Flying and aquatic mobs pathfinding in certain blocks cause crash || The game crashed whilst ticking entity Error: java.lang.NullPointerException: Cannot invoke "dnm.a()" because "$$1" is null

The Allay is what crashed my game and I can't reopen the world.Still affects 22W16B

I was able to reopen my world by deleting the "session.lock" file in the world save folder.

Still in 22w16b.

I deleted "session lock" and still crashes before opening.

Oh, yeah, it's definitely gonna keep crashing, but it solved the problem I was having of the world not showing up on the save list. You'd have to get rid of the allay to stop the crashing completely.

I have the same crash, but with "parrot" instead of allay, exactly as another user reported in MC-250350

I got my game to crash in 22w16b as well. Every time I fly to where the allay is in the crash report, my game crashes.

I have a kinda weird fix. Go to the save, then entities. Sort by date modified, then look at the properties of the files, if the file says created today, I deleted it. Do this for all files created near the time of the crash. Its worked for me but still I recommend backing up the whole save before doing this JUST IN CASE.

This happens when a mob is trying to pathfind inside a partially solid block, like a fence post or bed. So far, I've had it happen because a parrot was trying to fly inside a fencepost, a bed, and an alchemy stand. As long as they're sitting this wont happen, but if you have one sitting on the block an alchemy stand is on, for instance, and you let it stand up and try to fly off, the game will crash, and will continue to crash as soon as you load that save.

While this makes your save completely unusable, deleting your entities files like MINABEAN suggests will fix this, because it will delete the entity that was causing the issue; if that entity is an animal that you're trying to keep, it will be gone. I fixed this by using NBTExplorer to edit the position of the entity that caused the error. At worst, you could wait until they patch this.

Hey thanks MINABEAN, it worked! I can open that world again for now. I guess I'll have to keep this fix in mind until they fix the bug.

Same to me in 22w16b

I can confirm this happens to me too. in my case it's bees

My server is also crashing, and yep, it's a bee apparently.

Its crashing for me due to the Allay

Code analysis (yarn 22w16b):

PathNodeMaker#getPath(int, int, int) return value is nullable in some subclasses (notably the one used by bird-like mobs and aquatic mobs). LandPathNodeMaker#method_43415 calls getPath(BlockPos) which calls getPath(int, int, int).  Then it calls dnm.a / PathNode#getBlockPos() at line 109 thus causing NullPointerException.

can confirm in 22w16b

can confirm it happens in both singleplayer and multiplayer for Bees

ohh I thought I was the only one experiencing this

the last time I opened my world on last week's snapshot I was in an area near some bees and whenever I enter it on the latest one it keeps on crashing, and if I ever get in the game crashes a few seconds later

I've had this happen to me a few times, I have no idea why but loading in a bee crashes my game, and I crash on both single and multiplayer. I can get onto the world but past that I either crash in a few minutes or a couple seconds.

to help reproduce this bug:
I had this happen after a while having spawned in some Allays (around a dozen, one had an item) on top of a Ancient City portal construct, I stayed up there and they wandered down and off. I had tp'ed them all to me a few times to try to keep them closer.
I lost that save file completely. 22w16b. Maybe this will help reproduce. There was a Nether Portal not too far away, not sure if that would do it.
I don't have the error on me but it said it sent, and the crash error had to do with Allay code, prob pathfinding.
It gets worse with time, it's some kind of memory issue, the second load of the save file was fine for a few seconds.
On the 3rd and 4th it crashed so fast I couldn't paste run a command I made to kill all allays.

Woah I've been getting the same bug on the server side too. It occurs when the server suddenly shutdown for some reason that I doesnt know. Then I couldn't open the server anymore

Confirmed, fought a Wither underground, it crashed my game after it broke through a few blocks

tried on a different world, wither seemed to be more "jittery" when flying

my world crashed of bee with

bee's name: Пчела

here's what happened on my computer:

ime: 4/21/22, 11:38 AM
Description:

Ticking entity

java.lang.NullPointerException: Cannot invoke "dnm.a()" because "$$1" is null

 Entity being ticked –
Details:
    Entity Type: minecraft:bee (bks)
    Entity ID: 132
    Entity Name: Пчела
    Entity's Exact location: -151.03, 78.00, 557.03
    Entity's Block location: World: (-152,78,557), Section: (at 8,14,13 in -10,4,34; chunk contains blocks -160,-64,544 to -145,319,559), Region: (-1,1; contains chunks -32,32 to -1,63, blocks -512,-64,512 to -1,319,1023)
    Entity's Momentum: 0.00, 0.00, 0.00
    Entity's Passengers: []
    Entity's Vehicle: null

If u delete the entitie folder, you are able to restart your game but ofc u have no more entitie in your game 

i have the same problem

Can confirm same error, when using natural spawned allays, not from spawn eggs however

"Ticking entity

java.lang.NullPointerException: Cannot invoke "dnm.a()" because "$$1" is null"

Same here. Happened first on an Aternos server with some armor stand. When I exported the world back into single player, it blamed it on allays. I'm not sure if armor stands have pathfinding, but fix this ASAP anyways, I've put too much effort into that world for it to go to waste.

Can confirm. I made a wolrd with an allay named Aleia. I got on and it was working right, but I brought her outside and she'd wander far away from me. When I brought her down to my boat dock, the game crashed. (it marks her as the reason for crash) i can't open the world now. 😞

just happened on a completely vanilla 22w16b server that had been online for not less than 16 hours, all users logged off, except one.  nothing else in the event logs after that until the crash.  Server shutdown gracefully after crash and will NOT relaunch.

I did get it back online, but it only stayed up for 13 hours this time.  Pretty sure I know the cause based off the info here.  One of the players setup a guardian farm out in the ocean.  I did not think that was the issue the first time as the only person online was no where near it, so it should have been unloaded chunks

Game boots normally, try to play a world that had the previous snapshot to 22w16b and I get :-

The game crashed whilst ticking entity
Error: java.lang.NullPointerException: Cannot invoke "dnm.a()" because "$$1" is null
Exit Code: -1

Hoping for a resolution soon! 😃

Also experienced this crash while running around a newly generated creative world, uploaded a crash report

Game crashes almost instantly after re-opening that world.

I opened the world twice then, I reopened that world a few minutes later and it didn't occur

Also just ran into this crash in the latest snapshot, same as everyone else's it seems; caused by an Allay in a woodland mansion when I loaded said mansion in by leaving spectator mode and entering creative. I've uploaded the crash report.

I had the same crash 2 times.

The first one happened when I switched to creative mode and spawned some bees, the game froze for 1 second and after that my desktop popped up,
And the second crash happened while opening a world.

Please note that "me too" comments are not helpful if they don't add any new information to the report.

You can use the "Vote for this issue" function to show that you're affected by this bug 🙂

Way to reproduce:

With 22w16b, create new world with seed -2659154492389595023 and default settings. From spawn point, locate mansion (should be at 2960, ~, -3616). Teleport there, walk around a bit. In my test session, the crash occured when the player was close to the mansion entrance.

Well it's maybe me also kind of comment, but i will try to say exacly what's happening. I few days ago opened my world in 22w16b snapshot to be greeted by super lagy behavior and then poof, it's gone, my world crumbled, as in error -1 entity ticking type bee ant coordinates 600 something - 400 something, within my honey block and wax farm. I happened everytime i opened world from then on, withing few secounds of world beeing loaded, im at least two chunks away from the farm and im not expert so i did just the obvious and obviously futile things like animation distance 5 chunks, render distance 2 chunks, same result, i have 5 active beacons ubove my head but idk if that is to blame, anyway im not fast enough to kill the bees or disable beacons, i put on peacefull mode and it still crashed all the same with just error -1 no description this time. Could be just pathfinding or maybe more problems just the ticking entity kills the game first.

My "gaming" rig or set or whatever you can call this is a laptop with i7 8Gb RAM, 1 TB hybrid HDD +8GB SSD , and geforce gt 745M, windows 8.1, 17.6",first restore point dated at 2014, i might have misspelled something. 

As @unknown stated, please only add a comment if you have new information to add to the report. The cause of the issue is already known, and there are several crash reports attached to this ticket. Please be considerate of adding comments, as every message is sent to every watcher's e-mail.

If you guys have a problem with this bug on your worlds, you should use NBTexplorer to change coordinates of player. I know it can be called as form of cheating, but there are no other ways to use world again before snapshot with bugfix

Just had this bug as well! The issue seemed to happen after I made a mangrove tree with /placefeature and used the command "/fill ~-10 ~-10 ~-10 ~10 ~10 ~10 air replace #leaves" and "/fill ~-10 ~-10 ~-10 ~10 ~10 ~10 air replace #logs". Happened within less than a second of me using these commands and then breaking the mangrove propagule that I had placed down. Not sure if these are directly correlated, but it sure seemed that way to me

For those needing access to worlds which have been disabled by this bug while we await a patch, I have found several quick fixes, they all work on the same principle; that you have a moment to teleport far from the area before the entity begins any pathfinding. As soon as your game loads, teleport to a location known to be far from this entity. The position of the entity is included in the crash report, so just refer to this position and teleport at least a few hundred blocks away. This has worked for me in every case thus far, so hopefully it works for at least most of you, provided that the entity was not within the permanently loaded spawn chunks - (but even if that is the case, one would just need to involve an extra step of temporarily changing the world spawn location via /setworldspawn - just change it temporarily to the same distant position you teleported to)
Once you have safely teleported away from the entity, and you are no longer crashing, you have several options:
1.) If the area doesn't matter, but the mob does - just avoid the area until this issue is patched. but this is difficult, as this crash can get you from many chunks away, and it does not matter which player wanders into the zone of death, all players will crash.
2.) If you need the area to be accessible, and the mob does not matter much to you, what you want to do is place a repeating command block within the spawn chunks, and issue the command " /execute at @p run kill entity @e[type=bee, distance=0..10] " (presuming it is a bee, edit mob type according to your crash report) and then refer to your crash report for the entity's location. With this command block active within the spawn chunks, bravely teleport yourself directly to the location of the problem entity via /tp X Y Z. The speed of the command block issuing the order to kill the problem entity is fast enough to kill the entity before it can fire off any pathfinding. I've witnessed the deaths of many poor bees and parrots in this manner over the past few days. Make sure to destroy your command block when done, or you will continue to autokill all bees/parrots/whatever within 10 blocks of you as you travel throughout your world, like some sort of reaper of flying mobs.

Congrats, you have now quick fixed your world until the next bee or parrot tries to fly into a fence post. Hope this is helpful to anyone feeling locked out of their worlds due to this bug.

As a quick fix, whenever it happens I just use NBTExplorer and the crash log to find the offending bee and teleport it 15 blocks up. It's the least cheaty way of resolving the issue afaik and has no lasting effects under most circumstances (other than letting you back into your world). Hope it helps someone

The crash report will have a header titled "-- Entity being ticked–"
Under "Details:", there's a value "Entity's Block location". It's a bit of a mess, but what you want are "Region", "Section", and "World", in that order. If you go into NBTExplorer and open the entities folder in the root of your save file, you'll see a bunch of entries titled like "r.-1.-1.mca". You'll want whatever shows up at the very beginning of the "Region" heading in the crash report. Within that, you'll see a bunch of files for the individual chunks. In "Section" it starts of "at x,y,z in x1,y1,z1". What you want are x1 and z1, those are the chunk coords and what you're actually looking for. Then, go through all the entities in that chunk and find the one that A) has the same id as the offending party (the first thing I check for cuz it's faster), and B) is at the same position ("Pos" tag).

Set its Y coord (the center one) to something like 15 blocks higher than it currently is, and you should be able to load back in fine!

As a note, you'll continue to have these issues and have to resolve it the same way every time if you hang around the area, so depending on your preferences you may prefer just killing them (or wiping them straight from the face of the earth, pretty certain just deleting them in nbtexplorer would do as such)

Sometimes minecraft crashes without information in the launcher, only exit code -1 if you follow the "How to reproduce" steps in my Bugreport: MC250673