1. Java Date Time Tutorial
2. Java System.currentTimeMillis()
3. Java Time Measurement
4. Java's java.util.Date
5. Java's java.sql.Date
6. Java's java.sql.Timestamp
7. Java's java.util.Calendar and GregorianCalendar
8. Java's java.util.TimeZone
9. Parsing and Formatting Dates in Java
10. Java Instant
11. Java Duration
12. Java LocalDate
13. Java LocalTime
14. Java LocalDateTime
15. Java ZonedDateTime
16. Java DateTimeFormatter

Java's java.sql.Timestamp class is used in the JDBC API. If you need to set a date + time on a java.sql.PreparedStatement or get a date + time from a java.sql.ResultSet, you will interact with java.sql.Timestamp.

Actually, java.sql.Timestamp extends java.util.Date, so anything you can do with a java.util.Date you can also do with a java.sql.Timestamp. Check out java.util.Date for more details.

The biggest difference between java.sql.Date and java.sql.Timestamp is that the java.sql.Date only keeps the date, not the time, of the date it represents. So, for instance, if you create a java.sql.Date using the date and time 2009-12-24 23:20, then the time (23:20) would be cut off. If you use a java.sql.Timestamp then the time is kept.

Nanoseconds

One difference in the java.sql.Timestamp from its superclass java.util.Date is its ability to hold the nanoseconds of a date too. You can get and set the nanoseconds using the getNanos() and setNanos(). Here is how:

long time = System.currentTimeMillis();
java.sql.Timestamp timestamp = new java.sql.Timestamp(time);

timestamp.setNanos(123456);
int nanos = timestamp.getNanos(); // nanos = 123456