Error occurred while enabling MagicSpells v3.3-release (Is it up to date?)

java.lang.NoSuchMethodError: org/bukkit/Bukkit.getOnlinePlayers()[Lorg/bukkit/entity/Player; (loaded from file:/pro/bin/mc/craftbukkit/1.10.2/craftbukkit-1.10.2.jar by sun.misc.Launcher$AppClassLoader@6b154ee2) called from class com.nisovin.magicspells.LifeLengthTracker (loaded from file:/home/gs-41425/plugins/MagicSpells%20(2).jar by org.bukkit.plugin.java.PluginClassLoader@f842b56b).