Hibernate createQuery(".....")的几种不同用法

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String category = "abc";//顺便写

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//第一种:            Query query = em.createQuery("from Product as p where p.category = ?1");             query.setParameter(1, category);//第二种:            Query query = session.createQuery("from test.Product product whereproduct.category=?");            query.setString(0, category);//第三种:         Query query = em.createQuery("from Product as p wherep.category = :category");           query.setParameter("category", category);//第4种:         Query query = em.createQuery("select p  from Product p where p.id in (:ids)");           query.setParameter("ids", category);