Why is sun.net logging at DEBUG level in my Play application?

Question

I have a Play 2.2 application and sun.net.www.protocol.http.HttpURLConnection is logging at debug level. Why is this happening? I don't have any logging.properties file in my project. I have a logback config file, with the root level set to DEBUG, but that should only affect logging through logback... which presumably internal JDK classes do not use.

Answer 1

It is because org.slf4j.jul-to-slf4j-1.7.5.jar is depended on by Play 2.2.0, and that redirects all java-util-logging logging through slf4j, which is configured here to go through logback. So the logback configuration will also affect java-util-logging.