logback with EJB3.1

Question

I am using logback/slf4j to handle logging in my application. Everything was working perfectly until I started using EJBs. Once I added a stateless EJB to my app, the logger

Answer 1

This looks very close to the problem described in this thread and I suspect a similar class loading issue. Because of the way logback loads logback.xml (more precisely the way it retrieves a ClassLoader to do so), it may fail at picking up its configuration file and fall back on a default BasicConfiguration.

Not sure how you package your code but the suggested workaround is to include the logback.xml in a EAR lib. If you aren't using an EAR packaging, try to identify the class loader used to see where to put the logback.xml file.

At the end, this might be a problem in logback. Didn't check their issue tracker though.

Update: If you use a war packaging, try to configure GlassFish to use firstly the child classloaders before to delegate. In the sun-web.xml:

---

Update: I did a little test on my side and... I cannot reproduce your problem. I've created a project for a Java EE 6 webapp which has the following structure:

$ tree sample
sample
|-- pom.xml
`-- src
    `-- main
        |-- java
        |   `-- com
        |       `-- stackoverflow
        |           `-- q2418355
        |               |-- SimpleEJB.java
        |               `-- SimpleServlet.java
        |-- resources
        |   `-- logback.xml
        `-- webapp
            |-- META-INF
            |   `-- MANIFEST.MF
            |-- WEB-INF
            |   `-- lib
            `-- index.jsp

My pom.xml looks like:

  4.0.0
  com.stackoverflow.q2418355
  sample
  1.0-SNAPSHOT
  war
  sample Maven Webapp
  http://maven.apache.org
  
    
      javax
      javaee-api
      6.0
      provided
    
    
      junit
      junit
      4.7
      test
    
    
      ch.qos.logback
      logback-classic
      0.9.18
    
    
      org.slf4j
      slf4j-api
      1.5.11
    
  
  
    
      
        org.apache.maven.plugins
        maven-compiler-plugin
        2.0.2
        
          1.6
          1.6
        
      
      
        org.apache.maven.plugins
        maven-war-plugin
        2.1-beta-1
        
          false
        
      
    
    sample
  

The code for SimpleEJB.java is:

package com.stackoverflow.q2418355;

import javax.ejb.Stateless;

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

@Stateless
public class SimpleEJB {
    private static Logger logger = LoggerFactory.getLogger(SimpleEJB.class);

    public String sayHello(String name) {
        logger.debug(">> sayHello()");
        logger.debug("<< sayHello()");
        return "Hello " + name + "!!!";
    }
}

The code for SimpleServlet.java is:

package com.stackoverflow.q2418355;

import java.io.IOException;
import java.io.PrintWriter;

import javax.ejb.EJB;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(urlPatterns = { "/SimpleServlet" })
public class SimpleServlet extends HttpServlet {
    @EJB
    SimpleEJB bean;

    private static Logger logger = LoggerFactory.getLogger(SimpleServlet.class);

    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
        logger.debug(">> doGet()");
        PrintWriter out = response.getWriter();
        out.println("");
        out.println("
Serving at: " + request.getContextPath() + "
");
        out.println("
Invoking EJB: " + bean.sayHello("Duke") + "
");
        out.println("");
        logger.debug("<< doGet()");
    }
}

The code for index.jsp is:

Hello World!
Invoke the Servlet by clicking here.

And my logback.xml looks like:

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

  
    /tmp/logs/testFile.log
    true

    
      %-4relative [%thread] %-5level %logger{35} - %msg%n
    
  

  

  
    
    
  

My logback.xml gets propertly loaded and I get the following trace (taken from my log file) when invoking the servlet:

10913 [http-thread-pool-8080-(1)] DEBUG com.stackoverflow.q2418355.SimpleServlet - >> doGet()
10928 [http-thread-pool-8080-(1)] DEBUG com.stackoverflow.q2418355.SimpleEJB - >> sayHello()
10928 [http-thread-pool-8080-(1)] DEBUG com.stackoverflow.q2418355.SimpleEJB - << sayHello()
10932 [http-thread-pool-8080-(1)] DEBUG com.stackoverflow.q2418355.SimpleServlet - << doGet()

I did also try with the EJB packaged in its own JAR and deployed in WEB-INF/lib and get the same result, it just works. Can you spot any obvious difference? Maybe upload a simplified version of your app (will very likely be required for the bug report BTW).

I am running GlassFish v3 under Eclipse 3.5 (with the GlassFish v3 plugin).