如何使用org.apache.commons.logging登录到文件？

Question

This may be obvious, but I have been looking for a simple example of using org.apache.commons.logging to log to a specific file (ie /path/to/my-log.txt )

public class MyClass {

    static Log log = LogFactory.getLog(MyClass.class);

    public static void main(String[] args) {

        // What to do here to get log to output to a file???

        log.info("I want to appear in a specific log file")
    }

}

Answer 1

It depends on logging implementation that you have in your project. If you do not have log4j on the classpath, commons-logging default to java.util.logging. In this case you need to configure java.util.logging.FileHander. You can do it thru logging.properties file or programmatically

    Logger.getGlobal().addHandler(new FileHandler("log"));
    LogFactory.getLog(MyClass.class).info("/path/to/mylog.log");

Answer 2

Commons-Logging is just a logging facade, you should use Log4j or JDK-Logging do the real logging tasks, which you can set the log file.

http://logging.apache.org/log4j/1.2/ or http://logging.apache.org/log4j/2.x/

it's configuration file will like:

log4j.rootLogger=info, stdout, R
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p %d{yy-MM-dd HH:mm:ss} %c:%L - %m%n
log4j.appender.R.File=/path/to/mylog.log