Question

I’m running a web app under tomcat and I’ve configured logging like this (via a contextInitialized hook):

    Logger rootLogger = Logger.getLogger("");
    String date = new SimpleDateFormat("yyyy-MM-dd").format(new Date());
    FileHandler logHandler = new FileHandler(
        "myapp_" + date + "_%u.log",
        524288000, // 500 MB max size
        1, // one log file at a time
        true // if it exists: append, don't overwrite
    );
    Level defaultLevel = Level.INFO;
    logHandler.setFormatter(new XMLFormatter());
    logHandler.setLevel(defaultLevel);
    for (Handler h : rootLogger.getHandlers()) {
        rootLogger.removeHandler(h);
    }
    rootLogger.setLevel(defaultLevel);
    rootLogger.addHandler(logHandler);

Unfortunately the logs don’t get created under /var/log. They get created in /var/lib/tomcat6/ like /var/lib/tomcat6/myapp_2012-08-13_0.log. I’d like to change it to /var/log/myapp/ like: /var/log/myapp/myapp_2012-08-13_0.log I don’t see anything I can set on the FileLogger to make this happen. Am I missing something obvious, or is there a way to achieve it?

Answer 1

You could use a JVM property to prepend to the file name. In the below sample pass in something like -Dlog_directory=C:\logs

package sample;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.logging.FileHandler;
import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.logging.XMLFormatter;

import org.apache.commons.lang.StringUtils;

public class stackoverflow11937181 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        Logger rootLogger = Logger.getLogger("");
        String date = new SimpleDateFormat("yyyy-MM-dd").format(new Date());
        String logDirectory = System.getProperty("log_directory");
        String logFile = (logDirectory == null ? StringUtils.EMPTY : logDirectory) + "/myapp_" + date + "_%u.log";
        try {
            FileHandler logHandler = new FileHandler(logFile, 524288000, // 500 MB max size
                    1, // one log file at a time
                    true // if it exists: append, don't overwrite
            );
            Level defaultLevel = Level.INFO;
            logHandler.setFormatter(new XMLFormatter());
            logHandler.setLevel(java.util.logging.Level.FINE);
            for (Handler h : rootLogger.getHandlers()) {
                rootLogger.removeHandler(h);
            }
            rootLogger.setLevel(defaultLevel);
            rootLogger.addHandler(logHandler);

        }
        catch (SecurityException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        rootLogger.log(Level.FINE, "sample");

    }

}