I am using log4j for my logs. My application has a simple XML configuration file and I need to have in my config file the path for the log file. At the moment, it's another XML configuration file for log4j that contains this:
<log4j:configuration>
<appender name="file" class="org.apache.log4j.FileAppender">
<errorHandler class="org.apache.log4j.helpers.OnlyOnceErrorHandler" />
<param name="file" value="log.out" />
(..........)
(log.out is the default log which is in the project's directory.) How can I move this configuration into my application's configuration file?
There are basically three options:
During the build, create a config for log4j which contains an absolute path for the file parameter. Least flexible.
Use a System property. While this gives you some flexibility, this causes problems when you run in a container (J2EE server) and you have several applications which all use log4j.
The second option comes in two flavors:
You can specify the path for the log file using ${logFile} in the XML and use -DlogFile= on the command line to specify the path.
You can keep the XML config in a different place and tell log4j to load it when it starts using -Dlog4j.configuration=/absolute/path/to/log4j.xml
Related articles:
http://www.jroller.com/rmcmahon/entry/system_properties_in_log4j_properties
Log4J change File path dynamically
Log4j: How to configure simplest possible file logging?
http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/FileAppender.html
Related
A Java application makes use of the Apache logging but am unable to turn it on.
The application is a Java Web Start application which uses a signed Jar file so I am unable to make any changes to the Jar file or the code.
A log4j.properties file with the following content was created and place in all the Java_Home/bin directories on my machine to ensure it will be picked up.
log4j.appender.rollingFile=org.apache.log4j.RollingFileAppender
log4j.appender.rollingFile.File=c:/MyLoggingDir/application6.log
log4j.appender.rollingFile.layout=org.apache.log4j.PatternLayout
log4j.appender.rollingFile.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %m%n
log4j.appender.rollingFile.MaxFileSize=10MB
log4j.appender.rollingFile.MaxBackupIndex=5
log4j.appender.rollingFile.append=true
log4j.rootCategory=ALL, rollingFile
When the application starts no output is visible in the Java Console and no files are created in the c:/MyLoggingDir directory.
Is there another requirement missing that needs to be set in order to obtain output?
From the documentation of log4j:
Log4j will inspect the "log4j.configurationFile" system property and,
if set, will attempt to load the configuration using the
ConfigurationFactory that matches the file extension.
So, for example, if you put the property file in C:\Configuration\log4j.properties, you should run your application with the flag -Dlog4j.configuration="file:C:\Configuration\log4j.properties"
See also this other answer.
I have an ear deployed in weblogic with the log4j2.xml logPath set as
<Property name="logPath">some_path_1<Property>
and a logger defined as
<Logger name="a.b.c.d" level="INFO" />
Inside this ear/lib there is a jar containing a log4j2.xml and the logPath property is defined as
<Property name="logPath">some_path_2<Property>
and a logger with a very similar packaging structure
<Logger name="a.b.c" level="INFO" />
Both log4j2.xml's are configured to have a different log file name as well.
But the logs for both are coming in the path some_path_2 and with the file name defined in that jar
How to ensure both logging outputs happens separately as defined?
My ear structure is like
ear
|--lib
|--|--abc.jar
|--|--|--log4j2.xml //the one thats getting loaded
|--xyz.war
|--|--WEB-INF
|--|--|--classes
|--|--|--|--log4j2.xml // the one I want
Edit1: I added the following in the containing war's web.xml but it did not help
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>/WEB-INF/classes/log4j2.xml</param-value>
</context-param>
Edit2: I also tried this and found that this is working intermittently
ear
|--lib
|--|--abc.jar
|--|--|--log4j2.xml //the one thats getting loaded
|--|--xyz.jar
|--|--|--log4j2.xml //the one I want.. works but not always.Does classloader loads the jars alphabetically?
|--xyz.war
|--|--WEB-INF
|--|--|--classes
|--|--|--|--log4j2.xml // the one I want
Log4j is initialized only once by using the configuration file which is first found by the log4j bootstrapper. All other (possible present) configuration files will not be taken into account. Learn more on the precedences of log4j auto configuration in the appropriate tutorials.
As you probally already know your problem is that only one configuration-file gets loaded and which one depends on the classloader. So you should not rely on that.
There are only two possible soulutions for your problem, but today I do not have the time to work it out for you - sorry. You have to remove or rename the config-file in abc.jar
Remove log4j2.xml from abc.jar
Do it with your build-script in ANT/MAVEN/GRADLE or whatever. Copy-paste the interessting parts of the config-file in your config-file.
Rename log4j2.xml inside abc.jar
Do it with your build-script in ANT/MAVEN/GRADLE or whatever. Now you could include the whole config-file in your log4j2.xml. This is called CompositeConfiguration.
I hope this little advice will help you.
Good luck!
Can you remove the XMLs from the jar/war and use only one xml file at the ear level which has details of both the logging paths/properties. You can try to reconfigure log4j2 in code with a specific configuration file.
You can also dynamically write to separate log files, but I personally haven't tried this so I wouldn't be able to guide more on this.
Are you sure you want to use "log4.xml" file to be use by log4j2. I don't think, log4j2 automatic configuration mechanism try to find out configuration file with name "logj.xml".
From official documentation,
Log4j has the ability to automatically configure itself during
initialization. When Log4j starts it will locate all the
ConfigurationFactory plugins and arrange them in weighted order from
highest to lowest. As delivered, Log4j contains four
ConfigurationFactory implementations: one for JSON, one for YAML, one
for properties, and one for XML.
Log4j will inspect the "log4j.configurationFile" system property and,
if set, will attempt to load the configuration using the
ConfigurationFactory that matches the file extension.
If no system property is set the properties ConfigurationFactory will look for log4j2.properties or log4j2.json or log4j2.xml files in classpath.
Possibly you should try to rename the file "xyz.war//WEB-INF/classes/log4j.xml" to "xyz.war//WEB-INF/classes/log4j2.xml". Obviously content of this file must confirm to log4j configuration xsd.
I use log4j in my spring mvc project and I create log file uing log4j.properties in the following.
# Root logger option
log4j.rootLogger= INFO, info, file, stdout, error
# Direct log messages to a log file [INFO]
log4j.appender.info=org.apache.log4j.DailyRollingFileAppender
log4j.appender.info.File=.logs\\mylog.log
log4j.appender.info.Threshold=INFO
log4j.appender.info.MaxFileSize=1Kb
log4j.appender.info.MaxBackupIndex=10
log4j.appender.info.DatePattern='.'yyyy-MM-dd
log4j.appender.info.layout=org.apache.log4j.PatternLayout
log4j.appender.info.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
I want it to be stored in myapp/logs folder in my web application . what part i should for the file.
here is the directory
Right now it will be saved in the current working directory of your IDE (Eclipse or STS, I guess). Its not a good idea to put the file in the project structure, because that structure wont exist, once you deployed the app anywhere.
In Spring you can define a property in youe web.xml, to make the location variable:
<context-param>
<param-name>webAppRootKey</param-name>
<param-value>mywebapp.root</param-value>
</context-param>
Then add a variable to your config:
log4j.appender.info.File=${mywebapp.root}/logs/mylog.log
If you have to store it in the application, you can also define that programmatically, by makeing use of "ServletContext.getRealPath(".") to find out where your app is deployed, and then set the path to the file.
In the normal scenario web-app checks for your log file at the root of your class path. To load a file from custom location , have a look at below posts
Change location of log4j.properties
How to use custom file instead of log4j.properties
EDIT :
From op's comment to generate your log file in the projects path , where you have placed your logs directory . you can simply specify it as ,
log4j.appender.file.File= logs/mylog.log
I was wondering if there is a way to define the appenders (file, console etc) on a different file than the one defining the actual logging properties.
The idea came up from a system I am developing and we have the following requirement:
Different versions of the system will be deployed on the same server. So in order not to maintain different log4j properties file, that will all set the same properties and differ on the file appenders (so as to know which log was recorded from which version of the system).
Thank you in advance
You can use DOMConfigurator or PropertyConfigurator to load your log4j settings from an external file. You can invoke this API multiple times under a run to load the settings from different sources.
In your case, you can load the Appender details alone dynamically from another property file based on the version.Just like suffixing some version id to the file name and loading it from your code in a generic way.
If each version running on a different VM process (on different ports), you can add an argument to the virtual machine. e.g.:
-Dmysystem.version=1.0.1
If you are using the XML configuration:
<param name="file" value="/logs/system.v${mysystem.version}.log" />
Of if you are using the properties:
log4j.appender.ROLL.File=/logs/system.v${mysystem.version}.log
In both cases, the generated file might be:
/logs/system.v1.0.1.log
In this way, you can maintain a single configuration file and dynamic filenames.
i would like to turn of my debug statements at runtime in log4j2. According to the documentation we can do this. I kept my log4j.xml file in default package and then made jar out of it. Since I cannot modify jar i specified xml file using Dlog4j.configuration=/path/to/log4j.xml. However,this is not working. I Tried everything using file:// uri to all the combination, still it is not picking the xml.
The system property to specify the config file location is different from log4j-1.x.
In log4j2, the property is "log4j.configurationFile".
So if the config is in a jar file you would use:
-Dlog4j.configurationFile=jar:file:///C:/path/to/jarfile.jar!/path/to/log4j2.xml
(I assume you have the monitorInterval set in your configuration as documented here: http://logging.apache.org/log4j/2.x/manual/configuration.html#AutomaticReconfiguration)
Following must be added to configuration file:
<Configuration monitorInterval="60" >