Solved Weird NPE while registering events

Hello all, I am currently developing a UHC plugin which will have its custom API to add custom Scenarios.
Developers will be able to register their custom Scenarios.
I have created 2 Custom Events called ScenarioEnableEvent and ScenarioDisableEvent, which register and unregister the Listeners of the Custom Scenarios when they're enabled / disabled.
I've created a seperate class which implements Listener, that listens to those two events.
Whenever I try to register it it throws an NPE and I have no idea why (I already checked, plugin is not null)

My onEnable:

Code:

@Override
    public void onEnable() {
    scatter = new Scatter(this);
    timer = new Timer(this, false);
    scenarioRegistry = new ScenarioRegistry(this);
    worldManager = new UHCWorldManager(this);

    scenarios = new ScenarioGUI(this, scenarioRegistry);
    settings = new SettingsGUI(this, 27, "§aSettings");
    ccSettings = new CCSettingsGUI(this, 3 * 9, "§cCutclean Settings");

    scenarioRegistry.registerScenario(new ScenarioBestPVE("BestPVE", "1.0", "shawlaf"));

    Bukkit.getPluginManager().registerEvents(new UHCListener(this), this);
    new ScenarioListener(this); // Line 60
    }

ScenarioListener class:

Code:

public class ScenarioListener implements Listener {

    private UHC plugin;

    public ScenarioListener(UHC plugin) {
    this.plugin = plugin;
    Bukkit.getPluginManager().registerEvents(this, plugin); // Line 19
    }

    @EventHandler
    public void onScenarioEnable(ScenarioEnableEvent e) {
    if (e.getScenario().getListener() == null)
       return;

    Listener listener = e.getScenario().getListener();
    Bukkit.getPluginManager().registerEvents(listener, plugin);
    }

    @EventHandler
    public void onScenarioDisable(ScenarioDisableEvent e) {
    if (e.getScenario().getListener() == null)
       return;

    Listener listener = e.getScenario().getListener();
    HandlerList.unregisterAll(listener);
    }

}

Stacktrace:

Code:

[15:00:34 ERROR]: Error occurred while enabling ShawlafsUHC v1.0 (Is it up to da
te?)
org.bukkit.plugin.IllegalPluginAccessException: java.lang.NullPointerException
        at org.bukkit.plugin.SimplePluginManager.getEventListeners(SimplePluginM
anager.java:571) ~[bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.plugin.SimplePluginManager.registerEvents(SimplePluginMana
ger.java:527) ~[bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at me.shawlaf.uhc.scenario.ScenarioListener.<init>(ScenarioListener.java
:19) ~[?:?]
        at me.shawlaf.uhc.UHC.onEnable(UHC.java:60) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316) ~[b
ukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader
.java:324) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManage
r.java:404) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugin(CraftServer.jav
a:455) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.enablePlugins(CraftServer.
java:389) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.reload(CraftServer.java:83
9) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.Bukkit.reload(Bukkit.java:303) [bukkit.jar:git-Bukkit-1.7.
9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:
23) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:18
0) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.dispatchCommand(CraftServe
r.java:740) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.dispatchServerCommand(Craf
tServer.java:726) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at net.minecraft.server.v1_7_R4.DedicatedServer.aB(DedicatedServer.java:
294) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at net.minecraft.server.v1_7_R4.DedicatedServer.v(DedicatedServer.java:2
59) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:5
58) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java
:469) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]
        at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:6
28) [bukkit.jar:git-Bukkit-1.7.9-R0.2-16-g37c7969-b3105jnks]

Thanks in advance

 

In the ScenarioListeners constructor, use UHC as the argument, not Plugin

 

Still throwing an Exception :/

 

Try to replace this:

Code:

 if (e.getScenario().getListener() == null)
       return;

    Listener listener = e.getScenario().getListener();
    HandlerList.unregisterAll(listener);

with this:

Code:

HandlerList.unregisterAll(this);

And

Code:

public ScenarioListener(UHC plugin) {
    this.plugin = plugin;
    Bukkit.getPluginManager().registerEvents(this, plugin); // Line 19
    }

    @EventHandler
    public void onScenarioEnable(ScenarioEnableEvent e) {
    if (e.getScenario().getListener() == null)
       return;

    Listener listener = e.getScenario().getListener();
    Bukkit.getPluginManager().registerEvents(listener, plugin);
    }

You cannot register the events two times.

 

scenario.getListener() is NOT ScenarioListener


Edit:
I forgot to make getHandlerList() static in my custom event class, I'm so dumb .-.
ISSUE HAS BEEN SOLVED

 

Just saying, your class implements Listener...

 

scenario.getListener() and ScenarioListener are both Listeners, you're right
ScenarioListener listens to ScenarioEnableEvent and ScenarioDisableEvent and registers scenario.getListener()
scenario.getListener() is a listener that developers have to specify (it can be null, if it is null, it will be ignored) in order for the scenario's feautures to work

for example:
A BestPVE Scenario Listener would have to listen to EntityDamageEvent and EntityDeathEvent