[英]How to write this query using JPA Criteria query?
任何人都可以幫助我獲得下面提到的JPA查詢的JPA條件查詢。
SELECT p,l FROM Person p
LEFT JOIN Language l ON (p.language = l.language and l.locale like :locale)
AND p.name like :name
AND p.time BETWEEN :startDate
AND :endDate order by name asc
假設Person與語言有關系,那么你將在舊的Hibernate中做些什么:
Criteria criteria = entityManager.createCriteria(Person.class);
Criteria languageCriteria = criteria.createCriteria("language");
languageCriteria.add(Restrictions.like("locale", locale));
criteria.add(Restrictions.like("name", name));
criteria.add(Restrictions.between("time", startDate, endDate));
criteria.addOrder(Order.asc("name"));
我第一次嘗試JPA 2.0:
CriteriaBuilder builder = entityManager.getCriteriaBuilder();
CriteriaQuery<Person> criteria = builder.createCriteria(Person.class);
Root<Person> pRoot = criteria.from(Person.class);
Join<Person, Language> langJoin = criteria.join("language", JoinType.LEFT);
Predicate conjunction = builder.conjunction();
criteria.where(builder.and(
builder.like(langJoin.get(Language_.locale), locale),
builder.like(pRoot.get(Person_.name), name),
builder.between(pRoot.get(Person_.time), startDate, endDate));
criteria.orderBy(builder.asc(pRoot.get(Person_.name)));
如果這對您有用,請告訴我。
編輯:更新的查詢只使用一個where
通話。
雖然johncarl給出的答案被接受,但對我來說看起來並不正確。 CriteriaQuery.where()的JavaDocs說:
修改查詢以根據指定的布爾表達式限制查詢結果。 替換之前添加的限制(如果有)。
據我了解,以下每一行(給出限制)都將覆蓋先前給出的限制:
criteria.where(builder.like(langJoin.get(Language_.locale), locale));
criteria.where(builder.like(pRoot.get(Person_.name), name));
criteria.where(builder.between(pRoot.get(Person_.time), startDate, endDate));
這意味着最終只剩下最后一個限制(開始和結束日期之間)。
我建議對johncarl的答案進行以下修改:
CriteriaBuilder builder = entityManager.getCriteriaBuilder();
CriteriaQuery<Person> criteria = builder.createCriteria(Person.class);
Root<Person> pRoot = criteria.from(Person.class);
Join<Person, Language> langJoin = criteria.join("language", JoinType.LEFT);
Predicate[] restrictions = new Predicate[] {
builder.like(langJoin.get(Language_.locale), locale),
builder.like(pRoot.get(Person_.name), name),
builder.between(pRoot.get(Person_.time), startDate, endDate)
};
criteria.where(builder.and(restrictions));
criteria.orderBy(builder.asc(pRoot.get(Person_.name)));
但是,這段代碼看起來真的很難看! 如果您錯了,請隨時編輯,如果您看到更好的解決方案,請發表評論! 我會優雅的!
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