比较Hibernate中datetime字段的时间部分

<class>com.example.entity.YourEntity</class>
<properties>
  <property name="yourDateTimeColumnName">
       type="timestamp"
       access="property" />
   </property>
 </properties>

Session session = ...; // 打开Hibernate Session
Expression<Date> birthDateExpression = session
    .getSessionFactory()
    .getCurrentSession()
    .getCriteriaBuilder()
    .getDate(YourEntity.YourDateTimeField.yourDateTimeColumnName)
    .greaterThanOrEqualTo(new Date())
    .andLessThan(new Date(System.currentTimeMillis() + 1000))
    .toExpression();
List<YourEntity> birthDateResults = session
    .createCriteria(YourEntity.class)
    .add(birthDateExpression)
    .list();

Date newDate = ...; // 从查询获取或自己填充的新日期时间

CriteriaBuilder criteriaBuilder = session.getSessionFactory().getCurrentSession()
    .getCriteriaBuilder();

Criteria updateCriteria = criteriaBuilder.createCriteria(
        YourEntity.class)
    .setProperty(YourEntity.YourDateTimeField.yourDateTimeColumnName)
    .setParameter(yourDateTimeColumnName, newDate);

List<YourEntity> updatedEntities = updateCriteria.list();
session.update(updatedEntities);
session.flush();