code: @Override
      public AsyncContext startAsync(ServletRequest arg0, ServletResponse arg1) {
          try {
              collaborator.preInvoke(componentMetaData);
              return request.startAsync(arg0, arg1);
          } finally {
              collaborator.postInvoke();
          }
      }
docs: /*
  (non-Javadoc)
  
  @see javax.servlet.ServletRequest#startAsync(javax.servlet.ServletRequest, javax.servlet.ServletResponse)