[21:43:36 WARN]: org.apache.commons.lang.UnhandledException: Plugin MobspawnSettings v1.1 generated an exception while executing task 4
        at org.bukkit.craftbukkit.v1_9_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoSuchMethodError: org.bukkit.Server.getOnlinePlayers()[Lorg/bukkit/entity/Player;
        at org.telamitto.sycoso.mobspawnsettings.MetricsLite.postPlugin(MetricsLite.java:285)
        at org.telamitto.sycoso.mobspawnsettings.MetricsLite.access$3(MetricsLite.java:278)
        at org.telamitto.sycoso.mobspawnsettings.MetricsLite$1.run(MetricsLite.java:173)
        at org.bukkit.craftbukkit.v1_9_R1.scheduler.CraftTask.run(CraftTask.java:53)
        at org.bukkit.craftbukkit.v1_9_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
        ... 3 more