Updating your SDK or runtime environment for Daylight Saving Time changes
You can apply recent changes to Daylight Saving Time by using the IBM® Time Zone Update Utility for Java™ (JTZU).
About this task
Many countries around the world use a Daylight Saving Time (DST) convention. Typically, clocks move forward by 1 hour during the summer months to create more daylight hours during the afternoon and less during the morning. This practice has many implications, including the need to adjust system clocks in computer systems. Occasionally, countries change their DST start and end dates. These changes can affect the date and time functions in applications because the original start and end dates are programmed into the operating system and in Java software. To avoid this problem, you must update operating systems and Java installations with the new DST information.
The Olson time zone database is an external resource that compiles information about the time zones around the world. This database establishes standard names for time zones, such as "America/New_York", and provides regular updates to time zone information that can be used as reference data. To ensure that IBM developer kits and Runtime Environments contain up to date DST information, IBM incorporates the latest Olson time zone level into every updated release. To find out which Olson time zone level is included for a particular SDK or refresh, see Java SDK Olson time zone updates.
If a DST change has been introduced since the last IBM update of the SDK, you can use JTZU to directly update your Java installation. You can also use this tool to update your installation if you are unable to move straight to the latest SDK update. JTZU is available from IBM Support at the following link: Java SDK Time Zone Update Utility.