使用 Jackson 序列化枚举 [英] Serializing enums with Jackson

问题描述

我有一个枚举如下:

公共枚举 OrderType {未知(0，未定义")，TYPEA(1, "类型 A"),TYPEB(2, "B 型"),TYPEC(3, "Type C");私有整数 ID；私人字符串名称；私人工作订单类型(整数 ID，字符串名称){this.id = id;this.name = 名称；}//设置器，获取器....}

我用我的控制器返回枚举数组(new OrderType[] {UNKNOWN,TYPEA,TYPEB,TYPEC};)，Spring 将其序列化为以下 json 字符串:

["UNKNOWN", "TYPEA", "TYPEB", "TYPEC"]

强制 Jackson 像 POJO 一样序列化枚举的最佳方法是什么?例如:

<预><代码>[{"id": 1, "name": "未定义"},{"id": 2, "name": "Type A"},{"id": 3, "name": "Type B"},{"id": 4, "name": "Type C"}]

我使用了不同的注释，但无法获得这样的结果.

解决方案

最后我自己找到了解决方案.

我必须用 @JsonSerialize(using = OrderTypeSerializer.class) 注释枚举并实现自定义序列化器:

公共类 OrderTypeSerializer 扩展 JsonSerializer{@覆盖public void serialize(OrderType 值，JsonGenerator 生成器，SerializerProvider 提供者)抛出 IOException，JsonProcessingException {generator.writeStartObject();generator.writeFieldName("id");generator.writeNumber(value.getId());generator.writeFieldName("name");generator.writeString(value.getName());generator.writeEndObject();}}

I have an Enum desrcibed below:

public enum OrderType {

  UNKNOWN(0, "Undefined"),
  TYPEA(1, "Type A"),
  TYPEB(2, "Type B"),
  TYPEC(3, "Type C");

  private Integer id;
  private String name;

  private WorkOrderType(Integer id, String name) {
    this.id = id;
    this.name = name;
  }

  //Setters, getters....
}

I return enum array with my controller ( new OrderType[] {UNKNOWN,TYPEA,TYPEB,TYPEC};), and Spring serializes it into the following json string:

["UNKNOWN", "TYPEA", "TYPEB", "TYPEC"] 

What is the best approach to force Jackson to serialize enums just like POJOs? E.g.:

[
  {"id": 1, "name": "Undefined"},
  {"id": 2, "name": "Type A"},
  {"id": 3, "name": "Type B"},
  {"id": 4, "name": "Type C"}
]

I played with different annotations but couldn't manage to get such result.

解决方案

Finally I found solution myself.

I had to annotate enum with @JsonSerialize(using = OrderTypeSerializer.class) and implement custom serializer:

public class OrderTypeSerializer extends JsonSerializer<OrderType> {

  @Override
  public void serialize(OrderType value, JsonGenerator generator,
            SerializerProvider provider) throws IOException,
            JsonProcessingException {

    generator.writeStartObject();
    generator.writeFieldName("id");
    generator.writeNumber(value.getId());
    generator.writeFieldName("name");
    generator.writeString(value.getName());
    generator.writeEndObject();
  }
}

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