TimeZone and Daylight Savings Time 2007

[Marilyn de Queiroz]

We ran into an issue and I wanted to give everyone a heads up. If the timezone is defined as EST, MST, or HST, the behavior has changed. These 3 used to flip back and forth from standard time to daylight savings time. With the DST patch, these three now stay on standard time constantly.

[Deepak Bala]

I believe it should move on to EDT from EST

[Marilyn de Queiroz]

It used to. But with the latest patch, it no longer moves.

[Jim Yingst]

Ah, finally. Seems to me that MST should mean MST, not MDT. It's unfortunate that Sun's JDKs supported such misleading terminology for so long.

Note that the API for TimeZone does say:

Three-letter time zone IDs

For compatibility with JDK 1.1.x, some other three-letter time zone IDs (such as "PST", "CTT", "AST") are also supported. However, their use is deprecated because the same abbreviation is often used for multiple time zones (for example, "CST" could be U.S. "Central Standard Time" and "China Standard Time"), and the Java platform can then only recognize one of them.

Programmers needing to retain the old behavior (assuming it's too much trouble to fix the time zone codes to something more appropriate) can follow the instructions in this Sun alert.