[I] [Bug]: SerialSocketChannel does not properly close itself

["zawodskoj (via GitHub)" <gi...@apache.org>]

zawodskoj opened a new issue, #1342:
URL: https://github.com/apache/plc4x/issues/1342

   ### What happened?
   
   For some reason, if `Bootstrap.connect(...)` had failed for any reason, EventLoopGroup.shutdownGracefullly does not close channel and keeps `select`-ing it indefinitely, causing a lot of logs to appear
   
   ```
   NioEventLoop -- Selector.select() returned prematurely 512 times in a row; rebuilding Selector org.apache.plc4x.java.transport.serial.SerialPollingSelector@5bb67f2.
   NioEventLoop -- Migrated 1 channel(s) to the new Selector.
   NioEventLoop -- Selector.select() returned prematurely 512 times in a row; rebuilding Selector org.apache.plc4x.java.transport.serial.SerialPollingSelector@4a67eb86.
   NioEventLoop -- Migrated 1 channel(s) to the new Selector.
   NioEventLoop -- Selector.select() returned prematurely 512 times in a row; rebuilding Selector org.apache.plc4x.java.transport.serial.SerialPollingSelector@748a37b5.
   NioEventLoop -- Migrated 1 channel(s) to the new Selector.
   ```
   
   There is a basic repro - it purposely tries to open non-existent serial port and fails: https://gist.github.com/zawodskoj/68987f535bbfe199eeee9be43cf4bf13
   
   There is also a dirty workaround - it is possible to obtain SerialPollingSelector through reflection and invoke `close()` on them, catching meaningless NotImplementedException
   
   ```kotlin
   val getJCh = AbstractNioChannel::class.java.getDeclaredMethod("javaChannel")
   getJCh.isAccessible = true
   val javach = getJCh.invoke(cch) as AbstractInterruptibleChannel
   try {
       javach.close()
   } catch (e: NotImplementedException) {
       // ???
   }
   ```
   
   Soon after another `rebuildSelector0()`, Netty attempts to re-register channel, fails to do so (because it is already closed) and exits the infinite loop
   
   ```
   WARN  io.netty.channel.nio.NioEventLoop -- Selector.select() returned prematurely 512 times in a row; rebuilding Selector org.apache.plc4x.java.transport.serial.SerialPollingSelector@287d3f58.
   WARN  io.netty.channel.nio.NioEventLoop -- Failed to re-register a Channel to the new Selector.
   java.nio.channels.ClosedChannelException: null
   	at java.base/java.nio.channels.spi.AbstractSelectableChannel.register(AbstractSelectableChannel.java:222)
   	at io.netty.channel.nio.NioEventLoop.rebuildSelector0(NioEventLoop.java:467)
   	at io.netty.channel.nio.NioEventLoop.rebuildSelector(NioEventLoop.java:368)
   	at io.netty.channel.nio.NioEventLoop.unexpectedSelectorWakeup(NioEventLoop.java:630)
   	at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:578)
   	at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997)
   	at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
   	at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
   	at java.base/java.lang.Thread.run(Thread.java:840)
   INFO  io.netty.channel.nio.NioEventLoop -- Migrated 0 channel(s) to the new Selector.
   ```
   
   ### Version
   
   v0.11.0
   
   ### Programming Languages
   
   - [X] plc4j
   - [ ] plc4go
   - [ ] plc4c
   - [ ] plc4net
   
   ### Protocols
   
   - [ ] AB-Ethernet
   - [ ] ADS /AMS
   - [ ] BACnet/IP
   - [ ] CANopen
   - [ ] DeltaV
   - [ ] DF1
   - [ ] EtherNet/IP
   - [ ] Firmata
   - [ ] KNXnet/IP
   - [ ] Modbus
   - [ ] OPC-UA
   - [ ] S7


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