Q:

What does the SSS represent in the org.apache.log4j.helpers.ISO8601DateFormat?

The JavaDoc says:

Formats a Date in the format "yyyy-MM-dd HH:mm:ss,SSS" for example
  "1999-11-27 15:49:37,459".

Are they milliseconds from 000-999? The summary of the international standard date and time notation makes no mention of milliseconds.

A:

It formats Date. In Date formatting "SSS" pattern means milliseconds from 000 to 999, so you are correct.

