Sorry for the misunderstanding.
If you use Lightstreamer SDK for Java Remote Adapters, the SDK library produces some log and there are instructions on how to configure the verbosity and the log file.
You can find the relevant information in the javadocs for SDK version 1.3.1
https://lightstreamer.com/docs/ls-se...nce/index.html
(see setLoggerProvider)

I'm not sure that this is what you expected.
If you want a facility to write to a file the log produced by your code, this is not provided, but it is the other way round.
In fact, the library doesn't provide a log implementation, but requires that the hosting program provides such implementation for its own log.
In this way, the hosting program can implement a bridge to send the log produced by the library to this implementation.

We show the full process in the examples. See this one.
Look in particular for the custom OutPrintLog class and its uses. Unfortunately, the example is simple and just sends the log to the standard output. To send the log to an implementation like log4j, more custom code is needed.

Please be aware that this matter has undergone a few changes in the latest 1.4.0 version of the SDK, hence, when you upgrade the SDK, a small code change will be needed.