Convert LocalDate to LocalDateTime or java.sql.Timestamp

Java Problem Overview

I am using JodaTime 1.6.2.

I have a LocalDate that I need to convert to either a (Joda) LocalDateTime, or a java.sqlTimestamp for ormapping.

The reason for this is I have figured out how to convert between a LocalDateTime and a java.sql.Timestamp:

LocalDateTime ldt = new LocalDateTime();
DateTimeFormatter dtf = DateTimeFormatter.forPattern("yyyy-MM-dd HH:mm:ss");
Timestamp ts = Timestamp.valueOf(ldt.toString(dtf));

So, if I can just convert between LocalDate and LocalDateTime, then I can make the continued conversion to java.sql.Timestamp. Thanks for any nudges in the right direction!

Java Solutions

Solution 1 - Java

JodaTime

To convert JodaTime's org.joda.time.LocalDate to java.sql.Timestamp, just do

Timestamp timestamp = new Timestamp(localDate.toDateTimeAtStartOfDay().getMillis());

To convert JodaTime's org.joda.time.LocalDateTime to java.sql.Timestamp, just do

Timestamp timestamp = new Timestamp(localDateTime.toDateTime().getMillis());

JavaTime

To convert Java8's java.time.LocalDate to java.sql.Timestamp, just do

Timestamp timestamp = Timestamp.valueOf(localDate.atStartOfDay());

To convert Java8's java.time.LocalDateTime to java.sql.Timestamp, just do

Timestamp timestamp = Timestamp.valueOf(localDateTime);

Solution 2 - Java

The best way use Java 8 time API:

  LocalDateTime ldt = timeStamp.toLocalDateTime();
  Timestamp ts = Timestamp.valueOf(ldt);

For use with JPA put in with your model (https://weblogs.java.net/blog/montanajava/archive/2014/06/17/using-java-8-datetime-classes-jpa):

@Converter(autoApply = true)
public class LocalDateTimeConverter implements AttributeConverter<LocalDateTime, Timestamp> {
    @Override
    public Timestamp convertToDatabaseColumn(LocalDateTime ldt) {
        return Timestamp.valueOf(ldt);
    }

    @Override
    public LocalDateTime convertToEntityAttribute(Timestamp ts) {
        return ts.toLocalDateTime();
    }
}

So now it is relative timezone independent time. Additionally it is easy do:

  LocalDate ld = ldt.toLocalDate();
  LocalTime lt = ldt.toLocalTime();

Formatting:

 DateTimeFormatter DATE_TME_FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm")
 String str = ldt.format(DATE_TME_FORMATTER);
 ldt = LocalDateTime.parse(str, DATE_TME_FORMATTER);

UPDATE: postgres 9.4.1208, HSQLDB 2.4.0 etc understand Java 8 Time API without any conversations!

Solution 3 - Java

tl;dr

The Joda-Time project is in maintenance-mode, now supplanted by java.time classes.

Just use java.time.Instant class.
No need for:
LocalDateTime
java.sql.Timestamp
Strings

Capture current moment in UTC.

Instant.now()

To store that moment in database:

myPreparedStatement.setObject( … , Instant.now() )  // Writes an `Instant` to database.

To retrieve that moment from datbase:

myResultSet.getObject( … , Instant.class )  // Instantiates a `Instant`

To adjust the wall-clock time to that of a particular time zone.

instant.atZone( z )  // Instantiates a `ZonedDateTime`

`LocalDateTime` is the wrong class

Other Answers are correct, but they fail to point out that LocalDateTime is the wrong class for your purpose.

In both java.time and Joda-Time, a LocalDateTime purposely lacks any concept of time zone or offset-from-UTC. As such, it does not represent a moment, and is not a point on the timeline. A LocalDateTime represents a rough idea about potential moments along a range of about 26-27 hours.

Use a LocalDateTime for either when the zone/offset is unknown (not a good situation), or when the zone-offset is indeterminate. For example, “Christmas starts at first moment of December 25, 2018” would be represented as a LocalDateTime.

Use a ZonedDateTime to represent a moment in a particular time zone. For example, Christmas starting in any particular zone such as Pacific/Auckland or America/Montreal would be represented with a ZonedDateTime object.

For a moment always in UTC, use Instant.

Instant instant = Instant.now() ;  // Capture the current moment in UTC.

Apply a time zone. Same moment, same point on the timeline, but viewed with a different wall-clock time.

ZoneId z = ZoneId.of( "Africa/Tunis" ) ;
ZonedDateTime zdt = instant.atZone( z ) ;  // Same moment, different wall-clock time.

>So, if I can just convert between LocalDate and LocalDateTime,

No, wrong strategy. If you have a date-only value, and you want a date-time value, you must specify a time-of-day. That time-of-day may not be valid on that date for a particular zone – in which case ZonedDateTime class automatically adjusts the time-of-day as needed.

LocalDate ld = LocalDate.of( 2018 , Month.JANUARY , 23 ) ;
LocalTime lt = LocalTime.of( 14 , 0 ) ;  // 14:00 = 2 PM.
ZonedDateTime zdt = ZonedDateTime.of( ld , lt , z ) ;

If you want the first moment of the day as your time-of-day, let java.time determine that moment. Do not assume the day starts at 00:00:00. Anomalies such as Daylight Saving Time (DST) mean the day may start at another time such as 01:00:00.

ZonedDateTime zdt = ld.atStartOfDay( z ) ;

`java.sql.Timestamp` is the wrong class

The java.sql.Timestamp is part of the troublesome old date-time classes that are now legacy, supplanted entirely by the java.time classes. That class was used to represent a moment in UTC with a resolution of nanoseconds. That purpose is now served with java.time.Instant.

JDBC 4.2 with `getObject`/`setObject`

As of JDBC 4.2 and later, your JDBC driver can directly exchange java.time objects with the database by calling:

For example:

myPreparedStatement.setObject( … , instant ) ;

… and …

Instant instant = myResultSet.getObject( … , Instant.class ) ;

Convert legacy ⬌ modern

If you must interface with old code not yet updated to java.time, convert back and forth using new methods added to the old classes.

Instant instant = myJavaSqlTimestamp.toInstant() ;  // Going from legacy class to modern class.

…and…

java.sql.Timestamp myJavaSqlTimestamp = java.sql.Timestamp.from( instant ) ;  // Going from modern class to legacy class.

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, 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.

Solution 4 - Java

function call asStartOfDay() on java.time.LocalDate object returns a java.time.LocalDateTime object

Solution 5 - Java

Depending on your timezone, you may lose a few minutes (1650-01-01 00:00:00 becomes 1649-12-31 23:52:58)

Use the following code to avoid that

new Timestamp(localDateTime.getYear() - 1900, localDateTime.getMonthOfYear() - 1, localDateTime.getDayOfMonth(), localDateTime.getHourOfDay(), localDateTime.getMinuteOfHour(), localDateTime.getSecondOfMinute(), fractional);

Solution 6 - Java

Since Joda is getting faded, someone might want to convert LocaltDate to LocalDateTime in Java 8. In Java 8 LocalDateTime it will give a way to create a LocalDateTime instance using a LocalDate and LocalTime. Check here.

>public static LocalDateTime of(LocalDate date, LocalTime time)

Sample would be,

    // just to create a sample LocalDate
	DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyyMMdd");
	LocalDate ld = LocalDate.parse("20180306", dtf);
	
	// convert ld into a LocalDateTime
	// We need to specify the LocalTime component here as well, it can be any accepted value
	LocalDateTime ldt = LocalDateTime.of(ld, LocalTime.of(0,0)); // 2018-03-06T00:00

Just for reference, For getting the epoch seconds below can be used,

    ZoneId zoneId = ZoneId.systemDefault();
	long epoch = ldt.atZone(zoneId).toEpochSecond(); 
	
	// If you only care about UTC
	long epochUTC = ldt.toEpochSecond(ZoneOffset.UTC);

Solution 7 - Java

Java8 +

import java.time.Instant;
Instant.now().getEpochSecond(); //timestamp in seconds format (int)
Instant.now().toEpochMilli(); // timestamp in milliseconds format (long)

Content Type	Original Author	Original Content on Stackoverflow
Question	IAmYourFaja	View Question on Stackoverflow
Solution 1 - Java	BalusC	View Answer on Stackoverflow
Solution 2 - Java	Grigory Kislin	View Answer on Stackoverflow
Solution 3 - Java	Basil Bourque	View Answer on Stackoverflow
Solution 4 - Java	Ahmad sibai	View Answer on Stackoverflow
Solution 5 - Java	user1302021	View Answer on Stackoverflow
Solution 6 - Java	prime	View Answer on Stackoverflow
Solution 7 - Java	Mohamed.Abdo	View Answer on Stackoverflow

Convert LocalDate to LocalDateTime or java.sql.Timestamp

Java Problem Overview

Java Solutions

Solution 1 - Java

JodaTime

JavaTime

Solution 2 - Java

Solution 3 - Java

tl;dr

`LocalDateTime` is the wrong class

`java.sql.Timestamp` is the wrong class

JDBC 4.2 with `getObject`/`setObject`

Convert legacy ⬌ modern

About java.time

Solution 4 - Java

Solution 5 - Java

Solution 6 - Java

Solution 7 - Java

How can I do time/hours arithmetic in Google Spreadsheet?

Convert a PHP script into a stand-alone windows executable

Attributions

Java Problem Overview

Java Solutions

Solution 1 - Java

JodaTime

JavaTime

Solution 2 - Java

Solution 3 - Java

tl;dr

LocalDateTime is the wrong class

java.sql.Timestamp is the wrong class

JDBC 4.2 with getObject/setObject

Convert legacy ⬌ modern

About java.time

Solution 4 - Java

Solution 5 - Java

Solution 6 - Java

Solution 7 - Java

How can I do time/hours arithmetic in Google Spreadsheet?

Convert a PHP script into a stand-alone windows executable

Attributions

`LocalDateTime` is the wrong class

`java.sql.Timestamp` is the wrong class

JDBC 4.2 with `getObject`/`setObject`