@Override
    public String toString(final StringBuilder builder) {
        if (this.name != null) {
            builder.append(this.name).append(':');
        }
        try (val formatter = new Formatter(builder)) {
            formatter.format("%.2f", this.size / BYTES_PER_MB);
        }
        builder.append("MB used, ");
        builder.append(getPercentFree()).append(" percent free, ");
        builder.append(this.evictions).append(" evictions");
        return builder.toString();
    }
Simple implementation of cache statistics.

@author Marvin S. Addison
@since 3.5.1
core/cas-server-core-monitor/src/main/java/org/apereo/cas/monitor/SimpleCacheStatistics.java