@Override
  public void startContextElement(String name, Attributes attributes)
      throws org.xml.sax.SAXException {
    String id = attributes.getValue("id");
    String className = attributes.getValue("class");

    if (!checkNonEmpty(className)) {
      throw new org.xml.sax.SAXException("class Tag without any mainDefinition defined");
    }

    proActiveDescriptor.createMainDefinition(id);

    proActiveDescriptor.setMainDefined(true);
    proActiveDescriptor.mainDefinitionSetMainClass(className);
  }
    @Override
    public void startContextElement(String name, Attributes attributes)
        throws org.xml.sax.SAXException {
      String arg = attributes.getValue("value");

      // System.out.println("enter in a arg node : " + arg);
      if (!checkNonEmpty(arg)) {
        throw new org.xml.sax.SAXException("value Tag without any arg defined");
      }

      proActiveDescriptor.mainDefinitionAddParameter(arg);
    }
    @Override
    public void startContextElement(String name, Attributes attributes)
        throws org.xml.sax.SAXException {
      String virtualNode = attributes.getValue("value");

      if (!checkNonEmpty(virtualNode)) {
        throw new org.xml.sax.SAXException("value Tag without any mapToVirtualNode defined");
      }

      VirtualNodeInternal vn = proActiveDescriptor.createVirtualNode(virtualNode, false, true);

      proActiveDescriptor.mainDefinitionAddVirtualNode(vn);
    }