Plugman 2.1.4

[Craft Scheduler Thread - 1188/WARN]: [PlugMan] Plugin PlugMan v1.8.1 generated an exception while executing task 27
java.lang.NoSuchMethodError: org.bukkit.Server.getOnlinePlayers()[Lorg/bukkit/entity/Player;
    at com.ryanclancy000.plugman.utilities.MetricsLite.postPlugin(MetricsLite.java:261) ~[PlugMan.jar:?]
    at com.ryanclancy000.plugman.utilities.MetricsLite.access$300(MetricsLite.java:48) ~[PlugMan.jar:?]
    at com.ryanclancy000.plugman.utilities.MetricsLite$1.run(MetricsLite.java:153) ~[PlugMan.jar:?]
    at org.bukkit.craftbukkit.v1_12_R1.scheduler.CraftTask.run(CraftTask.java:76) ~[spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at org.bukkit.craftbukkit.v1_12_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:52) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_161]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_161]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_161]