buf.append('{').append(escapeJsonKeyValue(DOC_ID_FIELD, docIdList.get(i))).append('}');
                }
            }
            buf.append(']');
            body = buf.toString();
            writeJsonResponse(HttpServletResponse.SC_OK, body);
        } catch (final WebApiException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Failed to process a favorites request.", e);
            }