如何在 sping Data JPA 中使用 CriteriaUpdate 执行更新操作？

Question

As spring data JPA provide specification to get result like below

public static Specification<Customer> customerHasBirthday() {
    return new Specification<Customer> {
        public Predicate toPredicate(Root<T> root, CriteriaQuery query, CriteriaBuilder cb) {
            return cb.equal(root.get(Customer_.birthday), today);
        }
    };
}

and then we can pass above specification in repository method customerRepository.findAll(customerHasBirthday); Now I want to perform update operation using criteria update in spring data JPA like below

public static Specification<Customer> upadteCustomerName() {
    return new Specification<Customer> {
        public Predicate toPredicate(Root<Customer> root, CriteriaQuery query, CriteriaBuilder cb) {
            CriteriaUpdate<Customer> update = cb.createCriteriaUpdate(Customer.class)
            update.set("name", "newName");
            return update.where(cb.greaterThanOrEqualTo(root.get("id"), 2));
        }
    };
}

Obviously I will get compile time error as

CriteriaUpdate can not be converted into predicate

Is spring data JPA provide any easy way to implement CriteriaUpdate and then directly pass the instance to Repository method like in Get operation we have findAll() method?

or is there any other best way to implement criteriaUpdate in spring Data JPA?

Answer 1

Based on this answer you can do like this:

CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaUpdate<Customer> q = cb.createCriteriaUpdate(Customer.class);
Root<Customer> root = q.from(Customer.class);
q.set(root.get("name"),  "newName")
        .where(cb.greaterThanOrEqualTo(root.get("id"), 2)); 

int result = em.createQuery(q).executeUpdate();