I have noticed the appearance of some log4j warnings when I was running a simple spring application.
These messages are like this :
log4j:WARN No appenders could be found for logger (org.springframework.test.context.junit4.SpringJUnit4ClassRunner).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
To fix that just enter the following log4j.resources file into main/resources folder of your project :
# Set root logger level to DEBUG and its only appender to A1.
# A1 is set to be a ConsoleAppender.
# A1 uses PatternLayout.
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
Of course this is a fix that can be applied to the next IntelliJ IDE version, so that the user is not faced with these annoying errors.
Update : If you want to just supress the error messsages use the following line in your starting class