@JsonSerialize注解的使用示例教程

package org.demo.common.json;
import com.alibaba.fastjson.JSONObject;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import java.io.IOException;
import java.util.List;
/**
 *
 * @Description: 序列化工具,将list集合转字符串
 * @Author: xqf
 * @Date: 2023-11-25
 * @Version: V1.0
 * /
  /**继承JsonSerializer*/
public class ToArraysSerializer extends JsonSerializer<String> {
    /**
     * 重写serialize方法
     **/
    @Override
    public void serialize(String object, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException, JsonProcessingException {
        /**自定义处理方式*/
        List<String> list = JSONObject.parseObject(object, List.class);
        jsonGenerator.writeObject(list);
    }
}

    /**
     * 文章内容
     */
    @ApiModelProperty(value = "文章内容")
    @JsonSerialize(using = ToArraysSerializer.class)
    private String content;

    /**
     * 文章内容
     */
    @ApiModelProperty(value = "文章内容")
    @JsonSerialize(nullsUsing = xxx.class)
    private String content;

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  <version>2.13.3</version>
</dependency>

@JsonSerialize(include = JsonSerialize.Inclusion.NON_NULL) //include里面包含了序列化的范围和作用的规则，本行作用是属性为null的时候不进行序列化操作。
@JsonSerialize(using = ToStringSerializer.class) //将id实现字符串的序列化和反序列序列化
@JsonSerialize(nullsUsing = DateJsonSerialize.class) //当此字段为NULL时就使用我们自定义的解析类序列化此字段(注意当此字段不为NULL时不执行此配置)
@JsonSerialize(using = Bean.class) //Bean 为实现类,Bean需要继承JsonSerializer<>,泛型就是作用字段的类型。

{
    name: null,
    age: 22,
    sex: 'man'
}

{
    age: 22,
    sex: 'man'
}

@TableId(type = IdType.ASSIGN_ID)
	@JsonSerialize(using = ToStringSerializer.class)
	@ApiModelProperty(value = "id")
	private Long id;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import java.io.IOException;
import java.util.Date;
//继承JsonSerializer
public class DateJsonSerialize extends JsonSerializer<Date> {
    //重写serialize方法
    @Override
    public void serialize(Date date, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
        //自定义处理方式
        jsonGenerator.writeString("未完成");
    }
}

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import java.io.IOException;
public class BeanSerializer extends JsonSerializer<MyBeanClass> {
    @Override
    public void serialize(MyBeanClass bean, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
        // 在这里实现你自定义的序列化逻辑
        // 使用 jsonGenerator 将对象的属性按照你的需求写入 JSON
    }
}

@Data
@JsonSerialize(using = BeanSerializer.class)//①放到这
public class MyBeanClass {
    @JsonSerialize(using = BeanSerializer.class)//②放到这
    private String name;
}