使用 joda-time 可能如下所示：

DateTime dt = new DateTime(DateTimeZone.forID("GMT"));
System.out.println(dt); // 5 am
dt = dt.withZone(DateTimeZone.forID("EET"));
System.out.println(dt); // 8 am

请注意， Timestamp 没有时区的概念，所以它不适合代表它。

Note that Timestamp has no notion of Timezone so it is not suitable for representing it.

您的解决方案将具有良好的运行时间，因为它是O（1）。很难阅读。

Your solution will have a good running time, since it's O(1). It's harder to read though.