code: public Resource getResource(String uriInContext) throws IOException
      {
          IOException ioe= null;
          Resource resource= null;
          try
          {
              resource= super.getResource(uriInContext);
              if (resource != null && resource.exists())
                  return resource;
          }
          catch (IOException e)
          {
              ioe= e;
          }
  
          String aliasedUri= getResourceAlias(uriInContext);
          if (aliasedUri != null)
              return super.getResource(aliasedUri);
  
          if (ioe != null)
              throw ioe;
  
          return resource;
      }
docs: /* ------------------------------------------------------------