PropertyConfigurator in Log4j?

PropertyConfigurator:

If we create a properties file (.properties), then we should use Property Configurator class for loading that file.

You need to use the PropertyConfigurator.configure() method to configure log4j using a properties file.Log4j should be configured only once for the entire application.

Note:-  properties file contains only key and value.

Example 1:-

Program for using ConsoleAppender and SimpleLayout from DEBUG level.

log4j.properties

log4j.rootLogger=DEBUG,A1

log4j.appender.A1=org.apache.log4j.ConsoleAppender

log4j.appender.A1.layout=org.apache.log4j.SimpleLayout

Sample.java

package com.dustbin.test;

import org.apache.log4j.Logger;

import org.apache.log4j.PropertyConfigurator;

public class Sample {

static Logger logger=Logger.getLogger(Sample.class);

public static void main(String[] args) {

PropertyConfigurator.configure("c:/logs/log4j.properties");

logger.info("info message");

logger.warn("warn message");

logger.error("error message");

logger.fatal("fatal message");

logger.debug("debug msg");

}

}

Output:

INFO - info message

WARN - warn message

ERROR - error message

FATAL - fatal message

DEBUG - debug msg

Some times we get below type exception ....

log4j:ERROR Could not read configuration file [C:/log/log4j.properties].

java.io.FileNotFoundException: C:\log\log4j.properties (The system cannot find the path specified)

Note:-specify absolute path of the log4j.properties file