Why does subtracting epoch milliseconds (year 1927) give a strange result?

Hello everyone! I'm a beginner in Java and I've encountered a very strange problem when working with dates. I'm trying to calculate the difference in milliseconds between two moments in time in 1927, but the result is not what I expect.\n\nHere's my code:\n\n```java\nimport java.text.SimpleDateFormat;\nimport java.util.Date;\nimport java.util.TimeZone;\n\npublic class StrangeDate {\n public static void main(String[] args) throws Exception {\n SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");\n sdf.setTimeZone(TimeZone.getTimeZone("Asia/Shanghai"));\n\n // Date 1: 1927-12-31 23:54:07\n Date date1 = sdf.parse("1927-12-31 23:54:07");\n // Date 2: 1927-12-31 23:54:08\n Date date2 = sdf.parse("1927-12-31 23:54:08");\n\n long diff = date2.get