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Convert java.time.LocalDate into java.util.Date type

java
date-conversion
time-zone
java-time-api
Anton ShumikhinbyAnton Shumikhin·Jan 6, 2025
TLDR

To convert LocalDate to util.Date, you can utilize java.sql.Date.valueOf:

LocalDate localDate = LocalDate.now(); java.util.Date date = java.sql.Date.valueOf(localDate);

This method maps the LocalDate to its SQL variant, which is a subclass of java.util.Date. However, consider that this method uses implicit time zone that could be different from your system's default.

Accurate conversion with time zone considerations

Time zone transformation

For precise control over time zones, transform LocalDate to ZonedDateTime:

LocalDate localDate = LocalDate.now(); // Hold my toast! I'm going back in time with my own timezone. ZonedDateTime zdt = localDate.atStartOfDay(ZoneId.systemDefault()); Date date = Date.from(zdt.toInstant());

This approach allows you to convert accurately, considering time zone in the process.

Precise milliseconds conversion

When dealing with Instant, representing epoch-millisecond, ensure to multiply seconds by 1000 for conversion:

LocalDate localDate = LocalDate.now(); Instant instant = localDate.atStartOfDay(ZoneId.systemDefault()).toInstant(); // Instant! No, not coffee. A point in time! Date date = new Date(instant.toEpochMilli());

Exploring libraries and tools

Integrating with UI

If you are working with UI components like JDateChooser, a utility method like DateUtils.asDate(LocalDate) provides easier integration.

Libraries with java.time support

Third-party libraries like JDatePicker directly handle LocalDate, offering better compatibility and efficiency.

Utilize date libraries

Libraries like Joda-Time and Apache Commons Lang have utility classes to simplify date conversions.

Time zone handling

Specify time zones explicitly while dealing with java.util.Date and java.time to avoid ambiguity.

Daylight Saving Time

Daylight Saving Time might cause resolution conflicts. LocalDate lacks time information that might become relevant during DST switch.

Transitioning to java.time API

Embrace newer APIs

Using java.time API completely can eliminate the need for these conversions, being a modern and capable standard from Java 8 onwards.

Libraries' compatibility

Before choosing any date-time solution, ensure its compatibility with java.time API to sidestep unnecessary complications.