PageImpl在springboot中的JSON序列化问题

在rest api中使用 org.springframework.data.domain.PageImpl  返回分页数据，有出现一些问题，问题以及解决方式如下：

(1) 返回的结果在springboot 1.x 和 springboot 2.x中不一致

例如以下API

1@RestController
2public class SomeController {
3
4  @GetMapping
5  public PageImpl listAll() {
6    ...
7  }
8}

在springboot 1.x中的结果：

1{
2  "content": [
3    {...},
4    {...},
5    ....
6  ],
7  "totalElements": 50,
8  "totalPages": 3,
9  "last": false,
10  "size": 20,
11  "number": 0,
12  "numberOfElements": 1,
13  "first": true,
14  "sort": [
15    {
16      "direction": "DESC",
17      "property": "date",
18      "ignoreCase": false,
19      "nullHandling": "NATIVE",
20      "ascending": false,
21      "descending": true
22    }
23  ]
24}

然而在springboot 2.x中的结果除了content的内容相同，其他的内容都有很大的差别：

1{
2  "content": [
3    {...},
4    {...},
5    ....
6  ],
7  "pageable": {
8    "sort": {
9      "sorted": true,
10      "unsorted": false
11    },
12    "offset": 0,
13    "pageNumber": 0,
14    "pageSize": 20,
15    "paged": true,
16    "unpaged": false
17  },
18  "totalPages": 3,
19  "last": false,
20  "totalElements": 50,
21  "size": 20,
22  "number": 0,
23  "numberOfElements": 1,
24  "sort": {
25    "sorted": true,
26    "unsorted": false
27  },
28  "first": true
29}

怎么样才能在springboot2的结果和springboot1的一致呢？下面通过jackson自定义反序列实现

1import com.fasterxml.jackson.core.JsonGenerator;
2import com.fasterxml.jackson.databind.JsonSerializer;
3import com.fasterxml.jackson.databind.SerializerProvider;
4import org.springframework.boot.jackson.JsonComponent;
5import org.springframework.data.domain.PageImpl;
6import org.springframework.data.domain.Sort;
7
8import java.io.IOException;
9
10@JsonComponent
11public class PageImplJacksonSerializer extends JsonSerializer {
12    @Override
13    public void serialize(PageImpl page, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
14        jsonGenerator.writeStartObject();
15        jsonGenerator.writeObjectField("content", page.getContent());
16        jsonGenerator.writeBooleanField("first", page.isFirst());
17        jsonGenerator.writeBooleanField("last", page.isLast());
18        jsonGenerator.writeNumberField("totalPages", page.getTotalPages());
19        jsonGenerator.writeNumberField("totalElements", page.getTotalElements());
20        jsonGenerator.writeNumberField("numberOfElements", page.getNumberOfElements());
21        jsonGenerator.writeNumberField("size", page.getSize());
22        jsonGenerator.writeNumberField("number", page.getNumber());
23        Sort sort = page.getSort();
24        jsonGenerator.writeArrayFieldStart("sort");
25        for (Sort.Order order : sort) {
26            jsonGenerator.writeStartObject();
27            jsonGenerator.writeStringField("property", order.getProperty());
28            jsonGenerator.writeStringField("direction", order.getDirection().name());
29            jsonGenerator.writeBooleanField("ignoreCase", order.isIgnoreCase());
30            jsonGenerator.writeStringField("nullHandling", order.getNullHandling().name());
31            jsonGenerator.writeEndObject();
32        }
33        jsonGenerator.writeEndArray();
34        jsonGenerator.writeEndObject();
35    }
36}