如何将Spring Pageable响应中的content字段修改为data？

我的控制器代码如下：

@GetMapping("/report-authors")
@ResponseBody 
public Page<MyObject> getSth(){ ... }

当前返回的JSON结构为：

{
  "content": [
      <MyObject>
  ],
  "pageable": {
      ...
  },
  "last": false,
  "total_pages": 163,
  "total_elements": 3246,
  "size": 20,
  "number": 0,
  "sort": {
      "empty": false,
      "sorted": true,
      "unsorted": false
  },
  "number_of_elements": 20,
  "first": true,
  "empty": false
}

需要将响应中的content字段名称修改为data，期望得到的JSON结构如下：

{
  "data": [
      <MyObject>
  ],
  "pageable": {
           ...     
  },
  "last": false,
  "total_pages": 163,
  "total_elements": 3246,
  "size": 20,
  "number": 0,
  "sort": {
      "empty": false,
      "sorted": true,
      "unsorted": false
  },
  "number_of_elements": 20,
  "first": true,
  "empty": false
}

下面提供三种可行的实现方式，根据你的场景选择即可：

方式一：使用Jackson Mixin扩展Page类（推荐） #

无需修改原有业务代码，通过Jackson的Mixin机制重写content字段的序列化名称：

1. 创建Page的Mixin抽象类：

import com.fasterxml.jackson.annotation.JsonProperty;
import org.springframework.data.domain.Page;
import java.util.List;

public abstract class PageMixin<T> {
    @JsonProperty("data")
    abstract List<T> getContent();

    // 保留其他分页字段的原有序列化名称
    @JsonProperty("total_pages")
    abstract int getTotalPages();

    @JsonProperty("total_elements")
    abstract long getTotalElements();

    @JsonProperty("number_of_elements")
    abstract int getNumberOfElements();
}

2. 在Jackson配置类中注册Mixin：

import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.domain.Page;

@Configuration
public class JacksonConfig {
    @Bean
    public ObjectMapper objectMapper() {
        ObjectMapper mapper = new ObjectMapper();
        mapper.addMixIn(Page.class, PageMixin.class);
        return mapper;
    }
}

方式二：自定义分页DTO包装结果 #

通过创建自定义分页DTO类，将Spring Data的Page对象转换为DTO后返回：

1. 定义分页DTO类：

import lombok.Data;
import org.springframework.data.domain.Page;
import java.util.List;

@Data
public class PageDTO<T> {
    private List<T> data;
    private Object pageable;
    private boolean last;
    private int total_pages;
    private long total_elements;
    private int size;
    private int number;
    private Object sort;
    private int number_of_elements;
    private boolean first;
    private boolean empty;

    // 静态方法实现Page到DTO的转换
    public static <T> PageDTO<T> fromPage(Page<T> page) {
        PageDTO<T> dto = new PageDTO<>();
        dto.setData(page.getContent());
        dto.setPageable(page.getPageable());
        dto.setLast(page.isLast());
        dto.setTotal_pages(page.getTotalPages());
        dto.setTotal_elements(page.getTotalElements());
        dto.setSize(page.getSize());
        dto.setNumber(page.getNumber());
        dto.setSort(page.getSort());
        dto.setNumber_of_elements(page.getNumberOfElements());
        dto.setFirst(page.isFirst());
        dto.setEmpty(page.isEmpty());
        return dto;
    }
}

2. 修改控制器方法的返回值：

@GetMapping("/report-authors")
@ResponseBody 
public PageDTO<MyObject> getSth(){ 
    Page<MyObject> pageResult = ...; // 原有分页查询逻辑
    return PageDTO.fromPage(pageResult);
}

方式三：自定义Jackson序列化器 #

编写自定义序列化器，手动控制Page对象的JSON输出格式：

1. 实现自定义序列化器：

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import org.springframework.data.domain.Page;
import java.io.IOException;

public class CustomPageSerializer extends JsonSerializer<Page<?>> {
    @Override
    public void serialize(Page<?> page, JsonGenerator gen, SerializerProvider serializers) throws IOException {
        gen.writeStartObject();
        // 将content替换为data
        gen.writeObjectField("data", page.getContent());
        // 写入其他分页字段
        gen.writeObjectField("pageable", page.getPageable());
        gen.writeBooleanField("last", page.isLast());
        gen.writeNumberField("total_pages", page.getTotalPages());
        gen.writeNumberField("total_elements", page.getTotalElements());
        gen.writeNumberField("size", page.getSize());
        gen.writeNumberField("number", page.getNumber());
        gen.writeObjectField("sort", page.getSort());
        gen.writeNumberField("number_of_elements", page.getNumberOfElements());
        gen.writeBooleanField("first", page.isFirst());
        gen.writeBooleanField("empty", page.isEmpty());
        gen.writeEndObject();
    }
}

2. 注册序列化器到Jackson配置：

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.domain.Page;

@Configuration
public class JacksonConfig {
    @Bean
    public ObjectMapper objectMapper() {
        ObjectMapper mapper = new ObjectMapper();
        SimpleModule module = new SimpleModule();
        module.addSerializer(Page.class, new CustomPageSerializer());
        mapper.registerModule(module);
        return mapper;
    }
}

内容的提问来源于stack exchange，提问作者Maxwell Cheng