Bukkit

Hi, I would like to ask you if you know, why is this error popping up?

[2K [13:56:37 WARN]: Exception in thread "Craft Scheduler Thread - 2070"
> [13:56:37 WARN]: org.apache.commons.lang.UnhandledException: Plugin ChunkSpawnerLimiter v3.0.0 generated an exception while executing task 2016
at org.bukkit.craftbukkit.v1_10_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NoSuchMethodError: org.bukkit.Server.getOnlinePlayers()[Lorg/bukkit/entity/Player;
at org.mcstats.Metrics.postPlugin(Metrics.java:357)
at org.mcstats.Metrics.access$4(Metrics.java:350)
at org.mcstats.Metrics$1.run(Metrics.java:245)
at org.bukkit.craftbukkit.v1_10_R1.scheduler.CraftTask.run(CraftTask.java:71)
at org.bukkit.craftbukkit.v1_10_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
... 3 more