title: Acceleo first steps to transform a BPEL file to Java classes
body: <p>I'm trying a transformation with Acceleo from BPEL to Java.
  I did 2 or 3 tutorials and all involved the use of UML input models, though I think I understood how I should deal with a bpel model and its bpel.ecore meta-model.</p>
  
  <p>Though, I'm having a problem on running a very easy transformation which should just generate a java file with the name of my BPEL process file.</p>
  
  <p>Here is my Acceleo generate.mtl file:</p>
  
  <pre><code>[comment encoding = UTF-8 /]
  [module generate('http:///org/eclipse/bpel/model/bpel.ecore')]
  
  [template public generateElement(aProcess : Process)]
  [comment @main /]
  [file (aProcess.name, false, 'UTF-8')]
  [/file]
  [/template]
  </code></pre>
  
  <p>and here the input .bpel file (just a part of it) :</p>
  
  <pre><code>&lt;!-- BPEL_sayHelloProcess BPEL Process [Generated by the Eclipse BPEL Designer] --&gt;
  &lt;!-- Date: Wed Jul 18 11:00:50 CEST 2012 --&gt;
  &lt;bpel:process name="BPEL_sayHelloProcess"
           targetNamespace="http://bpeltojava.uni"
           suppressJoinFailure="yes"
  ....
  ....
  &lt;/bpel:process&gt;
  </code></pre>
  
  <p>here is the error I get:</p>
  
  <blockquote>
    <p>The generation failed to generate any file because there are no model
    elements that matches at least the type of the first parameter of one
    of your main templates.  The problem may be caused by a problem with
    the registration of your metamodel, please see the method named
    "registerPackages" in the Java launcher of your generator. It could
    also come from a missing [comment @main/]  in the template used as the
    entry point of the generation.</p>
  </blockquote>
  
  <p>I'm using Eclipse Modeling Juno 4.2 and Acceleo 3.3.0
  Thank you :-)</p>