Custom Events (Two Issues, Both solved)

Issue 1 - SOLVED (open) Issue 1 - SOLVED (close)

Solved. I just needed to change getHandlerList method to static inside my custom events.

So, for my plugin TestqUiz I decided to create a custom event. After reading about custom events, and look at some sources, I realized that it shouldn't be too hard to create a custom event. So I create a bunch of custom events.
Afterward, I created a listener and listend for each event. I registered the listeners in my onEnable, started the plugin, and ... well ... got an error.

Error (open) Error (close)

Code:

21:01:57 [SEVERE] Error occurred while enabling TestqUiz v2.4 (Is it up to date?)
org.bukkit.plugin.IllegalPluginAccessException: java.lang.NullPointerException
    at org.bukkit.plugin.SimplePluginManager.getEventListeners(SimplePluginManager.java:550)
    at org.bukkit.plugin.SimplePluginManager.registerEvents(SimplePluginManager.java:508)
    at me.number1_Master.TestqUiz.TestqUiz.onEnable(TestqUiz.java:59)
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:217)
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:365)
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:381)
    at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:265)
    at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:247)
    at net.minecraft.server.MinecraftServer.i(MinecraftServer.java:296)
    at net.minecraft.server.MinecraftServer.d(MinecraftServer.java:275)
    at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:225)
    at net.minecraft.server.DedicatedServer.init(DedicatedServer.java:140)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:378)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)

Line 58 - 61 I get errors, which are where I register the listeners (with the custom events):

Code (open) Code (close)

Code:java

PreprocessListener ppListener = new PreprocessListener();
IncorrectListener iListener = new IncorrectListener();
CorrectListener cListener = new CorrectListener();
FinishListener fListener = new FinishListener();
// Now for registering the listeners
getServer().getPluginManager().registerEvents(ppListener, this);
getServer().getPluginManager().registerEvents(iListener, this);
getServer().getPluginManager().registerEvents(cListener, this);
getServer().getPluginManager().registerEvents(fListener, this);

I call the event just like any other event: public class className implements Listener then the @EventHandler then public void onEvent(EventName e) and then code. Yet, it throws an error ...

Can I please get information on why this null pointer is occurring? What typiclly causes the error?

Thanks in advance!

Issue 2 - SOLVED (open) Issue 2 - SOLVED (close)

Solved. I was just try to get an empty player

So I finally fixed all startup issues for my plugin, and I went on to testing. I joined, and no errors occurred Nothing bad happened. Since that was done, I decided to start creating my test (since this is a testing plugin).

Now, since I got everything done, it was time to actually test the test. I had three answers to choose from, incorrect, correct, and finish. Since correct is the simplest, I decided to go over that. Well:

Error (open) Error (close)

Code:

2012-08-30 10:48:16 [SEVERE] Could not pass event AnswerPreprocessEvent to TestqUiz
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:332)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at me.number1_Master.TestqUiz.Listeners.PlayerListener.onPlayerMove(PlayerListener.java:40)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:330)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:213)
at net.minecraft.server.Packet10Flying.handle(SourceFile:136)
at net.minecraft.server.NetworkManager.b(NetworkManager.java:276)
at net.minecraft.server.NetServerHandler.d(NetServerHandler.java:109)
at net.minecraft.server.ServerConnection.b(SourceFile:35)
at net.minecraft.server.DedicatedServerConnection.b(SourceFile:30)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:581)
at net.minecraft.server.DedicatedServer.q(DedicatedServer.java:212)
at net.minecraft.server.MinecraftServer.p(MinecraftServer.java:474)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:406)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)
Caused by: java.lang.NullPointerException
at me.number1_Master.TestqUiz.Listeners.PreprocessListener.onPreprocess(PreprocessListener.java:23)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:330)
... 22 more
2012-08-30 10:48:16 [SEVERE] Could not pass event CorrectAnswerEvent to TestqUiz
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:332)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at me.number1_Master.TestqUiz.Listeners.PlayerListener.onPlayerMove(PlayerListener.java:53)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:330)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:213)
at net.minecraft.server.Packet10Flying.handle(SourceFile:136)
at net.minecraft.server.NetworkManager.b(NetworkManager.java:276)
at net.minecraft.server.NetServerHandler.d(NetServerHandler.java:109)
at net.minecraft.server.ServerConnection.b(SourceFile:35)
at net.minecraft.server.DedicatedServerConnection.b(SourceFile:30)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:581)
at net.minecraft.server.DedicatedServer.q(DedicatedServer.java:212)
at net.minecraft.server.MinecraftServer.p(MinecraftServer.java:474)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:406)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)
Caused by: java.lang.NullPointerException
at me.number1_Master.TestqUiz.Listeners.CorrectListener.onCorrect(CorrectListener.java:26)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:330)
... 22 more

Now you may ask what lines 40 and 53 are. Well, those are the lines where I call my event.

What did I do wrong when calling my event?

 

number1_Master
Are you sure those listeners are listeners and not the actual custom event.

 

yup. They implement Listener, and the event they call is my custom event.

Thanks for the help! -_-

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Looking at line 550 of SimplePluginManager makes me think that the issue might be with the custom events you wrote (or at least, the custom event involved with the listener that is throwing errors when it is being registered).

 

At first, I got a handler error which was because I didn't have the getHandlerList() method.
Is it necessary to put @Override above these methods? I didn't see that on the wiki.

 

I'm guessing that it's probably just a small error with one of the events. I'm guessing this because it looks like the error is (if I understand) being thrown when you're registering the second listener (iListener), which means that ppListener (your first listener) and its custom are probably fine. So my thinking is that you have custom events that are fine, but one (at least) that has an error.

 

It occurs on all of the listeners. The reason why it occurred on the second listener in this situation is because I made the first one a comment.

 

Well darn; there goes that theory. I want to be more help, but I'm stuck away from my dev environment so I can't test anything.

 

I forgot to put a link to the source. Maybe you can look into it.

 

I think I'm mostly grasping at straws here, but the only thing that I noticed was that getHandlerList() is not static. I've noticed that it is in the wiki and in bukkit events. Will that fix the issue? (Grasping at straws...)

 

You could be right! Testing it right now.

You were right. Now I have a Vault error but I think I can fix it.

Thanks!

MucTweezer . Since you seem to know more about Events then I do, can you please help me with my second issue? Read the first post (I edited it).

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Code:

Caused by: java.lang.NullPointerException
at me.number1_Master.TestqUiz.Listeners.PreprocessListener.onPreprocess(PreprocessListener.java:23

Player seems to be null...

 

I missed that null pointer. I was only looking at the top of the error
hmm Then what is wrong here? Am I assigning player incorrectly?

Edit: Ya, I am assigning player incorrectly...

 

Haha, I'm not sure I'm all that knowledgeable about events, but hey, I try.

Based on Giant's comment, I compared your events again to bukkit events. I noticed that in BlockBreakEvent, player is declared final. Again, more grasping at straws, but I'm left with little else in the absence in my dev environment. However, maybe that will help?

 

You have lucky straws. Ima test it.

MucTweezer Giant
I set the player to final and flipped player = this.player to this.player = player. Well, I got this error:

Show Spoiler Hide Spoiler

Code:

11:36:40 [SEVERE] Could not pass event PlayerMoveEvent to TestqUiz
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:332)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:213)
at net.minecraft.server.Packet10Flying.handle(SourceFile:136)
at net.minecraft.server.NetworkManager.b(NetworkManager.java:276)
at net.minecraft.server.NetServerHandler.d(NetServerHandler.java:109)
at net.minecraft.server.ServerConnection.b(SourceFile:35)
at net.minecraft.server.DedicatedServerConnection.b(SourceFile:30)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:581)
at net.minecraft.server.DedicatedServer.q(DedicatedServer.java:212)
at net.minecraft.server.MinecraftServer.p(MinecraftServer.java:474)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:406)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)
Caused by: java.lang.NullPointerException
at me.number1_Master.TestqUiz.Listeners.PlayerListener.onPlayerMove(PlayerListener.java:69)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:330)
... 14 more

Line 69 ( ) is where I remove the player if he is cheating, but apparently there might be something wrong with the System.currentTimeMillis? Dunno. Looks like my preprocess is messed up (in a way). The good thing though is that the answers somewhat work.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

I'm thinking it has to do with TestqUiz.p.cheaters.get(player) instead of TestqUiz.p.cheaters.get(playerName).

 

I agree with MucTweezer you are kind of getting a "null" object now, which you then compare to System.currentTimeMillis....

 

Yup you people are right. I should be getting a string, not a player.

Thanks Giant and MucTweezer. You guys helped me a lot!

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Glad to have been of service!