title: How to solve ERROR Mwe2Launcher: Couldn't find EClass for name
body: <p>I created a Xpand generator. In its src/ folder I've defined my model My.nn a template and a workflow.</p>
  
  <p>This is how my workflow.mwe2 file looks like:</p>
  
  <pre><code>module workflow.NeuralNetworksGenerator
  
  import org.eclipse.emf.mwe.utils.*
  
  var targetDir = "src-gen"
  var fileEncoding = "Cp1252"
  var modelPath = "src/model"
  
  Workflow {
      component = org.eclipse.xtext.mwe.Reader {
          // lookup all resources on the classpath
          //useJavaClassPath = true
  
          // or define search scope explicitly
          path = modelPath
  
          // this class will be generated by the xtext generator 
          register = org.xtext.example.neuralnetworks.NeuralNetworksStandaloneSetup {}
          load = {
              slot = "systems"
              type = "System"
          }
      }
  
      component = org.eclipse.xpand2.Generator {
          expand = "templates::Template::main FOREACH systems"
          outlet = {
              path = targetDir
          }
          fileEncoding = fileEncoding
      }
  }
  </code></pre>
  
  <p>When I'm trying to run this workflow.mwe2 file as MWE2 Workflow, I get the following errors:</p>
  
  <pre><code>0    INFO  AbstractExpressionsUsingWorkflowComponent - No meta models configured, using JavaBeans as default.
  75   ERROR Mwe2Launcher       - Problems running workflow workflow.NeuralNetworksGenerator: Couldn't find EClass for name 'System'.
  java.lang.RuntimeException: Problems running workflow workflow.NeuralNetworksGenerator: Couldn't find EClass for name 'System'.
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Runner.run(Mwe2Runner.java:99)
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Runner.run(Mwe2Runner.java:73)
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Runner.run(Mwe2Runner.java:64)
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Runner.run(Mwe2Runner.java:55)
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Launcher.run(Mwe2Launcher.java:74)
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Launcher.main(Mwe2Launcher.java:35)
  Caused by: org.eclipse.emf.mwe.core.WorkflowInterruptedException: Couldn't find EClass for name 'System'.
      at org.eclipse.xtext.mwe.SlotEntry.findEClasses(SlotEntry.java:135)
      at org.eclipse.xtext.mwe.SlotEntry.put(SlotEntry.java:91)
      at org.eclipse.xtext.mwe.AbstractReader.addModelElementsToContext(AbstractReader.java:95)
      at org.eclipse.xtext.mwe.Reader.invokeInternal(Reader.java:166)
      at org.eclipse.emf.mwe.core.lib.AbstractWorkflowComponent.invoke(AbstractWorkflowComponent.java:126)
      at org.eclipse.emf.mwe.core.lib.Mwe2Bridge.invoke(Mwe2Bridge.java:34)
      at org.eclipse.emf.mwe.core.lib.AbstractWorkflowComponent.invoke(AbstractWorkflowComponent.java:201)
      at org.eclipse.emf.mwe2.runtime.workflow.AbstractCompositeWorkflowComponent.invoke(AbstractCompositeWorkflowComponent.java:35)
      at org.eclipse.emf.mwe2.runtime.workflow.Workflow.run(Workflow.java:19)
      at org.eclipse.emf.mwe2.launch.runtime.Mwe2Runner.run(Mwe2Runner.java:97)
      ... 5 more
  </code></pre>
  
  <p>The example that I used to create my particularized workflow mwe2 file is taken from the Xpand reference manual.</p>
  
  <p>This is the list of plug-in dependencies from the MANIFEST.MF file:</p>
  
  <pre><code>Manifest-Version: 1.0
  Bundle-ManifestVersion: 2
  Bundle-Name: my.neuralnetworks.generator.project
  Bundle-SymbolicName: my.neuralnetworks.generator.project; singleton:=true
  Bundle-Version: 1.0.0
  Require-Bundle: org.eclipse.jdt.core;bundle-version="3.5.0",
   org.eclipse.xtend.profiler;resolution:=optional,
   org.apache.commons.logging,
   org.apache.log4j;resolution:=optional,
   com.ibm.icu;bundle-version="4.0.1",
   org.antlr.runtime;bundle-version="3.0.0",
   org.eclipse.core.runtime;bundle-version="3.5.0",
   org.eclipse.emf.mwe.utils;bundle-version="0.7.0",
   org.eclipse.emf.ecore.xmi;bundle-version="2.5.0",
   org.eclipse.jface.text;bundle-version="3.5.0",
   org.eclipse.xpand;bundle-version="0.7.0",
   org.eclipse.xtend;bundle-version="0.7.0",
   org.eclipse.xtend.typesystem.emf;bundle-version="0.7.0",
   org.eclipse.xtend.backend;bundle-version="1.0.0";resolution:=optional,
   org.eclipse.xtend.middleend.xpand;bundle-version="1.0.0";resolution:=optional,
   org.eclipse.xtend.middleend.xtend;bundle-version="1.0.0";resolution:=optional,
   neuralnetworks;bundle-version="1.0.0",
   org.xtext.example.neuralnetworks;bundle-version="1.0.0",
   org.eclipse.emf.ecore.xmi.source;bundle-version="2.7.0",
   org.eclipse.jface.text.source;bundle-version="3.7.0",
   org.antlr.runtime.source;bundle-version="3.2.0",
   org.antlr.runtime_3.1.b1;bundle-version="3.1.0",
   com.ibm.icu.source;bundle-version="4.4.2",
   org.eclipse.jdt.core.source;bundle-version="3.7.0",
   org.eclipse.emf.mwe2.launch;bundle-version="2.2.0"
  Bundle-RequiredExecutionEnvironment: J2SE-1.5
  Import-Package: nn
  </code></pre>
  
  <p>The <em>neuralnetworks</em> plug-in refers to my gmf project for my graphical editor where the metamodel is found and the <em>org.xtext.example.neuralnetworks</em> is the one corresponding to my text editor.</p>
  
  <p>The ecore file corresponding to the emf file does have the EClass System in it.</p>