Log4j Jump Start PRO

Log4j is an open source project developed and maintained by Apache. It is part of a bigger open source project known as the Apache Logging Services.

The following code sample shows how to use Log4j in its basic configuration.

package il.ac.hit.samples;

import org.apache.log4j.BasicConfigurator;
import org.apache.log4j.Logger;

public class SimpleLoop
{
	static Logger logger = Logger.getLogger("SimpleLoop");

	public static void main(String args[])
	{
		BasicConfigurator.configure();
		for (int i = 0; i <= 10; i++)
		{
			System.out.println("i=" + i);
			logger.info("i equals " + i);
		}
	}

}

The following video clips shows the execution of this code sample and explains it.

The following code sample shows how we can add a FileAppender to the logger we use.

package il.ac.hit.samples;

import java.io.IOException;

import org.apache.log4j.BasicConfigurator;
import org.apache.log4j.FileAppender;
import org.apache.log4j.Logger;
import org.apache.log4j.SimpleLayout;

public class SimpleLoopFileAppender
{
	static Logger logger = Logger.getLogger("SimpleLoop");

	public static void main(String args[])
	{
		BasicConfigurator.configure();
		try
		{
			logger.addAppender(new FileAppender(new SimpleLayout(), "logs.txt"));
		}
		catch (IOException e)
		{
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		for (int i = 0; i <= 10; i++)
		{
			System.out.println("i=" + i);
			logger.info("i equals " + i);
		}
	}

}

The following video clip shows and explains the execution of this code.