Creating a Custom Formatter for a Logger Handler : Log Formatter « Log « Java Tutorial

import java.util.Date;
import java.util.logging.FileHandler;
import java.util.logging.Formatter;
import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.Logger;

class MyHtmlFormatter extends Formatter {
  public String format(LogRecord rec) {
    StringBuffer buf = new StringBuffer(1000);
    if (rec.getLevel().intValue() >= Level.WARNING.intValue()) {
      buf.append("<b>");
      buf.append(rec.getLevel());
      buf.append("</b>");
    } else {
      buf.append(rec.getLevel());
    }
    buf.append(' ');
    buf.append(rec.getMillis());
    buf.append(' ');
    buf.append(formatMessage(rec));
    buf.append('\n');
    return buf.toString();
  }

  public String getHead(Handler h) {
    return "<HTML><HEAD>" + (new Date()) + "</HEAD><BODY><PRE>\n";
  }

  public String getTail(Handler h) {
    return "</PRE></BODY></HTML>\n";
  }
}

public class Main {
  public static void main(String[] argv) throws Exception {
    Logger logger = Logger.getLogger("com.mycompany");
    FileHandler fh = new FileHandler("mylog.html");
    fh.setFormatter(new MyHtmlFormatter());
    logger.addHandler(fh);

    logger.setLevel(Level.ALL);
    logger.severe("my severe message");
    logger.info("my info message");
    logger.entering("Main class", "myMethod", new Object[] { "para1", "para2" });
  }
}

35.4.Log Formatter
	35.4.1.	Set log Formatter
	35.4.2.	Create custom formatter
	35.4.3.	Define your own Custom Formatter
	35.4.4.	Log HTML formatter
	35.4.5.	Logger with XMLFormatter and FileHandler
	35.4.6.	XMLFormatter based Logging
	35.4.7.	Creating a Custom Formatter for a Logger Handler
	35.4.8.	Setting the Formatter of a Logger Handler