isBefore

Returns true if this occurs before that, and returns false otherwise.

If the value of either this or that is not valid, then this method returns false.

Standard assumptions for Comparable are not guaranteed to hold. For example, it is entirely possible that a == b, a.isBefore(b), b.isBefore(a) are all false at the same time; for example if a and b have different invalid values. For this reason, Timestamp does not implement Comparable. However, if this and that both have valid values, then these strange situations do not occur.