TimeZone validation in Java

Question

I have a string, I need to check whether it is a standard time zone identifier or not. I am not sure which method I need to use.

String timeZoneToCheck = \"UTC\"         


        

Answer 1

If TimeZone.getAvailableIDs() contains ID in question, it's valid:

public boolean validTimeZone(String id) {
    for (String tzId : TimeZone.getAvailableIDs()) {
            if (tzId.equals(id))
                return true;
    }
    return false;
}

Unfortunately TimeZone.getTimeZone() method silently discards invalid IDs and returns GMT instead:

Returns:

the specified TimeZone, or the GMT zone if the given ID cannot be understood.