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Log4j2.xml configuration doesn't work but log4j2.properties does

Hello I have this problem were if i use a log4j2.xml file as a configuration file the logger won't log to console, whereas if i am using a .properties file instead i will have the logs in file.
This is the .xml file
<?xml version="1.0" encoding="UTF-8"?>
<!-- Extra logging related to initialization of Log4j.
Set to debug or trace if log4j initialization is failing. -->
<Configuration status="warn">
<Appenders>
<!-- Console appender configuration -->
<Console name="console" target="SYSTEM_OUT">
<PatternLayout
pattern="%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n" />
</Console>
</Appenders>
<Loggers>
<!-- Root logger referring to console appender -->
<Root level="info" additivity="false">
<AppenderRef ref="console" />
</Root>
</Loggers>
</Configuration>
.properties file:
# Set to debug or trace if log4j initialization is failing
status = warn
# Name of the configuration
name = ConsoleLogConfigDemo
# Console appender configuration
appender.console.type = Console
appender.console.name = consoleLogger
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = %d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Root logger level
rootLogger.level = debug
# Root logger referring to console appender
rootLogger.appenderRef.stdout.ref = consoleLogger
(I am trying to do this for a migration from log4j to log4j2 and if i am using the .properties file everything seems to work)

I had the properties file and xml file both in resources folder.

why is my log file empty when I use log4j2?

please help me debug something-- I am getting an empty log file when I use log4j2.
Here is my log4j2.properties file:
# Root logger option
name=PropertiesConfig
property.filename = logs
appenders = stdout, file
# stdout will print logs on console
appender.stdout.name = consoleLogger
appender.stdout.type = Console
appender.stdout.target = System.out
appender.stdout.layout.type = PatternLayout
appender.stdout.layout.pattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# file will print logs in file
appender.file.name = fileLogger
appender.file.type = File
appender.file.fileName=ProtScannerLog.log
appender.file.layout.type = PatternLayout
appender.file.layout.pattern = %d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
loggers=file
logger.file.name = log4j2.properties
logger.file.level = info
logger.file.appenderRefs = file
logger.file.appenderRef.file.ref = fileLogger
rootLogger.level = info
rootLogger.appenderRefs = stdout, file
rootLogger.appenderRef.stdout.ref = consoleLogger
rootLogger.appenderRef.file.ref = fileLogger
# added for debugging
# logs the SQL statements
log4j.logger.org.hibernate.SQL=DEBUG
# Logs the JDBC parameters passed to a query
log4j.logger.org.hibernate.type=TRACE
log4j.appender.hb=org.apache.log4j.ConsoleAppender
log4j.appender.hb.layout=org.apache.log4j.PatternLayout
And my log4j2.xml:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<File name="File" fileName="ProtScannerLog.log" append="true">
<PatternLayout pattern="%d %t %-5p %c{2} - %m%n"/>
</File>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="debug">
<AppenderRef ref="Console" level="info" />
<AppenderRef ref="File" level="error" />
</Root>
</Loggers>
</Configuration>
When I run I get the log file in the directory I am running my code from, but it is blank. I see the correct messages in the console. I also would like to have this log file placed in C:\Users\username, but I am having trouble specifying that location. Any help would be much appreciated. Thanks in advance.

It supposed to be comment, but I don't have a reputation so have to post it this way :)
I've just copy pasted your config and it generated the ProtScannerLog.log file with several lines in.
So it definitely not log4j2.properties config issue.
Regarding the location of the file I can suggest to replace:
property.filename = logs
by
property.filename = C:\\Users\\username
And then refer to the property in "appender.file.fileName" definition:
appender.file.fileName=${filename}\\ProtScannerLog.log
It would create the file under any folder you specify.

Logger issue in Spring Boot

I have implemented Logging in Spring Boot application by using log4j2.properties file.
Please find the code as in below reference url:
Spring Boot - log4j2.properties creating log files but not writing the logs in file
The console logging is working and also file creating and one of the log is writing into the file but others are not writing into the file.
Please find the differences of loggers as printing in console as below:
[INFO ] 2018-08-06 11:48:05.609 [restartedMain] DemoApplication - Logger enabled: Entering main //this log is writing into file.
2018-08-06 11:48:14.211 INFO 10788 --- [ restartedMain] c.j.c.DemoApplication : **** Demo Application Started *****// this is not writing into file.
but for both using log.info to print the loggers.
Can anyone please help on this.

You have to carefully check your log4j2.properties file. I have tested with your example and following configuration works just fine:
name=PropertiesConfig
appenders = console, file
appender.console.type = Console
appender.console.name = STDOUT
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = [%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
appender.file.type = File
appender.file.name = LOGFILE
appender.file.fileName=demo.log
appender.file.layout.type=PatternLayout
appender.file.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
loggers=file
logger.file.name=com.testsexample.test5
logger.file.level = debug
logger.file.appenderRefs = file
logger.file.appenderRef.file.ref = LOGFILE
rootLogger.level = debug
rootLogger.appenderRefs = stdout
rootLogger.appenderRef.stdout.ref = STDOUT
Main class is the following (package name should correspond logger.file.name property in log4j2.properties):
package com.testsexample.test5;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class Test5Application {
private final static Logger LOG = LogManager.getLogger(Test5Application.class);
public static void main(String[] args) {
LOG.info("Logger enabled: Entering main \n\n");
SpringApplication.run(Test5Application.class, args);
LOG.info("**** Demo Application Started *****");
}
}
Project structure is:
Strange, but I have reproduced your issue after several relaunches. Please try to replace log4j2.properties with following log4j2.xml - the problem was gone with xml configuration
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
<Properties>
<Property name="log-path">logs</Property>
<Property name="LOG_PATTERN">
[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
</Property>
</Properties>
<Appenders>
<Console name="ConsoleAppender" target="SYSTEM_OUT">
<PatternLayout pattern="${LOG_PATTERN}"/>
</Console>
<File name="FileAppender" fileName="demo.log">
<PatternLayout>
<pattern>
[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
</pattern>
</PatternLayout>
</File>
</Appenders>
<Loggers>
<Root level="INFO">
<AppenderRef ref="FileAppender"/>
<AppenderRef ref="ConsoleAppender"/>
</Root>
</Loggers>
</Configuration>
For daily rolling appender it will be:
<RollingFile name="FileAppender" fileName="demo.log" filePattern="demo %d{yyyy-MM-dd}.log">
<PatternLayout>
<pattern>
[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
</pattern>
</PatternLayout>
<Policies>
<TimeBasedTriggeringPolicy interval="1" modulate="true"/>
</Policies>
<DefaultRolloverStrategy></DefaultRolloverStrategy>
</RollingFile>

log4j2 Dynamic log file name in Java

I have simple question.
How to have log file name dynamically supplied from code?
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="warn" name="MyApp" packages="">
<Appenders>
<RollingFile name="RollingFile" fileName="${logfilename}.log"
filePattern="logs/$${date:yyyy-MM}/app-%d{yyyy-MM-dd-HH}-%i.log.gz">
<PatternLayout>
<Pattern>%d %p %c{1.} [%t] %m%n</Pattern>
</PatternLayout>
<Policies>
<TimeBasedTriggeringPolicy interval="6" modulate="true"/>
<SizeBasedTriggeringPolicy size="250 MB"/>
</Policies>
</RollingFile>
</Appenders>
<Loggers>
<Root level="error">
<AppenderRef ref="RollingFile"/>
</Root>
</Loggers>
Here file name is logs/app.log.
How to make it dynamic with date and time appended as well in file name? Though pattern is applied but it doesn't work.
Here logs is the directory which log4j library automatically creates, can it be dynamic as well?
EDIT In parameter fileName I have placed ${logfilename}.log and setting system property as below:
System.setProperty("logfilename", "a_cool_logname");
Now it is creating file with name ${logfilename}.log which is definitely not required.
Thanks

**Property File Look like this **
log4j.rootLogger=DEBUG, FA
#Console Appender WE WRE NOT USING IT
log4j.appender.CA=org.apache.log4j.ConsoleAppender
log4j.appender.CA.layout=org.apache.log4j.PatternLayout
log4j.appender.CA.layout.ConversionPattern=%d{dd MM yy HH:mm} %-5p %m%n
#File Appender
log4j.appender.FA=org.apache.log4j.FileAppender
log4j.appender.FA.File=${fName}
#log4j.appender.FA.MaxFileSize=5MB
#log4j.appender.FA.MaxBackupIndex=3
log4j.appender.FA.layout=org.apache.log4j.PatternLayout
log4j.appender.FA.layout.ConversionPattern=%d{dd MM yy HH:mm} %8p %10m%n
# Set the logger level of File Appender to WARN
log4j.appender.FA.Threshold = INFO
log4j.appender.FA.Threshold = DEBUG
**And set Properties in JAVA **
System.setProperty("fName", "d:\\siemens\\" + getDateTime() + c.getSimpleName() +".log");
PropertyConfigurator.configure("log4j.properties");
let me know if u need further query thanks

How configure SLF4J underlying configuration file location [duplicate]

I have the followed imports:
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
and the following instantiation:
private static Logger logger = LoggerFactory.getLogger(Test.class);
and the following in my Main method:
logger.info("SOME MESSAGE: ");
However, I'm not able to find the output anywhere. All I see is that in my console there is:
21:21:24.235 [main] INFO some_folder.Test - SOME MESSAGE:
How do I locate the log file?
Note that the following are on my build path:
slf4j-api-1.7.5.jar
slf4j-log4j12-1.6.4.jar
I read the answer to similar questions but nobody actually says how to fix the problem.

slf4j is only an API. You should have a concrete implementation (for example log4j). This concrete implementation has a config file which tells you where to store the logs.
When slf4j catches a log messages with a logger, it is given to an appender which decides what to do with the message. By default, the ConsoleAppender displays the message in the console.
The default configuration file is :
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<!-- By default => console -->
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="error">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>
If you put a configuration file available in the classpath, then your concrete implementation (in your case, log4j) will find and use it. See Log4J documentation.
Example of file appender :
<Appenders>
<File name="File" fileName="${filename}">
<PatternLayout>
<pattern>%d %p %C{1.} [%t] %m%n</pattern>
</PatternLayout>
</File>
...
</Appenders>
Complete example with a file appender :
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<File name="File" fileName="${filename}">
<PatternLayout>
<pattern>%d %p %C{1.} [%t] %m%n</pattern>
</PatternLayout>
</File>
</Appenders>
<Loggers>
<Root level="error">
<AppenderRef ref="File"/>
</Root>
</Loggers>
</Configuration>

As already mentioned its just a facade and it helps to switch between different logger implementation easily. For example if you want to use log4j implementation.
A sample code would looks like below.
If you use maven get the dependencies
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.6</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
Have the below in log4j.properties in location src/main/resources/log4j.properties
log4j.rootLogger=DEBUG, STDOUT, file
log4j.appender.STDOUT=org.apache.log4j.ConsoleAppender
log4j.appender.STDOUT.layout=org.apache.log4j.PatternLayout
log4j.appender.STDOUT.layout.ConversionPattern=%5p [%t] (%F:%L) - %m%n
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=mylogs.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{dd-MM-yyyy HH:mm:ss} %-5p %c{1}:%L - %m%n
Hello world code below would prints in console and to a log file as per above configuration.
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class HelloWorld {
public static void main(String[] args) {
Logger logger = LoggerFactory.getLogger(HelloWorld.class);
logger.info("Hello World");
}
}

It does not write to a file by default. You would need to configure something like the RollingFileAppender and have the root logger write to it (possibly in addition to the default ConsoleAppender).

The log file is not visible because the slf4j configuration file location needs to passed to the java run command using the following arguments .(e.g.)
-Dlogging.config={file_location}\log4j2.xml
or this:
-Dlog4j.configurationFile={file_location}\log4j2.xml