log4j.properties File not found

I know this questin was already asked but I can't find/understand my error message. Here't the thing. I want to use log4j on an Apache Tomcat 8.5 with eclipse for a web application. So log4j works and I created a log4j.properties file. I placed it in my /src like it is adviced. Now comes the confusing thing for me. I get an Error Message:

log4j:ERROR Could not read configuration file [log4j.properties]. java.io.FileNotFoundException: log4j.properties (Das System kann die angegebene Datei nicht finden)

After this error, I get de log I am expecting. So is there maybe a place the compiler searches the file before it searches in the src folder or do I have to add any other depency. In addition, I'm not using Maven. THX