.getResult() == PlayerLoginEvent.Result.ALLOWED)
        registerPlayer(event.getPlayer());
}

PlayerJoinEvent
This is where you should play around with the player information. Data stored:

• Player: The player joining
• Message: the message to broadcast on join. (set to null for no message)

I hope this was helpful to some people. Like.... @codename_B

 

Ermm...

https://github.com/codename-B/bPerm...ermissions/PermissionsPlayerListener.java#L20

 

@codename_B : Still missing the most vital "if(event.getResult() != PlayerLoginEvent.Result.ALLOWED) return;"

EDIT: Oh I see. You use "low"

 

Humm, isn't PreLogin only called if the server is online-mode=true?

 

I didn't check. And for the sake of bukkit promoting online-mode, it doesn't matter.

 

Just curious, could you force a player to be logged in as someone else if you changed the name property in PlayerPreLoginEvent?

 

You can not setName, you can only get.

 

Breaks all the rules about accessing out of scope, and would technically change the name variable, but would it change the name the that actually logs in, and if so, would the minecraft.net premium account check happen before or after this?

Code:java

public void onPlayerPreLogin(PlayerPreLoginEvent event)
{
    try
    {
        PlayerPreLoginEvent.class
            .getField("name")
            .set(event, "newusername");
    }
    catch (Exception e)
    {
        // PlayerPreLoginEvent has no field called "name"
    }
}

 

It would not. Since the event doesn't allow setting of the field normally, bukkit doesn't get the field to use as the players name. It's simply a holder for people to know who is logging in if they listen to the event.

 

May I ask which event you would use to check if this player is new aka checking up their player.dat file? which event would this not be created in?

 

I have not looked into this, I could look for it after I wake up in a few hours though.

This is a wild guess: but logically thinking, it would be created on player join... but I don't know. I will try and see.

 

Thank you