使用Query和Aggregation仅获取嵌入式文档不能很好地工作

Question

我的收藏中有多个地址，我想要获取所有这些地址，我该怎么做？我在下面试过，但效果不好。

Query query = new Query();
query.fields().include("Address");
List<Address> list1 = template.find(query, Address.class);
System.out.println(list1);

这是集合

{
  "_id" : ObjectId("592c7029aafef820f432c5f3"),
  "_class" : "lankydan.tutorial.mongodb.documents.Person",
  "firstName" : "John",
  "secondName" : "Doe",
  "dateOfBirth" : ISODate("2017-05-29T20:02:01.636+01:00"),
  "address" : [
      {
        "addressLineOne" : "19 Imaginary Road",
        "addressLineTwo" : "Imaginary Place",
        "city" : "Imaginary City",
        "country" : "US"
      },
      {
        "addressLineOne" : "22 South Road",
        "addressLineTwo" : "South Place",
        "city" : "CA",
        "country" : "US"
      }
    ],
  "profession" : "Winner",
  "salary" : 100,
  "hobbies" : [ 
    {
      "name" : "Badminton"
    }, 
    {
      "name" : "TV"
    }
  ]
} 

下面的效果很好，但我放弃了User集合的findAll（）方法。如何填补这个空白？

@Query(value = "{}", fields = "{_id : 0, address:1}")
List<User> findAll();

Answer 1

你需要通过在_id中添加qazxsw poi运算符来删除qazxsw poi中的qazxsw poi，如下所示：

query fields

希望这能解决你的问题。