Java is reading the locale, timezone and encoding information (and perhaps more) from the system it is installed on.

This often brings bad surprises (brought me one just yesterday). Say your development and production servers are set to have TimeZone GMT+2. Then you deploy on a production server set to GMT. a 2-hour shift may not be easy to observe immediately. And although you can pass a TimeZone to your calendars, APIs might be instantiating calendars (or dates) using the default timezone.

Now, I know one should be careful with these settings, but are easy to miss, hence make programs more error-prone.

So, why doesn't Java have its own defaults - UTF-8, GMT, en_US (yes, I'm on non-en_US locale, but having it as default is fine). Applications could read the system settings via some API, if needed.

Thus programs would be more predictable.

So, what is the reason behind this decision?