[Log4j] How can I make my Java Web project use log4j?

Create a project:

Preparations for using log4j in log4j,

The first jar package, need to log4j-1.2.11.jar package, import to your own project;

2. Create the log4j. properties file and fill in the corresponding configuration. I have filled in two configurations: Console output and file output.

The configuration is as follows:

### Output log information to the console

### Log4j. appender. stdout = org. Apache. log4j. leleappender

### Print the information to system. Out

### Log4j. appender. stdout. Target = system. outlog4j. appender. stdout. layout = org. Apache. log4j. patternlayout

### Specify the output format: Display date and log information

### Log4j. appender. stdout. layout. conversionpattern = % d {yyyy-mm-dd hh: mm: SS} % m % N

### Output log information to the file F: \ log \ test. Log

### Log4j. appender. File = org. Apache. log4j. fileappender

### Specify the log output file name

### Log4j. appender. file. File = F: \ log \ test. loglog4j. appender. file. layout = org. Apache. log4j. patternlayout

### Specify the output format: Display date, log location, and log information

### Log4j. appender. file. layout. conversionpattern = % d {yyyy-mm-dd hh: mm: SS} % L % m % N

### Set priorities and output sources ###

### Set priority to debug

### Log4j. rootlogger = debug, stdout, file

Configuration complete! Write a test program !!!

Log4j. Java

Import org. Apache. log4j. Logger;

Public class log4j {

Public static void main (string [] ARGs ){

// Obtain the logger, which controls the log information

Logger logger = logger. getlogger (log4j. Class. getname ());

Try {

// Use the debug and info methods of the logger object to output log information

Logger. debug ("sets the instructor ID. ");

} Catch (illegalargumentexception ex ){

// Use the debug and info methods of the logger object to output log information

Logger.info (ex. getmessage ());

}

}

}

Test result: This is the output result of the console:

21:35:41 set the instructor number.

The file output is not easy to display. I will not display it here. Please try it on your own !!

And this is the related knowledge http://logging.apache.org/log4j/1.2/download.html of log4j.