Question

I set logging level to CONFIG, but don’t see messages written on CONFIG level. What I am missing?

Configuration:

Logger logger = java.util.logging.Logger.getLogger("xxx");
logger.setLevel(java.util.logging.Level.CONFIG);

Tests:

logger.log(java.util.logging.Level.SEVERE, "severe");
logger.log(java.util.logging.Level.WARNING, "warning");
logger.log(java.util.logging.Level.INFO, "info");
logger.log(java.util.logging.Level.CONFIG, "config");
logger.log(java.util.logging.Level.FINE, "fine");
logger.log(java.util.logging.Level.FINER, "finer");
logger.log(java.util.logging.Level.FINEST, "finest");

Output:

SEVERE: severe
WARNING: warning
INFO: info

Answer 1

I typically use logback to implement logging, which seems a tad better documented. So I would recommend switching to that.

But to answer your question, I think what is happening is that your Logger is configured correctly, but the Handler it’s sending its messages to isn’t. The default configuration probably attaches a handler with INFO level logging to the root logger.

edit: I wrote a little test program to verify, you indeed need to set the level on the handler attached to the root logger. You can do so like this:

for (Handler handler : Logger.getLogger("").getHandlers()) {
    handler.setLevel(Level.CONFIG);
}
logger.config("config");

Gives as output:

Feb 11, 2011 4:32:14 PM Test main
CONFIG: config

This sets the level for all handlers attached to this. Obviously a better choice would be writing your own options file and explicitly configuring your loggers. A quick google turned up this article on the subject.

You could also try configuring with a properties file on your classpath that reads:

java.util.logging.ConsoleHandler.level=CONFIG