I'm a newbie to log4j. This is what I have . I have about 20 files in different packages in a STAND ALONE JAVA APPLICATION.
I am trying to use and write log files.
Following is my log4j.properties file which is in my class path:
log4j.appender.R = org.apache.log4j.DailyRollingFileAppender
log4j.appender.R.File = /ParentFolder/ChildFolder/application.log
log4j.appender.R.Append = true
log4j.appender.R.DatePattern = '.'yyy-MM-dd
log4j.appender.R.layout = org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern = %d{yyyy-MM-dd HH:mm:ss} %c{1} [%p] %m%n
Following is the code to initialize logging in my main method
final String LOG_FILE = "C:/eclipse_workspace/lib/log4j.properties";
Properties logProp = new Properties();
try
{
logProp.load(new FileInputStream (LOG_FILE));
PropertyConfigurator.configure(logProperties);
logger.info("Logging enabled");
}
catch(IOException e)
{
System.out.println("Logging not enabled");
}
In every java class of the application I have the following code
import org.apache.log4j.*;
private static final Logger logger = Logger.getLogger(TheActualClassName.class);
But I get the following warning messages when I run the app.
log4j:WARN No appenders could be found for logger (com.xxx.myApp.MainProgram.MyFileName).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
What am I doing wrong?? The log file "application.log" is not being generated
May need the following line:
# Set root logger level to INFO and appender to R.
log4j.rootLogger=INFO, R
The root logger is always available and does not have a name.
Since the version 1.2.7, log4j (with the LogManager class) looks for log4j.xml in the classpath first. If the log4j.xml not exists, then log4j (with the LogManager class) looks for log4j.properties in the classpath.
Default Initialization Procedure
LogManager xref
If you are going to use a file named log4j.properties, and it's on your application's classpath, there is no need to even call PropertyConfiguration or DOMConfigurator - log4j will do this automatically when it is first initialized (when you first load a logger).
The error message seems to indicate that your configuration is not being loaded.
Add the VM argument -Dlog4j.debug to your application to have log4j spit out a whole bunch of information when it starts up, which includes which files it tries to load and what values it finds in the configuration.
Raghu ,if you are using stand alone configuration for configuring log4j Properties then use can use BasicConfigurator.configure() method for solving your appenders issue.
Related
I'm using the pcap4j library in my application and when I run it I get:
log4j:WARN No appenders could be found for logger (org.pcap4j.core.NativeMappings).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
I also use log4j in my application:
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.11.1</version>
</dependency>
which is configured in main/resources/log4j2-test.properties:
log4j.rootLogger=INFO, fileLogger
log4j.appender.fileLogger.layout=org.apache.log4j.PatternLayout
log4j.appender.fileLogger.layout.ConversionPattern=%d [%t] %-5p (%F:%L) - %m%n
log4j.appender.fileLogger.File=application.log
log4j.appender.fileLogger=org.apache.log4j.DailyRollingFileAppender
log4j.appender.fileLogger.datePattern='.'yyyy-MM-dd-HH-mm
So the configuration file is there and whatever I change in it it has an effect which means log4j sees it and it works, so I'm quite helpless when I read everywhere that this kind of warning is caused by a missing or wrong config file.
Can it be that the error is in the dependency and I can't do anything about it? If so, is there a way to disable the logging in this dependency completely? Actually this is that I would want in the first place anyway.
That message is from log4j 1, whereas you are using log4j2, therefore it is harmless.
https://github.com/apache/log4j/blob/trunk/src/main/java/org/apache/log4j/Hierarchy.java
public
void emitNoAppenderWarning(Category cat) {
// No appenders in hierarchy, warn user only once.
if(!this.emittedNoAppenderWarning) {
LogLog.warn("No appenders could be found for logger (" +
cat.getName() + ").");
LogLog.warn("Please initialize the log4j system properly.");
LogLog.warn("See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.");
this.emittedNoAppenderWarning = true;
}
}
Off topic, sorry :)
You can manually set the log config file using this :
org.apache.log4j.xml.DOMConfigurator.configure("<path>\log4j2-test.properties");
The <path> can either be absolute or relative to the root of your maven module.
I got error:
log4j:WARN No appenders could be found for logger (java.lang.Class).
log4j:WARN Please initialize the log4j system properly.
I have been through many threads and forums to fix the above error, but could not find the solution to my problem.
Problem: My requirement specifies us to use the below filenames for each environment.
log.dev
log.local
log.test
How to configure my application to detect these log files?
log4j must be properly configured for logging to files.
try this :
Logger logger = Logger.getLogger(yourclassname.class);
BasicConfigurator.configure(); // basic log4j configuration
Logger.getRootLogger().setLevel(Level.INFO);
FileAppender fileAppender = null;
try {
fileAppender =
new RollingFileAppender(new PatternLayout("%d{dd-MM-yyyy HH:mm:ss} %C %L %-5p:%m%n"),"file.log");
logger.addAppender(fileAppender);
} catch (IOException e) {
e.printStackTrace();
}
logger.info("TEST LOG ENTRY");
This should create a log file named file.log in the local folder.
Use your java program and logic to removeAppender and addAppender as necessary to switch files.
Or you can create multiple logger instances each with one fileAppender if switching is required dynamically throughout the program.
This way of using log4j avoids the need for external configuration file log4j.properties.
I am building Java Desktop and Java Applet from the same code. Log4j is in use so almost every class in desktop version (which is original) has line like
private static final Logger LOG = LoggerFactory.getLogger(EachClassName.class);
Because Applet is not supposed to perform any io operations I had to exclude this configuration code:
InputStream is = Log4jConfigurator.class.getClassLoader().getResourceAsStream(path);
properties.load(is);
is.close();
PropertyConfigurator.configure(properties);
But now I get warnings because getLogger is still in place
log4j:WARN No appenders could be found for logger (org.game.client.Client).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
What would be the most elegant solution to avoid this warnings and use logger only in desktop version?
In your "Applet App" try to configure log4j programmatically:
turn off logging
LogManager.getRootLogger().setLevel(Level.OFF);
Add NullAppender (if setting Level.OFF is not enough)
LogManager.getRootLogger().addAppender(new NullAppender())
am using log4j-1.2.15.jar for enable logging .and its writing all logs to a file.
this is what in my log4j.properties.
log4j.rootLogger = DEBUG, fileout
log4j.appender.fileout = log.NewLogForEachRunFileAppender
log4j.appender.fileout.layout.ConversionPattern = %d{ABSOLUTE} %5p %c - %m%n
log4j.appender.fileout.layout = org.apache.log4j.PatternLayout
log4j.appender.fileout.File = D:/log/logs.log
It was working fine when am trying to run this from my local server configured in eclipse.
But the same is not working when i had deployed that into the production development enviornment.This is what am getting in the console.
no output stream or file set for the appender named [fileout]
Can anyone give a solution.?
Your configuration looks ok. I assume the D:/log/logs.log is available in production environment.
You might want to try log4j configuration debugging by setting -Dlog4j.debug on the command line. It often points out useful configuration errors.
I have a log4j properties file which is creating a file inside my tomcat>bin folder but instead can it write the log file to my project's root dir? webapps>test>___?
Here is my log4j properties file contents.
#define the console appender
log4j.appender.consoleAppender = org.apache.log4j.ConsoleAppender
# now define the layout for the appender
log4j.appender.consoleAppender.layout = org.apache.log4j.PatternLayout
log4j.appender.consoleAppender.layout.ConversionPattern=%t %-5p %c{3} - %m%n
log4j.appender.rollingFile=org.apache.log4j.RollingFileAppender
log4j.appender.rollingFile.File=/test/a.log
log4j.appender.rollingFile.MaxFileSize=10MB
log4j.appender.rollingFile.MaxBackupIndex=2
log4j.appender.rollingFile.layout = org.apache.log4j.PatternLayout
log4j.appender.rollingFile.layout.ConversionPattern=%p %t %c - %m%n
# now map our console appender as a root logger, means all log messages will go to this appender
#for console printing
#log4j.rootLogger = DEBUG, consoleAppender
#for file printing
log4j.rootLogger = DEBUG, rollingFile
Try replacing this:
log4j.appender.rollingFile.File=/test/a.log
with this:
log4j.appender.rollingFile.File=../webapps/test/a.log
Note (by Stephen C) - the "../" means this solution depends on whether or not the Tomcat launch mechanism you use makes $CATALINA_HOME the current directory before the JVM that hosts Tomcat. Some do, and some don't.
The log4j configurations understand "${catalina.home}", so ...
log4j.appender.rollingFile.File=${catalina.home}/webapps/test/a.log
However, I don't think it is a good idea to put logs into the webapps tree because they are liable to be blown away if your webapp is redeployed.
Put them in ${catalina.home}/logs instead.
Or better still, put them in the distro-specific conventional place to put application logfiles; e.g. "/var/spool/..." or "/var/log/...".
Putting logfiles in standard places means there are less places for someone else (e.g. the guy who is the backup sysadmin when you are on holiday) to investigate if the file system fills up with old logfiles.