如何使用聚合类将现有的mongo db查询转换为spring boot

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

spring.data.mongodb.uri=mongodb://localhost:27017/mydatabase

@Document(collection = "users")
public class User {
    @Id
    private String id;
    private String name;
    private int age;
    // getters and setters
}

@Autowired
private MongoTemplate mongoTemplate;

public List<User> aggregateQuery() {
    Aggregation aggregation = Aggregation.newAggregation(
        Aggregation.match(Criteria.where("age").gt(18)),
        Aggregation.group("name").count().as("count"),
        Aggregation.sort(Sort.Direction.DESC, "count")
    );
    AggregationResults<User> results = mongoTemplate.aggregate(aggregation, "users", User.class);
    return results.getMappedResults();
}

List<User> users = aggregateQuery();