[MC-38051] "Couldn't process command" error in server log when no players connected

If a command block on a clock running a command similar to

/tp @r[x,y,z,r] x y z

exists in a world on a multiplayer server, when there are no players connected to the server, the server console is spammed with this error:

[timestamp] [Server thread/ERROR]: Couldn't process command
java.lang.NullPointerException
        at java.util.Collections.shuffle(Collections.java:497) ~[?:1.7.0_45]
        at java.util.Collections.shuffle(Collections.java:469) ~[?:1.7.0_45]
        at ad.c(SourceFile:127) ~[minecraft_server.1.7.2.jar:?]
        at ad.a(SourceFile:44) ~[minecraft_server.1.7.2.jar:?]
        at y.d(SourceFile:114) ~[minecraft_server.1.7.2.jar:?]
        at bu.b(SourceFile:33) ~[minecraft_server.1.7.2.jar:?]
        at z.a(SourceFile:58) [minecraft_server.1.7.2.jar:?]
        at afb.a(SourceFile:79) [minecraft_server.1.7.2.jar:?]
        at ain.a(SourceFile:49) [minecraft_server.1.7.2.jar:?]
        at mj.a(SourceFile:405) [minecraft_server.1.7.2.jar:?]
        at mj.b(SourceFile:134) [minecraft_server.1.7.2.jar:?]
        at net.minecraft.server.MinecraftServer.u(SourceFile:503) [minecraft_server.1.7.2.jar:?]
        at lj.u(SourceFile:265) [minecraft_server.1.7.2.jar:?]
        at net.minecraft.server.MinecraftServer.t(SourceFile:441) [minecraft_server.1.7.2.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:358) [minecraft_server.1.7.2.jar:?]
        at ky.run(SourceFile:617) [minecraft_server.1.7.2.jar:?]

As soon as a player connects this stops.

edit: simplification

Comments 5

Matthew Hamilton 2013-12-18T23:40:25Z

This is also an issue I have came across therefore I'm assuming this is an issue with the vanilla minecraft server in general. This issue occurs when the server is empty as well.

My environment: OS: Windows 8.1 running Java 1.7.0_45

A screenshot: https://twitter.com/MGH7531/status/413432399188332544

Talven81 2013-12-19T00:21:05Z

While this shouldn't happen, if you are looking for a temporary workaround try using a testfor command block with comparator output to the TP command block.

David Robertson 2014-02-18T16:38:09Z

This does not seem to affect 14w07a, but I did not test previous snapshot versions.

galaxy_2alex 2014-10-30T19:52:51Z

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases. If this has been done, we can reopen the issue.

Keep in mind that the "Resolved"-Status on this ticket just means "Answered", and that we are waiting for further information on whether this issue still exists or not. We will reopen it as soon as the requested information has been deliviered.

user-f2760 2016-03-23T08:58:29Z

This ticket is incomplete without the requested information, no response has been received within a reasonable time and we are assuming the issue has been resolved. If you are still experiencing this issue, we can reopen it at your request.
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