NullPointerException

I'm currently making a plugin, but I've come across an NPE:

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Code:

[12:46:15 WARN]: java.lang.NullPointerException
[12:46:15 WARN]:        at me.genki.ms.JoinGui.onPlayerJoin(JoinGui.java:28)
[12:46:15 WARN]:        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native M
ethod)
[12:46:15 WARN]:        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown S
ource)
[12:46:15 WARN]:        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unkno
wn Source)
[12:46:15 WARN]:        at java.lang.reflect.Method.invoke(Unknown Source)
[12:46:15 WARN]:        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(Jav
aPluginLoader.java:292)
[12:46:15 WARN]:        at org.bukkit.plugin.RegisteredListener.callEvent(Regist
eredListener.java:62)
[12:46:15 WARN]:        at org.bukkit.plugin.SimplePluginManager.fireEvent(Simpl
ePluginManager.java:501)
[12:46:15 WARN]:        at org.bukkit.plugin.SimplePluginManager.callEvent(Simpl
ePluginManager.java:486)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.PlayerList.c(PlayerList.
java:229)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.PlayerList.a(PlayerList.
java:116)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.LoginListener.c(LoginLis
tener.java:78)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.LoginListener.a(LoginLis
tener.java:42)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.NetworkManager.a(Network
Manager.java:150)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.ServerConnection.c(Sourc
eFile:134)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.MinecraftServer.v(Minecr
aftServer.java:657)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.DedicatedServer.v(Dedica
tedServer.java:250)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.MinecraftServer.u(Minecr
aftServer.java:548)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.MinecraftServer.run(Mine
craftServer.java:459)
[12:46:15 WARN]:        at net.minecraft.server.v1_7_R2.ThreadServerApplication.
run(SourceFile:618)

JoinGui Method:

Code:java

try{
        for(int x = 1 ; x > 0; x++) {
 
            if(ms.c1(x) == null){ // <-- Line 28 
                ms.c2("p." + x, pu);
                p.sendMessage("Added");
                break;
            } else {
                continue;
            }
        }
        } catch (Exception e) {
            e.printStackTrace();
        }

Main Class:

Code:java

public String c1(int x){
 
        String s = config.getString("p." + x);
        return s;
 
    }
 
    public void c2(String s, String a){
        config.set(s, a);
    }

I'm not sure what I am doing wrong...

 

"ms" is null. Also, your for loop is infinite (some number is one, as long as some number is greater than 0, increment some number). Well, I suppose it will terminate when the int overflows to Integer.MIN_VALUE. But that's no way to do loop.

 

TeeePeee It will not infinitely loop as the loop breaks if it gets to a point. Anyway this is fixed.

 

FlareLine
Oops, never saw the break on my glance. Just read the for parameters and line 28. Sorry!