Can't configure logging for executable jar

Question

This is similar to this other question, although I already put the logging.properties in the executable jar and doesn't work.

I have a class (ReportGenerator) that has the following:

 Logger logger = Logger.getLogger(ReportGenerator.class.getName());
 logger.log(Level.INFO, "LOG THIS");  

I'm using Netbeans so I put the logging.properties file in the path src/main/resources. It has this (among other things):

# default file output is in user's home directory.
java.util.logging.FileHandler.pattern = /my/folder/reports.log
java.util.logging.FileHandler.limit = 50000
java.util.logging.FileHandler.count = 10
java.util.logging.FileHandler.formatter = java.util.logging.SimpleFormatter

# Limit the message that are printed on the console to INFO and above.
java.util.logging.ConsoleHandler.level = OFF
java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter


############################################################
# Facility specific properties.
# Provides extra control for each logger.
############################################################

# For example, set the com.xyz.foo logger to only log SEVERE
# messages:
com.mypackage.ReportGenerator.level = ALL

The jar is generated using Maven, when decompressed I can see that the logging.properties is in the main folder of the jar. Along with the folder com where my class is.

-com
  -mypackage
      -ReportGenerator
logging.properties
...other things

When I run from console:

java - jar MyReportsJar.jar

It shows me the logs through the console. I want to log it to the file I set in the logging.properties.

What am I doing wrong? How do I do it without setting the JVM java.util.logging.config.file param?

Answer 1

After dealing a few days against this and reading many resources on the Internet I came up with this solution:

I have to change the logging properties of the LogManager in the program. I can use the logging.properties file packaged in the .jar like this:

LogManager.getLogManager().readConfiguration(ReportGenerator.class.getClassLoader().getResourceAsStream("logging.properties"));

And then I can do the same as before to get the logger and log:

 Logger logger = Logger.getLogger(ReportGenerator.class.getName());
 logger.log(Level.INFO, "LOG THIS"); 

But I found very useful that you can specify another logging.properties file on runtime so my final code is this:

        String logFile = System.getProperty("java.util.logging.config.file");
        if(logFile == null){
            LogManager.getLogManager().readConfiguration(ReportGenerator.class.getClassLoader().getResourceAsStream("logging.properties"));
        }                
        Logger logger = Logger.getLogger(ReportGenerator.class.getName());
        logger.log(Level.INFO, "LOG THIS"); 

That way, if I execute the jar as this:

java -jar MyReportsJar.jar

It uses the internal logging.properties file.

But if I execute:

java -Djava.util.logging.config.file=<external-logging.properties> -jar MyReportsJar.jar

it uses the external logging.properties file.