设置UTC时区在Android中不起作用

我正在尝试使用以下代码将毫秒时间值转换为UTC 12小时格式：

    public void updateDateAndTimeForMumbai(String value) {
            SimpleDateFormat outputTimeFormatter = new SimpleDateFormat("h:mm");
SimpleDateFormat outputDateFormatter = new SimpleDateFormat("dd/MM/yyyy");

            TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
            // Create a calendar object that will convert the date and time value in milliseconds to date.
            Calendar calendar = Calendar.getInstance(TimeZone.getTimeZone("UTC"));

            try {
                calendar.setTimeInMillis(Long.parseLong(value));
                Log.i("Scheduled date: " + outputDateFormatter.format(calendar.getTime()));
                Log.i("Scheduled time: " + outputTimeFormatter.format(calendar.getTime()));
                Log.i("Scheduled time Am/Pm: " + new SimpleDateFormat("aa").format(calendar.getTime()));

            } catch (NumberFormatException n) {
                //do nothing and leave all fields as is

            }

        }

此处value=“1479633900000”

---

我不知道问题出在哪里。

您需要显式使用DateFormat.setTimeZone（）以所需时区打印日期

outputDateFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));

请在执行以下操作后调用此选项：

SimpleDateFormat outputDateFormatter = new SimpleDateFormat("dd/MM/yyyy");

如果从服务器接收的时间不是UTC时间，则不应将日历实例设置为UTC。但只需直接设置日历时间即可。
除去

打电话

Calendar calendar = Calendar.getInstance();  

以下是最终代码的外观：

public void updateDateAndTimeForMumbai(String value) {
            SimpleDateFormat outputTimeFormatter = new SimpleDateFormat("h:mm");
            outputTimeFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
            SimpleDateFormat outputDateFormatter = new SimpleDateFormat("dd/MM/yyyy");
            outputDateFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));

            // Create a calendar object that will convert the date and time value in milliseconds to date.
            Calendar calendar = Calendar.getInstance();

            try {
                calendar.setTimeInMillis(Long.parseLong(value));
                Log.i("Scheduled date: " + outputDateFormatter.format(calendar.getTime()));
                Log.i("Scheduled time: " + outputTimeFormatter.format(calendar.getTime()));
                Log.i("Scheduled time Am/Pm: " + new SimpleDateFormat("aa").format(calendar.getTime()));

            } catch (NumberFormatException n) {
                //do nothing and leave all fields as is

            }

        }

---

它不起作用，我仍然得到同样的结果

Calendar calendar = Calendar.getInstance();  

public void updateDateAndTimeForMumbai(String value) {
            SimpleDateFormat outputTimeFormatter = new SimpleDateFormat("h:mm");
            outputTimeFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
            SimpleDateFormat outputDateFormatter = new SimpleDateFormat("dd/MM/yyyy");
            outputDateFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));

            // Create a calendar object that will convert the date and time value in milliseconds to date.
            Calendar calendar = Calendar.getInstance();

            try {
                calendar.setTimeInMillis(Long.parseLong(value));
                Log.i("Scheduled date: " + outputDateFormatter.format(calendar.getTime()));
                Log.i("Scheduled time: " + outputTimeFormatter.format(calendar.getTime()));
                Log.i("Scheduled time Am/Pm: " + new SimpleDateFormat("aa").format(calendar.getTime()));

            } catch (NumberFormatException n) {
                //do nothing and leave all fields as is

            }

        }