public void visitMetaInfResource(WebAppContext context, Resource dir) {
   Collection<Resource> metaInfResources =
       (Collection<Resource>) context.getAttribute(MetaInfConfiguration.METAINF_RESOURCES);
   if (metaInfResources == null) {
     metaInfResources = new HashSet<Resource>();
     context.setAttribute(MetaInfConfiguration.METAINF_RESOURCES, metaInfResources);
   }
   metaInfResources.add(dir);
   // also add to base resource of webapp
   Resource[] collection = new Resource[metaInfResources.size() + 1];
   int i = 0;
   collection[i++] = context.getBaseResource();
   for (Resource resource : metaInfResources) collection[i++] = resource;
   context.setBaseResource(new ResourceCollection(collection));
 }
  /**
   * @param context
   * @param descriptor
   * @param node
   */
  public void visitContextParam(WebAppContext context, Descriptor descriptor, XmlParser.Node node)
      throws Exception {
    String name = node.getString("param-name", false, true);
    String value = node.getString("param-value", false, true);
    List<String> values = new ArrayList<>();

    // extract values
    switch (name) {
      case ServletContext.ORDERED_LIBS:
      case AnnotationConfiguration.CONTAINER_INITIALIZERS:
      case MetaInfConfiguration.METAINF_TLDS:
      case MetaInfConfiguration.METAINF_RESOURCES:
        context.removeAttribute(name);

        QuotedStringTokenizer tok = new QuotedStringTokenizer(value, ",");
        while (tok.hasMoreElements()) values.add(tok.nextToken().trim());

        break;

      default:
        values.add(value);
    }

    // handle values
    switch (name) {
      case ServletContext.ORDERED_LIBS:
        {
          List<Object> libs = new ArrayList<>();
          Object o = context.getAttribute(ServletContext.ORDERED_LIBS);
          if (o instanceof Collection<?>) libs.addAll((Collection<?>) o);
          libs.addAll(values);
          if (libs.size() > 0) context.setAttribute(ServletContext.ORDERED_LIBS, libs);

          break;
        }

      case AnnotationConfiguration.CONTAINER_INITIALIZERS:
        {
          for (String i : values)
            visitContainerInitializer(
                context,
                new ContainerInitializer(Thread.currentThread().getContextClassLoader(), i));
          break;
        }

      case MetaInfConfiguration.METAINF_TLDS:
        {
          List<Object> tlds = new ArrayList<>();
          String war = context.getBaseResource().getURI().toString();
          Object o = context.getAttribute(MetaInfConfiguration.METAINF_TLDS);
          if (o instanceof Collection<?>) tlds.addAll((Collection<?>) o);
          for (String i : values) {
            Resource r = Resource.newResource(i.replace("${WAR}/", war));
            if (r.exists()) tlds.add(r.getURL());
            else throw new IllegalArgumentException("TLD not found: " + r);
          }

          if (tlds.size() > 0) context.setAttribute(MetaInfConfiguration.METAINF_TLDS, tlds);
          break;
        }

      case MetaInfConfiguration.METAINF_RESOURCES:
        {
          String war = context.getBaseResource().getURI().toString();
          for (String i : values) {
            Resource r = Resource.newResource(i.replace("${WAR}/", war));
            if (r.exists()) visitMetaInfResource(context, r);
            else throw new IllegalArgumentException("Resource not found: " + r);
          }
          break;
        }

      default:
    }
  }