Hello,

I hit the same problem a while ago, what I did was  

List<URL> classpath = m_project.getRuntimeClasspathElements();

where m_project is of course the parameter ${project} (MavenProject).

>From there, it's no problem to construct an UrlClassLoader and run a new
thread with it as context class loader. 

Yours,

David Bernhard

> -----Original Message-----
> From: upstreamnet [mailto:[EMAIL PROTECTED] 
> Sent: 23 June 2008 08:39
> To: [email protected]
> Subject: Do maven plugin (mojo) developers have access to a 
> classloader based on ${project.artifacts}, or do we need to 
> build it up ourselves?
> 
> 
> Hi, I'm interested in using the spring beandoc mojo, but it 
> has some issues,
> which I believe were previously touched on  in this
> forum.
> 
> Basically, my problem is that the spring bean doc plugin is 
> failing for me
> when i try to process
> spring beans that use imports the reference other bean files 
> by class path.  
>   e.g.:
> 
>    <import resource="classpath:applicationContext-dao.xml" />
> 
> 
> This seems to be a result of the fact that when the mojo executes it's
> Thread's currentContextClassLoader 
> doesn't have references to the artifacts (jars) that are used 
> at compile
> time.
> 
> There seems to be  a bug related to this issue that was 
> closed as wontFix
> 
>       http://jira.codehaus.org/browse/MNG-697
> 
> The question which launched the original thread of discussion 
> (which I think
> was sent by the original developer of the spring bean doc 
> mojo) is here:
> 
>       
> http://www.nabble.com/-m2--plugin-classpath-question-to662848.
html#a662848
> 
> 
> The response to the question was basically 
>       >>You can get the JARs for the project's artifacts using the
> ${project.artifacts} expression.
> 
> 
> I found some plugin code (at the URL below)
> that seems to (more or less) follow this approach... 
> 
> http://metagenome.ncl.ac.uk/websvn/filedetails.php?repname=flu
xion&path=%2Ftrunk%2Fstack%2Fgenerate-beans-plugin%2Fsrc%2Fmain%>
2Fjava%2Forg%2Fcomparagrid%2Ffluxion%2Fplugins%2Fbeangen%2FGen
> erateBeansMojo.java&rev=532&sc=1
> 
> 
> I guess I'll fix the spring bean doc plugin using this 
> approach, unless
> someone suggests a better one.  
> 
> 
> The code that I'm planning to write to do mostly borrows from
> GenerateBeansMojo.java (in the link above)..
> Any comments or suggestions are most welcome>>>
> 
> 
> class  MyMojo.....  extends AbstractMojo {
> 
>   /**
>    * The set of artifact artifacts
>    *
>    * @parameter expression = "${project.artifacts}"
>    * @readonly
>    */
>   private Collection artifacts;
> 
> 
> 
>   /**
>    * Resolve Maven artifacts from "${project.artifacts}" and 
> set up the
> current
>    * context class loader to load the classes from these artifacts. 
> 
>    *  Calling class should restore original classloader... this method
> should probably
>    *  return the original (before the current threads' 
> context class loader
> was changed)
>    * 
>    * <p/>
>    * NOTE that this seems to be necessary to work around a 
> maven bug.  The
>    * plugin should have these dependencies available to it's 
> classloader,
> but
>    * the classloader seems to be persistent from previous 
> invocations, and
> as
>    * such I'm having to load the classes myself.
>    *
>    * @throws MojoExecutionException
>    */
>   private void resolveDependencies() throws MojoExecutionException
>   {
>     try
>     {
>       List<URL> allURLs = new ArrayList<URL>();
>       for (Object o : artifacts)
>       {
>         Artifact artifact = (Artifact) o;
>         allURLs.add(artifact.getFile().toURL());
> 
>       }
> 
>       // TO FIX CLASSLOADER BUG
>       // Set up the classloader to load from all declared 
> artifacts in this
> project
>       URL[] urls = new URL[allURLs.size()];
>       urls = allURLs.toArray(urls);
>       URLClassLoader loader = new URLClassLoader(urls,
> Thread.currentThread().getContextClassLoader());
>       Thread.currentThread().setContextClassLoader(loader);
> 
> //            // TODO - this fix is definately NOT a 
> desirable solution
> //            // the plugin classloader will gradually 
> accumulate more and
> more redundant stuff
> //            // but it works for now, although there are 
> duplicates being
> loaded and it isn't right!
>     }
>     catch (MalformedURLException e)
>     {
>       throw new MojoExecutionException(
>               "Unable to access " + classDir.getAbsolutePath());
>     }
> 
>   }
> 
> 
>       thanks -- Chris
> 
> -- 
> View this message in context: 
> http://www.nabble.com/Do-maven-plugin-%28mojo%29-developers-ha
ve-access-to-a-classloader-based-on-%24%7Bproject.artifacts%7D%>
2C-or-do-we-need-to-build-it-up-ourselves--tp18063356p18063356.html
> Sent from the Maven - Users mailing list archive at Nabble.com.
> 
> 
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