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Criteria query for a many to one relationship with join fetch 

CriteriaBuilder cb = _entityManager.getCriteriaBuilder();
CriteriaQuery<Message> criteriaQuery = cb.createQuery(Message.class);
Root<Message> messageRoot = criteriaQuery.from(Message.class);
Root<Device> deviceRoot = criteriaQuery.from(Device.class);

Fetch<Message, Device> recipientDeviceFetch = messageRoot.fetch("recipientDevice", JoinType.LEFT);
Join<Message, Device> messageRecipientDeviceJoin = (Join<Message, Device>) recipientDeviceFetch;

criteriaQuery.where(cb.and(messageRoot.get(Message.COLUMN_ID).in(messageIdsToDelete),
        cb.equal(deviceRoot.get(Device.COLUMN_PRIMARY_KEY), devicePrimaryKey)));
criteriaQuery.select(cb.construct(Message.class, messageRoot.get("recipientDevice"), messageRoot.get(Message.COLUMN_CLIENT_MESSAGE_ID)));

List<Message> messages = _entityManager.createQuery(criteriaQuery).getResultList();

return messages;

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