hi, i am using IntelliJ. I have a `fun main()...` ...

# getting-started

[edhu]

hi, i am using IntelliJ. I have a fun main()... function that I execute. when I execute the main function, the program runs, but I know there are exceptions being thrown by my code but none get outputted to my console. How can I setup logging so that I can see the logs in the console?

[fred.deschenes]

Well it depends on where those exceptions are thrown and what logging framework you use

[edhu]

Hi,i'm using:

io.github.microutils:kotlin-logging:1.4.9

if i log statements in my project, it works. but the exceptions being thrown from a Jar dependency that i call do not get shown in the console

[edhu]

all i see is Process finished with exit code 0

[fred.deschenes]

you'll have to check what logging framework this dependency uses and probably change some configs on your side to have their loggers show up in your log files/IDE (I've never used kotlin-logging so I don't really know how it works)

[fred.deschenes]

what's your dependency that's throwing the exception?

[edhu]

my own jar file

[edhu]

in my own jar file, i added:
compile 'org.slf4j:slf4j-api:1.7.10'

[edhu]

i read that for libraries, i only have to add that dependency

[fred.deschenes]

yeah but you still have to log whatever you want logged yourself

[edhu]

the exception not being logged is a NPE because some models are not marked as nullable

[edhu]

i'm an Android developer, and I'm used to every error is shown in the console

[edhu]

i guess it is a system exception, Kotlin telling me a property is not set as nullable

[fred.deschenes]

yeah NPEs are RuntimeExceptions

[edhu]

what can i do to show all these errors in the console?

[fred.deschenes]

either way, you won't see exceptions show up in the console if they aren't :
1: thrown in the main thread
2: explicitly logged in some logging framework

[fred.deschenes]

so you'd have to get a logger from SLF4J, wrap whatever is throwing your exception in a try/catch and do logger.error(...) with your caught exception

[edhu]

ok, so i run the code and on a breakpoint before the NPE i can see : "ForkJoinPool.commonPool-worker-1" in group "main" : RUNNING

[edhu]

so it is in the main thread

[edhu]

i just wrapped the call in a try catch but nothing is shown

[fred.deschenes]

if your thread name is "ForkJoinPool.commonPool-worker-1" you're definitely not in the main thread

[fred.deschenes]

either way I suggest you read a bit on how SLF4J works as you'll have other stuff to setup to make sure your logs are displayed correctly (if at all) : https://www.slf4j.org/docs.html

[edhu]

ok thanks.

[edhu]

removed the code from the background thread and now i'm seeing what i expected

[edhu]

indeed, it was not in the main thread

[fred.deschenes]

yeah that's what I figured 😉

[fred.deschenes]

and don't worry, no one understands the Java logging frameworks at first (still not sure I really understand either >_>)

[dave08]

Use runBlocking and await or join. CommonPool is the default thread pool dispatcher in coroutines... you need to wait for the result to come back from the thread...

[edhu]

@dave08 thanks. did that and it also works