这个异常在 packet.scala 的第 36 行（return 语句）抛出，这个 lambda 在第 53 行被 Side.handlePacket 调用。
完整日志：
[INFO|2017-02-07 19:43:25|main] Intermediary starting up…
[INFO|2017-02-07 19:43:25|Dispatcher Thread] Listening on port 31102
[INFO|2017-02-07 19:43:25|main] Registered packet deserializer for packet 00 for side Server
[INFO|2017-02-07 19:43:25|main] Registered packet class common.net.packet.PacketTest for side Server
[INFO|2017-02-07 19:43:28|Dispatcher Thread] Queued connection /127.0.0.1:57026
[INFO|2017-02-07 19:43:28|Connection Thread 0] New connection: /127.0.0.1:57026
[DEBUG|2017-02-07 19:43:28|Connection Thread 0] New packet handler for class class common.net.packet.PacketTest!
[DEBUG|2017-02-07 19:43:28|Connection Thread 0] New packet of size 5
[INFO|2017-02-07 19:43:28|Connection …scala ×1