Getting Entry from an hashmap

Hey guys! I have got an Hashmap:

Code:

public HashMap<String, String> motds = new HashMap<String, String>();

and I add the folowing things to it:

Code:

motds.put("one", "1");
        motds.put("two", "2");
        motds.put("three", "3");

Now I have an Scheduler that writes every object of the HashMap in the chat (write->wait some ticks.->write...), no matter in what order.

Code:

public void time(){
       
       
       
        Bukkit.getScheduler().scheduleSyncRepeatingTask(this, new Runnable(){
            int t = 1;
           
           
           
            public void run(){
                if(t == motds.size()){
                    String s = motds.values().toArray()[motds.size()].toString();
                    Bukkit.getServer().broadcastMessage(s);
                    t = 1;
                   
                }else{
                    String s = motds.values().toArray()[t].toString();
                    Bukkit.getServer().broadcastMessage(s);
                    t++;
                   
                }
               
               
            }
           
           
        }, 40, 20*intcfg);
    }

Everything works fine, and it writes the first two entrys in the chat. But as soon as it reaches the if(t == motds.size()) I get the following error in the console:

Code:

[17:14:42 WARN]: [CUNNotify] Task #1801 for CUNNotify va0.1 generated an exception
java.lang.ArrayIndexOutOfBoundsException: 3
        at me.thruzzd.cunnotice.Main$1.run(Main.java:63) ~[?:?]
        at org.bukkit.craftbukkit.v1_9_R1.scheduler.CraftTask.run(CraftTask.java:71) ~[spigot_server.jar:git-Spigot-2038f4a-cd36f6f]
        at org.bukkit.craftbukkit.v1_9_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:350) [spigot_server.jar:git-Spigot-2038f4a-cd36f6f]
        at net.minecraft.server.v1_9_R1.MinecraftServer.D(MinecraftServer.java:729) [spigot_server.jar:git-Spigot-2038f4a-cd36f6f]
        at net.minecraft.server.v1_9_R1.DedicatedServer.D(DedicatedServer.java:400) [spigot_server.jar:git-Spigot-2038f4a-cd36f6f]
        at net.minecraft.server.v1_9_R1.MinecraftServer.C(MinecraftServer.java:660) [spigot_server.jar:git-Spigot-2038f4a-cd36f6f]
        at net.minecraft.server.v1_9_R1.MinecraftServer.run(MinecraftServer.java:559) [spigot_server.jar:git-Spigot-2038f4a-cd36f6f]
        at java.lang.Thread.run(Unknown Source) [?:1.7.0_79]

Why? And how can I fix it?

Thanks!

 

Here is an example array with a size of 3:
{ object 1, object 2, object 3 }

How to access it:
array[0] array[1] array[2]

Notice something? There is no array[3] because that would be the 4th element (doesn't exist -> error).

Use ++t mixed with remainder operator (%). That ensures that if the index t is bigger than the Collection's size, it begins from 0 again.

Example:

Code:

int i = 0;
while (1) {
    System.out.print(i + ", ");
    i = ++i %3;
}

Output: 0, 1, 2, 0, 1, 2, etc...
Why ++i and not i++ ? Here's the answer

@Zombie_Striker A even more efficent way to achieve what you want is the following :

Code:

int t = 0;

public void run() {
   String s = motds.values().toArray()[t].toString();
   Bukkit.broadcastMessage(s);
   t = ++t %motds.size();
}

Comparison to original code inside run(): 13 lines. My code: 3 lines

Why do you use Bukkit.getServer().method() ? Useless. Bukkit.method() is the same.

 

@ThrustLP
That is because you forgot .size != the last indxed. The method ".size()" returns the index +1, because it's first value is 1, while the first value for the index is 0.

To fix this, don't even check if it is equal to the size. A more efficent way to achieve what you want is the following:

Code:

int t = 0; //IT MUST BE 0, BECAUSE THE FIRST INDEX IS 0.        

public void run(){
 if(t == motds.size()){
  //If t is out of bounds
  t=0;//Set it back to 0.
}
String s = motds.values().toArray()[t].toString();
Bukkit.getServer().broadcastMessage(s);
t++;  
}