如果我使用连接在条件查询中创建谓词,我将不会得到任何结果。当我将 Game
表用作根时,相同的谓词返回实体。
工作查询:
CriteriaQuery<Game> query = cb.createQuery(Game.class);
Root<Game> root = query.from(Game.class);
List<Predicate> predicates = new LinkedList<Predicate>();
if(!selectedPlatforms.isEmpty()) {
predicates.add(root.get(Game_.type).in(TypeConverter.convert(selectedPlatforms)));
}
if(!selectedCategories.isEmpty()) {
Join<Game, String> collection = root.join(Game_.categories);
predicates.add(collection.in(cb.literal(selectedCategories)));
}
if(!selectedGames.isEmpty()) {
predicates.add(cb.isTrue(root.get(Game_.name).in(selectedGames)));
}
query.where(cb.and(predicates.toArray(new Predicate[predicates.size()])));
games = em.createQuery(query).getResultList();
无效查询:
CriteriaQuery<Hit> query = cb.createQuery(Hit.class);
List<Predicate> predicates = new LinkedList<>();
Date startDate = null;
Date endDate = null;
Root<Hit> hitRoot = query.from(Hit.class);
switch (time) {
case "Week":
startDate = new DateTime().withWeekOfWeekyear(timeValue).withDayOfWeek(DateTimeConstants.MONDAY).toDate();
endDate = new DateTime().withWeekOfWeekyear(timeValue+1).withDayOfWeek(DateTimeConstants.SUNDAY).toDate();
}
predicates.add(cb.and(cb.greaterThanOrEqualTo(hitRoot.<Date>get("hitDate"), startDate), cb.lessThanOrEqualTo(hitRoot.<Date>get("hitDate"), endDate)));
Join<Hit, Game> gameJoin = hitRoot.join("game", JoinType.LEFT);
if(!selectedPlatforms.isEmpty()) {
predicates.add(gameJoin.get(Game_.type).in(TypeConverter.convert(selectedPlatforms)));
}
if(!selectedCategories.isEmpty()) {
Join<Game, String> collection = gameJoin.join(Game_.categories);
predicates.add(collection.in(cb.literal(selectedCategories)));
}
if(!selectedGames.isEmpty()) {
predicates.add(cb.isTrue(gameJoin.get(Game_.name).in(selectedGames)));
}
query.groupBy(hitRoot.get("hitDate"), hitRoot.get("shop"));
query.orderBy(cb.asc(hitRoot.get("shop")));
query.where(predicates.toArray(new Predicate[predicates.size()]));
List<Hit> results = em.createQuery(query).getResultList();
以下部分负责不返回任何匹配实体。相同的部分只是应用于 Root
而不是 Join
,就像在第一个查询中一样返回 machting entites。没有这部分,其他一切都在工作。
if(!selectedGames.isEmpty()) {
predicates.add(cb.isTrue(gameJoin.get(Game_.name).in(selectedGames)));
}
最佳答案
问题通过在“运行”模式下重新启动应用程序服务器自行解决。
关于java - Join 上的谓词不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19192183/