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.Date class is used in the JDBC API. If you need to set a date on a java.sql.PreparedStatement or get a date from a java.sql.ResultSet, you will interact with java.sql.Date.

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

Here is how to instantiate a java.sql.Date

long time = System.currentTimeMillis();
java.sql.Date date = new java.sql.Date(time);

The biggest difference between java.sql.Date and java.util.Date 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 need to keep the time, use a java.sql.Timestamp instead.