不同时区的时间问题

 public static void main(String[] args) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
        Calendar calendar = Calendar.getInstance();
        sdf.setTimeZone(TimeZone.getTimeZone("America/Los_Angeles"));
        System.out.println("Los_Angeles :"+sdf.format(calendar.getTime()));
        sdf.setTimeZone(TimeZone.getTimeZone("Asia/Shanghai"));
        System.out.println("Shanghai: "+sdf.format(calendar.getTime()));
    }