code: protected boolean isSamlSoapResponse(HttpResponse res) 
      {
          boolean isSamlSoap = false;
          if (res.getFirstHeader(HttpHeaders.CONTENT_TYPE) != null) {
              ContentType contentType = ContentType.parse(res.getFirstHeader(HttpHeaders.CONTENT_TYPE)
                      .getValue());
              isSamlSoap = MIME_TYPE_PAOS.equals(contentType.getMimeType());
          }
          return isSamlSoap;
      }
docs: Checks whether the HttpResponse is a SAML SOAP message
  @param res the HttpResponse to check
  @return true if the HttpResponse is a SAML SOAP message, false if not