使用java将当前GMT时间转换为CST时区

我正在尝试使用 JDK8 将当前 GMT 时间转换为 CST 时间。但我的代码总是为两个时区返回相同的时间。我还验证了 getAvailableIDs() 具有“CST”。

                Calendar cal = Calendar.getInstance();
            TimeZone timeZone = TimeZone.getTimeZone("GMT");
            cal.setTimeZone(timeZone);

            // System.out.println("GMT time = " + cal.getTime());

            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            sdf.setTimeZone(timeZone);
            String gmtDateStr = sdf.format(cal.getTime());
            System.out.println("Formatted GMT time = " + gmtDateStr);

            // To CST
            SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            TimeZone cst = TimeZone.getTimeZone("CST");
            sdf2.setTimeZone(cst);
            Date cstDate = sdf2.parse(gmtDateStr);

            // System.out.println("PARSED CST DATE = " + cstDate);

            Calendar cal2 = new GregorianCalendar();
            cal2.setTime(cstDate);
            cal2.setTimeZone(cst);
            String cstDateStr = sdf2.format(cal2.getTime());

            // System.out.println("cal2 time = " + cal2.getTime());
            System.out.println("FORMATTED CST DATE = " + cstDateStr);

这里有什么问题吗？有人能给我一个答案吗？

您不必执行所有这些转换即可获得您首选时区的时间。您可以简单地执行以下操作..

        Calendar cal = Calendar.getInstance();
        TimeZone timeZone = TimeZone.getTimeZone("GMT");
        cal.setTimeZone(timeZone);

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        sdf.setTimeZone(timeZone);
        String gmtDateStr = sdf.format(cal.getTime());
        System.out.println("Formatted GMT time = " + gmtDateStr);

        // To CST
        SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        TimeZone cst = TimeZone.getTimeZone("CST");
        sdf2.setTimeZone(cst);

        System.out.println("FORMATTED CST DATE = " + sdf2.format(cal.getTime()));