The Value of Annotation @Temporal for Date Related Columns

The annotation @Temporal in official javadoc is described like below:

This annotation must be specified for persistent fields or properties of type java.util.Date and java.util.Calendar.

So when the field variable is a java.util.Date or java.util.Calendar, it MUST be annotated by @Temporal.

There are 3 values for @Temporal

• TemporalType.DATE
• TemporalType.TIME
• TemporalType.TIMESTAMP

Here is a demo to show the usage of there 3 values. The Entity 'MyEntity' has a field called 'lastUpdateTime' which is a defined as a java.util.Date variable. let's update it in java like this:

1 2 3 4 5

import java.util.Date; //... // MyEntity is the JPA entity, em is EntityManager context MyEntity e = em.find(MyEntity.class, 1L); //get the row with id=1 e.setLastUpdateTime(new Date());

TemporalType.DATE

If the column annotated with @Temporal(TemporalType.DATE) like this:

1 2 3

@Temporal(TemporalType.DATE) @Column(name="LAST_UPDATE_TIME") private Date lastUpdateTime;

The record in database after update will look like:

TemporalType.TIME

If the column annotatedwith @Temporal(TemporalType.TIME) like this:

1 2 3

@Temporal(TemporalType.TIME) @Column(name="LAST_UPDATE_TIME") private Date lastUpdateTime;

The record in database after update will look like:

TemporalType.TIMESTAMP

If the column annotated with @Temporal(TemporalType.TIMESTAMP) like this:

1 2 3

@Temporal(TemporalType.TIMESTAMP) @Column(name="LAST_UPDATE_TIME") private Date lastUpdateTime;

The record in database after update will look like: