Learn Logging in Java

LearnApacheLogging.java

package learn.java.logger;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class LearnApacheLogging {
    private static final Logger logger = LogManager.getLogger(LearnApacheLogging.class.getName());
    
    public static void main(String[] args){
        logger.fatal("Case 1: Start time : {}", System.currentTimeMillis());
        for (int i = 0; i < 100000; i++) {
            logger.debug("Entry number: {} is ", i);
        }
        logger.fatal("Case 1: End time : {}", System.currentTimeMillis());
        
        logger.fatal("Case 2: Start time : {}", System.currentTimeMillis());
        for (int i = 0; i < 100000; i++) {
            if(logger.isDebugEnabled()){
                logger.debug("Entry number: {} is ", i);
            }
        }
        logger.fatal("Case 2: End time : {}", System.currentTimeMillis());
        
        logger.fatal("Case 3: Start time : {}", System.currentTimeMillis());
        for (int i = 0; i < 100000; i++) {
            logger.debug("Entry number: " + i + " is ");
        }
        logger.fatal("Case 3: End time : {}", System.currentTimeMillis());
        
        
        logger.fatal("Case 4: Start time : {}", System.currentTimeMillis());
        for (int i = 0; i < 100000; i++) {
            logger.debug("Static Log");
        }
        logger.fatal("Case 4: End time : {}", System.currentTimeMillis());
        
        logger.fatal("Case 5: Start time : {}", System.currentTimeMillis());
        for (int i = 0; i < 100000; i++) {
            if(logger.isDebugEnabled()){
                logger.debug("Static Log");
            }
        }
        logger.fatal("Case 5: End time : {}", System.currentTimeMillis());
    }
}