Logging application log to a log file(by File Appender)

To log your application log to a log file by using log4j, you have to go through the following steps:

1. Download latest jar of log4j.jar and add it to your project classpath.
2. Create a log4j.properties file inside your source directory to define properties of your logger.
3. To log your application log to a log file, you need to add the following code in the log4j.properties

 
#################################################################
#####     Application Logs to be printed in the log file    #####
#################################################################
 
log4j.rootLogger= WARN, FILE_APPENDER

# test appender  daily rolling logs format
log4j.appender.FILE_APPENDER=org.apache.log4j.DailyRollingFileAppender
log4j.appender.FILE_APPENDER.File=logs/autoLog.log
log4j.appender.FILE_APPENDER.DatePattern='.'yyyy-MM-dd
log4j.appender.FILE_APPENDER.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE_APPENDER.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %5p (%F:%M:%L) - %m%n

# test appender  daily rolling logs for packages
log4j.logger.com.myorg=DEBUG
log4j.logger.com.myorg.core.util=FILE_APPENDER
log4j.logger.com.myorg.core.page=FILE_APPENDER

4. To know the usage of logger see the below code:

   //In ConfigUtil.java
   private static Logger log = Logger.getLogger(ConfigUtil.class);
   // The below line is called inside static block
   log.info("Properties file loaded at '" + configLoc + "'");
   
   //In BasePage.java
   protected static Logger log = Logger.getLogger(BasePage.class);
   // The below line is called inside setTimeout() method
   log.info("The timeout value is set to " + timeoutSeconds + " seconds.");
   
   //In DriverManager.java
   private static Logger log = Logger.getLogger(DriverManager.class);
   // The below line is called inside static block
   log.info("Driver location is set to '" + driverLoc + "'");
   

5. You will get your application log in the log file(which you have specified in your log4j.properties, in this example i have specified "logs/autoLog.log" file) as shown in the below sample:
   

    
   2013-09-05 12:36:04  INFO (ConfigUtil.java::39) - Properties file loaded at '/Users/aksahu/MySpace/Web_Workspace/KnowledgeBase/config/config.properties'
   2013-09-05 12:36:04  INFO (BasePage.java:setTimeout:155) - The timeout value is set to 60 seconds.
   2013-09-05 12:36:04  INFO (DriverManager.java::54) - Driver location is set to '/Users/aksahu/MySpace/Web_Workspace/CoreDriver/drivers/'
   2013-09-05 12:36:04  INFO (DriverManager.java:getDriver:85) - initializing 'chrome' driver...
   2013-09-05 12:36:15  INFO (BasePage.java:windowMaximize:101) - Maximizing the browser window.
   2013-09-05 12:36:17  INFO (BasePage.java:openUrl:86) - Openning the url 'http://knowledgebase-wiki.appspot.com/' in the browser...
   2013-09-05 12:36:23  INFO (BasePage.java:waitForPageToLoad:956) - Waiting for page to load...
   2013-09-05 12:36:23  INFO (BasePage.java:typeByID:195) - Entering text 'java' to the element specified by id 'searchField'
   2013-09-05 12:36:23  INFO (BasePage.java:clickByID:258) - Clicking on the element specified by id 'resultDiv0'
   2013-09-05 12:36:23  INFO (BasePage.java:waitForElementLocatedByXpath:848) - Waiting for the element specified by xpath '//a[contains(text(),'[Go to page]')]'
   2013-09-05 12:36:23  INFO (BasePage.java:clickByXpath:238) - Clicking on the element specified by xpath '//a[contains(text(),'[Go to page]')]'
   2013-09-05 12:36:24  INFO (BasePage.java:waitForPageToLoad:956) - Waiting for page to load...
   2013-09-05 12:36:24  INFO (BasePage.java:isTextPresent:807) - Checking for the text 'Installing Java' in the page
   2013-09-05 12:36:24  INFO (BasePage.java:isTextPresent:807) - Checking for the text 'java' in the page
   2013-09-05 12:36:24  INFO (BasePage.java:quitBrowser:582) - Closing all the instances of the browser 'chrome'