`UncheckedIOException: SocketException: Socket closed` reported on shutdown

[hubertp]

Every shutdown of the app ends with

java.io.UncheckedIOException: java.net.SocketException: Socket closed
java.io.UncheckedIOException: java.net.SocketException: Socket closed

Needs further investigation on the source of it.

[JaroslavTulach]

My hypothesis: this is from ydoc-polyfill. When the application is closing we close various subsystems one after another. Possibly Helidon websocket implementation is closed, that generates a callback into WebSocket emulation and that prints a warning. Or some like that. Mostly harmless I guess.

[JaroslavTulach]

• I can still see those exceptions when closing a project
• they have no stack trace
  • possibly Logging from the other JVM delegates to the primary JVM #14788 might help us reveal the stack trace
• anyway, the hypothesis remains

[JaroslavTulach]

Maybe we can lower the logging level to INFO or less and then the exception disappears from the logs?