Logging in Struts – Java Log4j Example
Download Log4j: http://logging.apache.org/log4j/index.html
Log4j Appender:
Create a Log4j properties file (log4j.properties) and define the appender details (where to log and log file details). And put the log4j.properties into your project classpath.
log4j.properties
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# Direct log messages to a log file log4j.appender.file=org.apache.log4j.RollingFileAppender log4j.appender.file.File=C:\\loging.log log4j.appender.file.MaxFileSize=1MB log4j.appender.file.MaxBackupIndex=1 log4j.appender.file.layout=org.apache.log4j.PatternLayout log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n # Direct log messages to stdout log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target=System.out log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n # Root logger option log4j.rootLogger=error, file, stdout |
Struts Action Class:
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//... public class UserAction extends Action{ private static final Logger logger = Logger.getLogger(UserAction.class); public ActionForward execute(ActionMapping mapping,ActionForm form, HttpServletRequest request,HttpServletResponse response) throws Exception { if(logger.isDebugEnabled()){ logger.debug("Starting started"); } //... |
Struts Custom Exception Handler:
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//... public class MyCustomExceptionHandler extends ExceptionHandler{ private static final Logger logger = Logger.getLogger(MyCustomExceptionHandler.class); @Override public ActionForward execute(Exception ex, ExceptionConfig ae, ActionMapping mapping, ActionForm formInstance, HttpServletRequest request, HttpServletResponse response) throws ServletException { //log the error message logger.error(ex); return super.execute(ex, ae, mapping, formInstance, request, response); } } |
Log4j Output File Sample- c:\\logging.log
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12:45:52,210 ERROR MyCustomExceptionHandler:25 - java.io.IOException 12:48:27,672 ERROR MyCustomExceptionHandler:25 - ExceptionConfig[type= java.io.IOException,handler= com.javac.common.exception.MyCustomExceptionHandler, key=error.global.mesage,path=/pages/error.jsp,scope=request] 12:48:54,102 INFO PropertyMessageResources:209 - Operating in Default mode [null] 12:48:54,134 DEBUG sax:1410 - startElement(,web-app,web-app) 12:48:54,134 DEBUG Digester:1417 - Pushing body text '' 12:48:54,134 DEBUG Digester:1436 - New match='web-app' 12:48:54,134 DEBUG Digester:1464 - No rules found matching 'web-app'. |