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log4j configuration file and jar application

I'm using the log4j2 library to manage the logging process.
I created a configuration file named log4j2.xml containing the Appenders and Loggers configurations. Then, I defined a Logger in each class
private static Logger my_logger = LogManager.getLogger(my_class);
I did not specify anywhere the name of the conf file, so I think that the library implicitly get and read it.
Now, I need to provide my application in the form of a jar file, so I need to make the config file available so that the user can modify and configure it.
In my case, I suggest to create a XXX folder at the level of the jar file, containing all the configuration files used by my app.
My question is how can I say to the app "get XXX/log4j2.xml" rather than the xml contained into the jar.

that config file must be located in the class path, if you want the app to read the configuration from any other location then you need to specify that using
PropertyConfigurator.configure("/myPath/log4j.properties");

Make any folder and put your property or xml file in that. In order to read the property file you can do something like this:
Properties objProperties = new Properties();
<your-class>.class.getClassLoader().getResource("folder/log4j.properties");
objProperties.load(isFile);
or, Also this:
InputStream ist = Thread.currentThread().getContextClassLoader().getResourceAsStream("folder/log4j.properties");
In case of java web application please use the link

I had a similar task a few weeks ago.
I solved it this way:
Store a template of your log4j2.xml inside your jar files resource folder
When running your application, check for a file named log4j2.xml in the jar files current directory
If there is one, use that to create your logger
If not, copy your template from within your jar to the jar files directory and then use that to create your logger.
Cheers

how to change configuration file of log4j2 at runtime?

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" >

netbeans and hibernate configuration

How can I load the configuration information for hibernate dynamically from a config file. Netbeans currently hard codes that information into an xml file that is then compiled into the jar. I'm a newbie to Java/Netbeans coming from PHP land and am use to a central bootstrap that pulls from a .ini or something similar, but netbeans tends to hardcode this information upon generation of the models,etc in an xml file that is then compiled in the jar. I'm looking for conventional methods of setting up configuration for various client machines using various database configurations. I don't want to have to compile the app on each machine it must be installed on.

The configuration file is read using the Configuration class. By default, it uses the hibernate.cfg.xml file found in the classpath, but you can use the configure method taking a file as parameter, and store the config file on the file system rather than in the jar.
You can also put the static mapping, which never changes between configs, in a file inside the jar, and put the varying config inside an external file. Look at the javadoc for Configuration to know how to add resources and config files to the configuration.

Can I use log4j in a web app with a file other than log4j.xml or log4j.properties?

Is it possible to use something other than the file names log4j.xml or log4j.properties to configure log4j logging in a Java web application?
I want to load a log4j.xml file from a different location on the file path (not in my classpath). Is that possible in a web application using say, JBoss or Tomcat?

You can use PropertyConfigurator.Call configure with file you wanted

Use -Dlog4j.configuration=path/to/your/file.xml startup parameter to specify where your configuration file is. It's the recommended practice anyway:
The preferred way to specify the default initialization file is
through the log4j.configuration system property.
(log4j manual)

Loading a configuration file from the classpath

I'm working on making my Java app easy to deploy to other computers and am writing an ant script to do so, that is going fine.
I'm having trouble loading resources that are listed in the classpath named in the manifest file of the jar.
Folder structure looks like this:
/MyProgram.jar
/lib/<dependencies>
/config/configuration.xml
I can not for the life of me access the configuration.xml file using the ClassLoader. It, along with all the dependencies are listed explicitly in the Class-Path entry to the manifest file.
I've tried many variants of the following:
this.xml = Thread.currentThread().getContextClassLoader()
.getResourceAsStream(xmlName);
this.xml = this.getClass().getResourceAsStream(xmlName);
With xmlName as a string of all the following values:
"config/configuration.xml"
"configuration.xml"
"config.configuration.xml"
Related to this, I also have a log4j.properties file in the config directory. How do I get log4j to pick it up? Other references say it just needs to be in the classpath, and it too is explicitly named in the jar's manifest file. Can someone point me in the right direction?
Update:
Here are the actual entries from Class-Path:
Class-Path: <snip dependencies> config/configuration.xml config/log4j.properties

Classpath entries should either be directories or jar files, not individual files. Try changing your classpath to point to the config directory instead of the individual config files.
this.xml = Thread.currentThread().getContextClassLoader()
.getResourceAsStream("config.xml");
Better yet would be to just include your config directory in MyProgram.jar. This would prevent you from needing to add it specifically to the classpath.
this.xml = Thread.currentThread().getContextClassLoader()
.getResourceAsStream("/config/configuration.xml");

As far as I know, log4j.xml should be at root of your classpath..
and also, you can read your configuration file with below code script. and config directory should be at your classpath.
this.xml = this.getClass().getResourceAsStream("/config/configuration.xml");

You can use the log4j.configuration system property when you startup your application:
java -Dlog4j.configuration=config/log4j.properties MyApp
See http://logging.apache.org/log4j/1.2/manual.html under "Default Initialization Procedure".
Regarding the other configuration files not being picked up, what does your Manifest.mf file looks like? Are you using something like
Class-Path: config/configuration.xml lib/yourLibOne.jar lib/blah.jar
in your Manifest.mf file?

Regarding log4j : If you want it to use a different config file from the default, you can use
org.apache.log4j.PropertyConfigurator.configure(...)
Variants of this static method accept URL, Properties or file name.
There is also
org.apache.log4j.xml.DOMConfigurator
for the XML files.