Hibernate Criteria从日期开始提取年份

Question

我创建了一个休眠标准,用于检查合同是否在一年内有效.合同的开始日期和结束日期作为标准日期字段.

所以习惯SQL-SERVER,我会想到这个SQL的内容:

SELECT * FROM CONTRACT WHERE YEAR(startDate) <= ? AND YEAR(endDate) >= ?

该问号是给定年份的整数.

那么如何将其转换为休眠标准呢？

int year = 2011; //Just a testyear for example purposes.
DetachedCriteria criteria = DetachedCriteria.forClass(Contract.class)
    .add(Restrictions.le("startDate", year))
    .add(Restrictions.ge("endDate", year));

正如你所看到的,我错过了将日期转换为一年的位置,因此可以进行比较.当然,我的代码不会按原样运行.

有关如何获得理想结果的任何建议？

Answer 1

看起来API并不直接支持您想要的内容,但您可以考虑使用解决方法.

解决方案1:

DetachedCriteria criteria = DetachedCriteria.forClass(Contract.class)
    .add(Restrictions.le("startDate", toEndOfYear(year))
    .add(Restrictions.ge("endDate", toStartOfYear(year)));

public Date toStartOfYear(int year) {
    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.YEAR, year);
    calendar.set(Calendar.DAY_OF_YEAR, 0);
    calendar.set(Calendar.HOUR_OF_DAY, 0);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND, 0);
    return calendar.getTime();
}

public Date toEndOfYear(int year) {
    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.YEAR, year);
    calendar.set(Calendar.DAY_OF_YEAR, 0);
    calendar.set(Calendar.HOUR_OF_DAY, 0);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND,-1);
    return calendar.getTime();
}

两种方法的输出示例:

System.out.println(toStartOfYear(2013));
System.out.println(toEndOfYear(2013));

Mon Dec 31 00:00:00 MYT 2012
Sun Dec 30 23:59:59 MYT 2012

解决方案2:

DetachedCriteria criteria = DetachedCriteria.forClass(Contract.class)
    .add(Restrictions.sqlRestriction("YEAR(startDate) >= ? ", year,Hibernate.INTEGER))
    .add(Restrictions.sqlRestriction("YEAR(endDate) <= ? ", year,Hibernate.INTEGER));

Answer 2

使用Restrictions.sqlRestriction它将解决您的问题

Answer 3

如果您使用JPA criteriaBuilder,则可以使用该criteriaBuilder.function方法.例如

contractRepository.findAll(new Specification<Contract>() {
   @Override
   public Predicate toPredicate(Root<Contract> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
     return cb.ge(cb.function("year", Integer.class, root.get(Contract_.endDate)), year);
   }
});

(我在本例中使用Spring Data Specifications来查询数据库.contractRepository因此是类型JpaSpecificationExecutor)