java Timezone setDefault effects

Question

following How to store date/time and timestamps in UTC time zone with JPA and Hibernate I want to set my application default time zone to UTC. My app runs on tomcat on a lin

Answer 1

Would launching your app server with the java option -Duser.timezone=GMT do it for you?

Answer 2

The default timezone setting in java is kind of screwy. by default, if you set the default timezone, it will affect the entire jvm. however, if you are running with a SecurityManager, and the current security context is not allowed to set the default, then the TimeZone.setDefault() method will instead set a thread local value (so any other code running on the same thread will see this value as the default, but the rest of the jvm will be unaffected). i don't think there is a way to set the default just for you "application" unless you can narrow your application to a specific collection of threads (highly unlikely).