suppose I have an entity class Article
@Data
@Document(collection = "articles")
public final class Article {
@Id
private String id;
private String name;
private String url;
private String author;
private List<Comment> comments;
}entity class Comment
@Data
public final class Comment {
private String userId;
private String content;
} has added several pieces of data through the test case. Assume that the _ id of one of the Article is 5b5694f38ec9b636c4e52d69 , and the
can obtain the Article, of this id through MongoRepository , or through MongoTemplate ,
final String id = "5b5694f38ec9b636c4e52d69";
Query query = new Query()
.addCriteria(Criteria.where("id").is(id));
Article article = mongoTemplate.findOne(query, Article.class);so you can get it. Now I just want to get the List < Comment >,
of this Article.Document queryObject = new Document();
queryObject.put("id", id);
Document fieldsObject = new Document();
fieldsObject.put("id", false);
fieldsObject.put("comments", true);
Query query = new BasicQuery(queryObject, fieldsObject);if I return List when I find
List comments = mongoTemplate.findOne(query, List.class);there is no doubt that an exception will occur. Return Article
Article article = mongoTemplate.findOne(query, Article.class);
List<Comment> comments = Optional.of(article).orElseThrow(ArticleNotFoundException::new)
.getComments(); this allows you to get List < Comment > , but it doesn"t make much sense to get a specified number of Commit (subList ().
is there any way to return List < Commit > directly so that you can use limit () and skip () ; if not, is there a way to achieve the same effect as limit () skip () ?