Hi,
It is ok I have found how to change a bundle of the openhab-core.
It is explain in this post:
At the distribution of the extracted zip file (explained in step 2 of the post HowTo: Setup IntelliJ for binding development). I just need to clear the cache and change the jar files in the runtime directory (in my case in runtime/system/org/openhab/core/bundles/org.openhab.core and in /runtime/system/org/openhab/core/bundles/org.openhab.core.io.console).
Thank you,
Nicolas Gennart.