Set Formatter for Logger handler (original) (raw)

With this example we are going to demonstrate how to set a Formatter for a Logger Handler. The Formatter is used by the Handler to format LogRecords. In short, to set a Formatter for a Logger’s handler you should:

• Create a new Logger instance with getLogger(String name) API method of Logger.
• Create a new FileHandler to write to a specific file.
• Add the handler to the Logger, with addHandler(Handler handler) API method of Logger.
• Set a Formatter to the Handler, with setFormatter(Formatter newFormatter) API method. In the example we use the SimpleFormatter and the XMLFormatter.

Let’s take a look at the code snippet that follows:

package com.javacodegeeks.snippets.core;

import java.util.logging.FileHandler; import java.util.logging.Logger; import java.util.logging.SimpleFormatter; import java.util.logging.XMLFormatter;

public class SetFormatterForLoggerHandler {

public static void main(String[] args) throws Exception {
    
    boolean append = false;
    FileHandler handler = new FileHandler("default.log", append);

    Logger logger = Logger.getLogger("com.javacodegeeks.snippets.core");
    logger.addHandler(handler);

    handler.setFormatter(new SimpleFormatter());
    logger.info("simple formatter - info message");

    handler.setFormatter(new XMLFormatter());
    logger.info("xml formatter - info message");
    
}

}

Output:

Nov 19, 2011 4:03:15 PM com.javacodegeeks.snippets.core.SetFormatterForLoggerHandler main INFO: simple formatter - info message Nov 19, 2011 4:03:15 PM com.javacodegeeks.snippets.core.SetFormatterForLoggerHandler main INFO: xml formatter - info message

default.log

Nov 19, 2011 4:03:15 PM com.javacodegeeks.snippets.core.SetFormatterForLoggerHandler main INFO: simple formatter - info message 2011-11-19T16:03:15 1321711395420 1 com.javacodegeeks.snippets.core INFO com.javacodegeeks.snippets.core.SetFormatterForLoggerHandler main 10 xml formatter - info message

This was an example of how to set a Formatter for a Logger Handler in Java.

Ilias is a software developer turned online entrepreneur. He is co-founder and Executive Editor at Java Code Geeks.

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