@Override
    public String toString(final StringBuilder builder) {
        try {
            val json = JsonValue.readJSON(statistics.toJson());
            val writer = new StringWriter();
            json.writeTo(writer, Stringify.FORMATTED);
            builder.append(writer);
        } catch (final Exception e) {
            LoggingUtils.error(LOGGER, e);
        }
        return builder.toString();
    }
This is {@link MongoDbCacheStatistics}.

@author Misagh Moayyed
@since 5.2.0
support/cas-server-support-mongo-monitor/src/main/java/org/apereo/cas/monitor/MongoDbCacheStatistics.java