Spigot 1.8 - Hidendra/Plugin-Metrics GitHub Wiki

If you are seeing exceptions such as:

[20:09:00] [Craft Scheduler Thread - 0/WARN]: org.apache.commons.lang.UnhandledException: Plugin Vault v1.4.1-b436 generated an exception while executing task 3
at org.bukkit.craftbukkit.v1_8_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:57)
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 net.milkbowl.vault.Metrics.postPlugin(Metrics.java:387)
at net.milkbowl.vault.Metrics.access$400(Metrics.java:63)
at net.milkbowl.vault.Metrics$4.run(Metrics.java:275)
at org.bukkit.craftbukkit.v1_8_R1.scheduler.CraftTask.run(CraftTask.java:71)
at org.bukkit.craftbukkit.v1_8_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
... 3 more

You must update to metrics R8-SNAPSHOT. If you aren't using maven, it is available on the main source tree.