[MC-68381] NullPointerException: group when connecting to MP server

When I look at my multiplayer server, it says "Can't connect to server". I can ping it just fine (192.168.1.150), it's a local machine so I don't need to open any ports. It worked on the previous snapshot. I try doing a direct connect to 192.168.1.150, and I get "NullPointerException: group".

My log file shows this:

[22:26:34] [Client thread/INFO]: Connecting to 192.168.1.150, 25565
[22:26:34] [Server Connector #1/ERROR]: Couldn't connect to server
java.lang.NullPointerException: group
	at io.netty.bootstrap.AbstractBootstrap.group(AbstractBootstrap.java:79) ~[netty-all-4.0.15.Final.jar:4.0.15.Final]
	at gr.a(SourceFile:220) ~[14w34c.jar:?]
	at bvx.run(SourceFile:59) [14w34c.jar:?]