springboot log4j logging | log4j | log4j with springboot | springboot log4j demo | okay java

springboot log4j logging | log4j with springboot | springboot log4j demo | okay java
Special thanks to a super subscriber Sasi K :)

Download the source code

#Log4J configuration

# Log file path

Log4j
Log4j is a fast, reliable and flexible logging framework which is written in java. It is an open-source logging API for java.

Log4j Architecture
Log4j follows a layered architecture where each layer is used to provide different objects to perform different tasks.

Logger object
is used to enable the log4j in java class
also responsible for taking logging information
These methods are:
debug()
info()
warn()
error()
fatal()

Appender object(Interface)
The Appender object is responsible for publishing logging information to various preferred destinations such as a file, database, console, Unix Syslog, etc.
1. FileAppender –
A. RollingFileAppender
B. DailyRollingFileAppender
2. ConsoleAppender
3. JDBCAppender
4. SMTPAppender
5. SocketAppender
6. SyslogAppender
7. TelnetAppender
8. WriterAppender

Layout object
is used to format logging information in different styles (human-readable and reusable.).
SimpleLayout : level – logging info
PatternLayout : format the output based on conversion pattern specified
HTMLLayout : It formats the output as an HTML table.
XMLLayout : xml format

Log Level Description
ALL This level turns on all levels of logging. It includes the custom logging levels that you have defined. Once this one is configured and the levels are not considered at all, then all the appenders will start pouring the log events in log files.
DEBUG Debug is used a lot for debugging the application at development time. Every log message will appear to log files once this level is set. It basically belongs to developers.
INFO The INFO logging level is used to record messages about routine application operation. In real-time, system administrators watch the info logs to ensure what's happening on the system right now, and if there is any problem in normal flow.
WARN WARN log level is used to indicate that you might have a problem and that you've detected an unusual situation. Maybe you were demanding to invoke a service, and it failed a couple of times before connecting on an automatic retry. It is unexpected and unusual, but no real harm was done, and it's not known whether the issue will persist or recur. Someone should investigate warnings.
ERROR The ERROR log level is used to denote a serious problem that you must have to investigate immediately. Not as serious as FATAL, but still a problem. It simply means that your application has met really undesired state. For example, unexpected formatted input, database unavailability.
FATAL The FATAL log level, like ERROR, designates a problem. But unlike ERROR, it designates a very serious error event. You will not consider their presence very much on a normal day, but once they appear, it signals very bad news, even the application of death.
OFF This is the highest possible rank and is intended to turn off logging.
TRACE This has been recently introduced in version 1.2 and includes more information to debug level logs.

[vitthal_varakK]

Best channel for learning spring and java make more videos on spring rest.

[rakshitamhegde]

Hi !!, I have a question, my logs are not printing in the production environment, but they are being printed in stage environment.. all timer logs are appearing, what could be the reason?

[sasikala_chowdary]

Thank you. Very usefull.
I Have some questions
1.log4j and log4j2 both have same functionality?
can we use anyone of that?
2.instead of using properties file how can we use xml configuration file ?
Is there any changes we need to do if we we want to use xml configuration.

[undercrackers]

Unfortunately, my project includes a number of library JARs and is deployed remotely. This completely changes the game. The library JARs are packaged into on deployment JAR and log4j2 outputs all logging for those as well as my application. In addition it is not clear where the log4j2 configuration file should be deployed. I don't want it in a project resources folder because then it is packaged into the deployable JAR and I cannot reconfigure my logging. Also, whether I put the log4j2 configuration file in /home/user/application or home/user/application/dist makes no difference. The deployed JAR cannot find it when executed. I have tried working through the Apache documentation, but theoretical physics is probably easier to understand and certainly better presented. Under huge pressure to get the job done I am thinking of either writing something myself or looking for alternatives.

[jamshedakhter]

In different environmentst how we will give Log file path?

[padmasree]

Hi we are using spring boot java application, spring boot by default providing the log4j-api 2.12.2 jar and log4j-to slf4j jar files. We are not using only slf4j, and we didn't used these in pom.xml file, but safer we just added log 4j- 2.15 version jar. There will be any problem or Is there any alternate?