How to convert java.util.Date to java.sql.Date?

Question

I am trying to use a java.util.Date as input and then creating a query with it - so I need a java.sql.Date.

I was surprised to find that it couldn't do the conversion implicitly or explicitly - but I don't even know how I would do this, as the Java API is still fairly new to me.

Answer 1

tl;dr

How to convert java.util.Date to java.sql.Date?

Don’t. Both classes are outmoded.

• Use java.time classes instead of legacy java.util.Date & java.sql.Date with JDBC 4.2 or later.
• Convert to/from java.time if inter-operating with code not yet updated to java.time.

Example query with PreparedStatement.

myPreparedStatement.setObject( 
    … ,                                         // Specify the ordinal number of which argument in SQL statement.
    myJavaUtilDate.toInstant()                  // Convert from legacy class `java.util.Date` (a moment in UTC) to a modern `java.time.Instant` (a moment in UTC).
        .atZone( ZoneId.of( "Africa/Tunis" ) )  // Adjust from UTC to a particular time zone, to determine a date. Instantiating a `ZonedDateTime`.
        .toLocalDate()                          // Extract a date-only `java.time.LocalDate` object from the date-time `ZonedDateTime` object.
)

Replacements:

• Instant instead of java.util.Date
  Both represent a moment in UTC. but now with nanoseconds instead of milliseconds.
• LocalDate instead of java.sql.Date
  Both represent a date-only value without a time of day and without a time zone.

Details

If you are trying to work with date-only values (no time-of-day, no time zone), use the LocalDate class rather than java.util.Date.

java.time

In Java 8 and later, the troublesome old date-time classes bundled with early versions of Java have been supplanted by the new java.time package. See Oracle Tutorial. Much of the functionality has been back-ported to Java 6 & 7 in ThreeTen-Backport and further adapted to Android in ThreeTenABP.

A SQL data type DATE is meant to be date-only, with no time-of-day and no time zone. Java never had precisely such a class† until java.time.LocalDate in Java 8. Let's create such a value by getting today's date according to a particular time zone (time zone is important in determining a date as a new day dawns earlier in Paris than in Montréal, for example).

LocalDate todayLocalDate = LocalDate.now( ZoneId.of( "America/Montreal" ) );  // Use proper "continent/region" time zone names; never use 3-4 letter codes like "EST" or "IST".

At this point, we may be done. If your JDBC driver complies with JDBC 4.2 spec, you should be able to pass a LocalDate via setObject on a PreparedStatement to store into a SQL DATE field.

myPreparedStatement.setObject( 1 , localDate );

Likewise, use ResultSet::getObject to fetch from a SQL DATE column to a Java LocalDate object. Specifying the class in the second argument makes your code type-safe.

LocalDate localDate = ResultSet.getObject( 1 , LocalDate.class );

In other words, this entire Question is irrelevant under JDBC 4.2 or later.

If your JDBC driver does not perform in this manner, you need to fall back to converting to the java.sql types.

Convert to java.sql.Date

To convert, use new methods added to the old date-time classes. We can call java.sql.Date.valueOf(…) to convert a LocalDate.

java.sql.Date sqlDate = java.sql.Date.valueOf( todayLocalDate );

And going the other direction.

LocalDate localDate = sqlDate.toLocalDate();

Converting from java.util.Date

While you should avoid using the old date-time classes, you may be forced to when working with existing code. If so, you can convert to/from java.time.

Go through the Instant class, which represents a moment on the timeline in UTC. An Instant is similar in idea to a java.util.Date. But note that Instant has a resolution up to nanoseconds while java.util.Date has only milliseconds resolution.

To convert, use new methods added to the old classes. For example, java.util.Date.from( Instant ) and java.util.Date::toInstant.

Instant instant = myUtilDate.toInstant();

To determine a date, we need the context of a time zone. For any given moment, the date varies around the globe by time zone. Apply a ZoneId to get a ZonedDateTime.

ZoneId zoneId = ZoneId.of ( "America/Montreal" );
ZonedDateTime zdt = ZonedDateTime.ofInstant ( instant , zoneId );
LocalDate localDate = zdt.toLocalDate();

---

† The java.sql.Date class pretends to be date-only without a time-of-day but actually does a time-of-day, adjusted to a midnight time. Confusing? Yes, the old date-time classes are a mess.

---

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.

Where to obtain the java.time classes?

• Java SE 8, Java SE 9, Java SE 10, and later
  • Built-in.
  • Part of the standard Java API with a bundled implementation.
  • Java 9 adds some minor features and fixes.
• Java SE 6 and Java SE 7
  • Much of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
• Android
  • Later versions of Android bundle implementations of the java.time classes.
  • For earlier Android (<26), the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

Answer 2

In my case of picking date from JXDatePicker (java calender) and getting it stored in database as SQL Date type, below works fine ..

java.sql.Date date = new java.sql.Date(pickedDate.getDate().getTime());

where pickedDate is object of JXDatePicker

Answer 3

I am a novice: after much running around this worked. Thought might be useful

     String bufDt =  bDOB.getText();  //data from form
     DateFormat dF = new SimpleDateFormat("dd-MM-yyyy"); //data in form is in this format
     Date bbdt = (Date)dF.parse(bufDt);  // string data is converted into java util date
     DateFormat dsF = new SimpleDateFormat("yyyy-MM-dd"); //converted date is reformatted for conversion to sql.date
     String ndt = dsF.format(bbdt); // java util date is converted to compatible java sql date
     java.sql.Date sqlDate=  java.sql.Date.valueOf(ndt);  // finally data from the form is convered to java sql. date for placing in database

Answer 4

Method for comparing 2 dates (util.date or sql.date)

 public static boolean isSameDay(Date a, Date b) {
    Calendar calA = new GregorianCalendar();
    calA.setTime(a);

    Calendar calB = new GregorianCalendar();
    calB.setTime(b);

    final int yearA = calA.get(Calendar.YEAR);
    final int monthA = calA.get(Calendar.MONTH);
    final int dayA = calA.get(Calendar.DAY_OF_YEAR);

    final int yearB = calB.get(Calendar.YEAR);
    final int monthB = calB.get(Calendar.MONTH);
    final int dayB = calB.get(Calendar.DAY_OF_YEAR);

    return yearA == yearB && monthA == monthB && dayA == dayB;
}

Answer 5

Here the example of converting Util Date to Sql date and ya this is one example what i am using in my project might be helpful to you too.

java.util.Date utilStartDate = table_Login.getDob();(orwhat ever date your give form obj)
java.sql.Date sqlStartDate = new java.sql.Date(utilStartDate.getTime());(converting date)