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https://issues.apache.org/jira/browse/LOG4J2-400?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13925030#comment-13925030
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Ralph Goers commented on LOG4J2-400:
------------------------------------

I don't know what it means to reorganize the appender classes into separate 
packages without affecting log4j-core.  Are you just talking about moving stuff 
around into different directories?  

Whatever you are thinking, I'd like to see the list of changes before they are 
actually done.  FWIW, with all the separate jars and packaging needed for OSGi 
I am beginning to regret ever wanting to support it.

> Provide Appender-Bundles
> ------------------------
>
>                 Key: LOG4J2-400
>                 URL: https://issues.apache.org/jira/browse/LOG4J2-400
>             Project: Log4j 2
>          Issue Type: Improvement
>          Components: Appenders, Core
>    Affects Versions: 2.0-beta9, 2.0-rc1
>         Environment: OSGi R4 / R5 (Apache Felix 4.x)
>            Reporter: Roland Weiglhofer
>            Priority: Critical
>              Labels: Appender, Core, Dependency, OSGi, PluginManager, 
> lightweight, optional
>             Fix For: 2.0
>
>
> Instead of deploying all appenders in the core fragment, it would be much 
> better if the customer can choose which appender he wants to provide. It's 
> easy to hive the appender off in a separate bundle fragment. The host bundle 
> is the API bundle. The Plugin Manager (core fragment) finds the deployed 
> appenders in the classpath of the host bundle. The PluginManager should parse 
> the class path in a separate thread (Startup-Hook) and only once at the start 
> of the host bundle, but not for each call (when a consumer bundle aquires a 
> logger). Make package-imports optional 
> (<Import-Package>*;resolution:=optional</Import-Package>)!!!!
> This reduces the number of dependencies and reduces the startup time of the 
> whole system.
> One possible solution for the Plugin Manager is to use the reflections plugin 
> during the maven build process. This plugin lists all classes of a project 
> within a xml file. This file can be marked as a bundle resource and is stored 
> within the appender bundle fragment. The idea is that each appender fragment 
> has its own class list. Because the bundle host (log4j2 core) sees all 
> resources of its fragments it can load these class lists at runtime. Thus, 
> the Plugin Manager gets only those appenders that are installed  within 
> deployed bundle fragements. The class list is created during the build 
> process, the plugin manager must not parse the classpath at runtime. Log4j2 
> uses a xml parser by default. An additional new dependency to a xml-parser 
> library is not required.
>         <plugin>
>         <groupId>org.reflections</groupId>
>         <artifactId>reflections-maven</artifactId>
>         <version>0.9.8</version>
>           <executions>
>             <execution>
>               <goals>
>                 <goal>reflections</goal>
>               </goals>
>             <phase>process-classes</phase>
>           </execution>
>         </executions>
>         <configuration>
>           
> <destinations>${project.basedir}/META-INF/reflections/${project.artifactId}-reflections.xml</destinations>
>         </configuration>
>       </plugin>



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