private static void checkAccess() { StackTraceElement[] cause = Thread.currentThread().getStackTrace(); String callingClass = cause.length > 2 ? cause[3].getClassName() : "none"; String callingParent = cause.length > 3 ? cause[4].getClassName() : "none"; // FML is allowed to call system exit and the Minecraft applet (from the quit button), and the dedicated server (from itself) if (!(callingClass.startsWith("cpw.mods.fml.") || ("net.minecraft.client.Minecraft".equals(callingClass) && "net.minecraft.client.Minecraft".equals(callingParent)) || ("net.minecraft.server.dedicated.DedicatedServer".equals(callingClass) && "net.minecraft.server.MinecraftServer".equals(callingParent))) ) { throw new ExitTrappedException(); } }