without increment mvc spring

1import org.springframework.beans.factory.annotation.Autowired;
2import org.springframework.data.mongodb.core.FindAndModifyOptions;
3import org.springframework.data.mongodb.core.MongoTemplate;
4import org.springframework.data.mongodb.core.query.Criteria;
5import org.springframework.data.mongodb.core.query.Query;
6import org.springframework.data.mongodb.core.query.Update;
7import org.springframework.stereotype.Service;
8import sample.data.mongo.models.IdGenerator;
9import sample.data.mongo.repository.IdGeneratorRepository;
10
11@Service
12public class IdGeneratorService {
13
14  @Autowired
15  private IdGeneratorRepository idGeneratorRepository;
16
17  @Autowired
18  private MongoTemplate mongoTemplate;
19
20  public long generateId(String key) {
21
22    Query query = new Query();
23    // key = identified_by_Id;
24    Criteria criteria = new Criteria("identifier").is(key);
25    query.addCriteria(criteria);
26
27    Update update = new Update();
28    update.inc("counter", 1);
29
30    FindAndModifyOptions options = new FindAndModifyOptions();
31    options.upsert(true);
32    options.returnNew(true);
33
34    IdGenerator idGenerator = mongoTemplate
35        .findAndModify(query, update, options, IdGenerator.class);
36
37    return idGenerator.getCounter();
38  }
39}