Java logback + slf4j instead of log4j + slf4j

Inspiration 
1 - 10 Reasons to switch to logback
2 - LOGBack: Evolving Java Logging
3 - Clean code, clean logs: easy to read, easy to parse (10/10) Series, (Tomasz Nurkiewicz, 2010)


Tweets about "logback slf4j"

[STEP 1] add slf(Simple Logging Facade)4j and logback dependencies


<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.6.6</version>
</dependency>

<dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-classic</artifactId>
    <version>1.0.9</version>
</dependency>


[STEP 2] configure logback.xml to src/main/resources
Don't forget to add <appender> to <root>, each appender thus referenced is added to the <root> logger.

logback.xml would look like the folloing one.

<?xml version="1.0" encoding="UTF-8"?>

<configuration>

    <!--
        WARN or higher goes to STDOUT (catalina.out)
    -->

<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">

   <encoder>

     <pattern>

        %d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n

      </pattern>

    </encoder>

</appender>

<appender name="eccountFileAppender"

class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${catalina.base}/logs/eccount.log</file>
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<Pattern>%d{yyyy-MM-dd_HH:mm:ss.SSS} [%thread] %-5level %logger{36} -
%msg%n
</Pattern>
</encoder>

<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${catalina.base}/logs/eccount.%d{yyyy-MM-dd}.%i.gz
</fileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy
class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MB</maxFileSize>
</timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>10</maxHistory>
</rollingPolicy>
</appender>



<!-- additivity=false ensures eccountlog data only goes to the analytics log -->
<logger name="eccountlogger" level="ALL" additivity="false">
        <level value="INFO"/>
<appender-ref ref="eccountFileAppender" />
</logger>


<root level="INFO">
<appender-ref ref="STDOUT" />
<appender-ref ref="eccountFileAppender" />
</root>

</configuration>



[STEP 3] implement org.slf4j.Logger

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class RequestManager implements IRequestManager, MessageSourceAware {
       private static Logger logger =          LoggerFactory.getLogger("eccountlogger"); //log will then reflected to its corresponding <appender-ref/>
  
  @override
  public void process(){
      logger.error("This is my {}", new Object[]{ arg, e});
  }
}


References
SLF4J with Logback in a Maven Project, http://blog.mograbi.info/2013/03/slf4j-with-logback-in-maven-project.html

Logback using SLF4J Hello World Example, http://www.srccodes.com/p/article/21/logback-using-slf4j-hello-world-example

http://stackoverflow.com/a/2489569/432903

http://itsmevandana.wordpress.com/2012/12/27/setting-up-logging-in-an-web-based-application-using-logback-xml/

http://stackoverflow.com/questions/13685084/grails-2-1-1-logback-integration/