b.append('"').append(StringEscapeUtils.escapeJson(c.getName())).append("\":{");
            append(b, "count", () -> c.getCollectionCount()).append(',');
            append(b, "time", () -> c.getCollectionTime().getMillis()).append('}');
            return b.toString();
        }).collect(Collectors.joining(",")));
        buf.append("},");
        final Threads threads = jvmStats.getThreads();
        buf.append("\"threads\":{");

            }
            if (fieldSet.contains(TASK_MAX_WAIT_TIME_IN_QUEUE_IN_MILLIS)) {
                builder.field(TASK_MAX_WAIT_TIME_IN_QUEUE_IN_MILLIS, response.getTaskMaxWaitingTime().getMillis());
            }
            if (fieldSet.contains(ACTIVE_SHARDS_PERCENT_AS_NUMBER)) {
                builder.field(ACTIVE_SHARDS_PERCENT_AS_NUMBER, response.getActiveShardsPercent());
            }