How do I set the formatter of logger handlers?

In this example we’ll see how to set the formatter for the logger handlers.
We set the formatter by calling the Handler.setFormatter() method.
In the code below we set a SimpleFormatter for our FileHandler
handler and XMLFormatter for the ConsoleHandler
handler.

This SimpleFormatter format the log in a plain text information
while on the other side the XMLFormatter format the log record in
XML format.

package org.kodejava.example.util.logging;

import java.util.logging.*;
import java.io.IOException;

public class LogFormatter {
    public static void main(String[] args) {
        Logger logger = Logger.getLogger(LogFormatter.class.getName());

        try {
            //
            // Create a FileHanlder that will log to mylog.txt with a
            // SimpleFormatter.
            //
            FileHandler simpleHandler = new FileHandler("mylog.txt", true);
            simpleHandler.setFormatter(new SimpleFormatter());
            logger.addHandler(simpleHandler);

            //
            // Create a ConsoleHanlder that will log to the console with
            // an XMLFormatter.
            //
            ConsoleHandler consoleHandler = new ConsoleHandler();
            consoleHandler.setFormatter(new XMLFormatter());
            logger.addHandler(consoleHandler);

            //
            // Do not sent the message to parent handlers. 
            //
            logger.setUseParentHandlers(false);
        } catch (IOException e) {
            logger.log(Level.SEVERE, "Fail to create logger file handler.", e);
        }

        logger.info("Logging application information message.");
        logger.warning("Logging application warning message.");
    }
}

Wayan Saryada

Programmer, runner, recreational diver, live in the island of Bali, Indonesia. Mostly programming in Java, creating web based application with Spring Framework, Hibernate / JPA.

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