blooker20@blooker20:/etc/phpmyadmin$ sudo journalctl -xe
[sudo] password for blooker20:
-- The result is RESULT.
Jul 24 13:00:55 blooker20 systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
Jul 24 13:00:55 blooker20 systemd[1]: mysql.service: Scheduled restart job, restart counter is at 23.
-- Subject: Automatic restarting of a unit has been scheduled
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Automatic restarting of the unit mysql.service has been scheduled, as the result for
-- the configured Restart= setting for the unit.
Jul 24 13:00:55 blooker20 systemd[1]: Stopped MySQL Community Server.
-- Subject: Unit mysql.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has finished shutting down.
Jul 24 13:00:55 blooker20 systemd[1]: Starting MySQL Community Server...
-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has begun starting up.
Jul 24 13:00:55 blooker20 audit[18307]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18307 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
Jul 24 13:00:55 blooker20 kernel: audit: type=1400 audit(1532430055.309:356): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18307 comm="mysqld" requested_mask="r" denied_mask="r" fsuid
Jul 24 13:00:55 blooker20 audit[18309]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18309 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=122 ouid=0
Jul 24 13:00:55 blooker20 kernel: audit: type=1400 audit(1532430055.357:357): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18309 comm="mysqld" requested_mask="r" denied_mask="r" fsuid
Jul 24 13:02:35 blooker20 mysqld[18309]: Initialization of mysqld failed: 0
Jul 24 13:02:35 blooker20 systemd[1]: mysql.service: Control process exited, code=exited status=1
Jul 24 13:02:35 blooker20 systemd[1]: mysql.service: Failed with result 'exit-code'.
Jul 24 13:02:35 blooker20 systemd[1]: Failed to start MySQL Community Server.
-- Subject: Unit mysql.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has failed.
--
-- The result is RESULT.
Jul 24 13:02:36 blooker20 systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
Jul 24 13:02:36 blooker20 systemd[1]: mysql.service: Scheduled restart job, restart counter is at 24.
-- Subject: Automatic restarting of a unit has been scheduled
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Automatic restarting of the unit mysql.service has been scheduled, as the result for
-- the configured Restart= setting for the unit.
Jul 24 13:02:36 blooker20 systemd[1]: Stopped MySQL Community Server.
-- Subject: Unit mysql.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has finished shutting down.
Jul 24 13:02:36 blooker20 systemd[1]: Starting MySQL Community Server...
-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has begun starting up.
Jul 24 13:02:36 blooker20 audit[18333]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18333 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
Jul 24 13:02:36 blooker20 kernel: audit: type=1400 audit(1532430156.055:358): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18333 comm="mysqld" requested_mask="r" denied_mask="r" fsuid
Jul 24 13:02:36 blooker20 audit[18335]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18335 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=122 ouid=0
Jul 24 13:02:36 blooker20 kernel: audit: type=1400 audit(1532430156.107:359): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=18335 comm="mysqld" requested_mask="r" denied_mask="r" fsuid
Jul 24 13:02:40 blooker20 sudo[18350]: pam_unix(sudo:auth): authentication failure; logname=blooker20 uid=1000 euid=0 tty=/dev/pts/0 ruser=blooker20 rhost= user=blooker20
Jul 24 13:02:42 blooker20 sudo[18350]: blooker20 : 1 incorrect password attempt ; TTY=pts/0 ; PWD=/etc/phpmyadmin ; USER=root ; COMMAND=/usr/sbin/service mysql startjournalctl -xe
Jul 24 13:02:55 blooker20 sudo[18353]: blooker20 : TTY=pts/0 ; PWD=/etc/phpmyadmin ; USER=root ; COMMAND=/bin/journalctl -xe
Jul 24 13:02:55 blooker20 sudo[18353]: pam_unix(sudo:session): session opened for user root by blooker20(uid=0)

.

blooker20@blooker20:/etc/phpmyadmin$ sudo systemctl status mysql.service
● mysql.service - MySQL Community Server
  Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
  Active: activating (start) since Tue 2018-07-24 13:04:17 CEST; 35s ago
 Process: 18359 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
 Main PID: 867 (code=exited, status=0/SUCCESS); Control PID: 18368 (mysqld)
  Tasks: 14 (limit: 4915)
  CGroup: /system.slice/mysql.service
      ├─18368 /usr/sbin/mysqld --daemonize --pid-file=/run/mysqld/mysqld.pid
      └─18370 /usr/sbin/mysqld --daemonize --pid-file=/run/mysqld/mysqld.pid

Jul 24 13:04:17 blooker20 systemd[1]: Starting MySQL Community Server...

Du hast doch bestimmt einen @EventHandler für das Klicken des Kompasses. Das PlayerInteractEvent hat das feld #getPlayer(), das den Spieler des Events zurückgibt. Mit event#getPlayer()#getInventory()#setSlot(int SlotNummer, new ItemStack(Material.AIR)) kannst du dann einen bestimmten Slot leeren. Eventuell speicherst du davor noch die Items mit event#getPlayer()#getInventory()#getItem(int SlotNummer).
Google ist dein Freund!

Das geht meines Wissens nach mit NMS. Back kurzem Googeln bin ich auf fogendes gestoßen

void noAI(Entity bukkitEntity) {
  net.minecraft.server.v1_8_R1.Entity nmsEntity = ((CraftEntity) bukkitEntity).getHandle();
  NBTTagCompound tag = nmsEntity.getNBTTag();
   if (tag == null) {
    tag = new NBTTagCompound();
   }
  nmsEntity.c(tag);
  tag.setInt("NoAI", 1);
  nmsEntity.f(tag);
}

Grundlegen ist Spawnern die Höhe egal

Naja, es wird ja einen Grund haben, dass der Command Player-Only ist. Wenn man zbsp. einen Commandblock einen Befehl ausführen lässt wo ein GUI geöffnet wird, dann läuft das Plugin nicht mehr(Solche Commands gibts in Vanilla nämlich nicht)

LG Blooker20