从json到包含枚举的对象的反序列化问题

Question

使用jackson2.9.8对枚举反序列化有问题。Gson也可以正常工作。模型是从swagger api定义自动生成的

使用Gson，效果很好。对于杰克逊来说，它不适用于011、013和019，但适用于其他值

Swagger api定义的片段

服务代码： 类型： 字符串枚举： - “001” - “002” - “003” - “004” - “005” - “007” - “008” - “009” - “011” - “013” - “019”

自动生成的代码（删除getter/setter的易读性）

public class ProcessErrorTest1 {
    static String errorJson =
            "    {\n" +
            "      \"timestamp\": \"2019-07-29 11:55:48\",\n" +
            "      \"serviceCode\": \"019\",\n" +
            "      \"message\": \"service failed. \",\n" +
            "      \"rootException\": {\n" +
            "        \"source\": \"test\",\n" +
            "        \"reasonCode\": \"2131\",\n" +
            "        \"reasonText\": \"test\"\n" +
            "      }\n" +
            "}";

    public static void main(String[] args) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        AppErrorResponse error = mapper.readValue(errorJson, AppErrorResponse.class);
       // Gson gson = new Gson();
        //AppErrorResponse error = gson.fromJson(errorJson, AppErrorResponse.class);
        System.out.println("error::" + error);
    }
}

public class AppErrorResponse {

  @SerializedName("message")
  private String message = null;

  @SerializedName("rootException")
  private ErrorResponse rootException = null;
  /**
   * Gets or Sets serviceCode
   */
  @JsonAdapter(ServiceCodeEnum.Adapter.class)
  public enum ServiceCodeEnum {
    _001("001"),
    _002("002"),
    _003("003"),
     _004("004"),
    _005("005"),
    _007("007"),
    _008("008"),
    _009("009"),
    _011("011"),
    _013("013"),
   // @JsonProperty("019") if add this , it works fine. But can't modify the auto generated code as it is available as jar
    _019("019");
  }
  @SerializedName("serviceCode")
  private ServiceCodeEnum serviceCode = null;

  @SerializedName("timestamp")
  private String timestamp = null;

}

public class ErrorResponse {

  @SerializedName("reasonCode")
  private String reasonCode = null;

  @SerializedName("reasonText")
  private String reasonText = null;

  @SerializedName("source")
  private String source = null;
}

jersey1:jackson生成的代码

import java.util.Objects;
import com.bt.consumer.appointment.dto.MAC2ErrorResponse;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonValue;
public class AppErrorResponse {
  @JsonProperty("message")
  private String message = null;

  @JsonProperty("rootException")
  private ErrorResponse rootException = null;

  public enum ServiceCodeEnum {
    _001("001"),
    _002("002"),
    _003("003"),
    _004("004"),
    _005("005"),
    _007("007"),
    _008("008"),
    _009("009"),
    _011("011"),
    _013("013"),
    _019("019");

    private String value;

    ServiceCodeEnum(String value) {
      this.value = value;
    }
    @JsonValue
    public String getValue() {
      return value;
    }

    @Override
    public String toString() {
      return String.valueOf(value);
    }
    @JsonCreator
    public static ServiceCodeEnum fromValue(String text) {
      for (ServiceCodeEnum b : ServiceCodeEnum.values()) {
        if (String.valueOf(b.value).equals(text)) {
          return b;
        }
      }
      return null;
    }

  }
  @JsonProperty("serviceCode")
  private ServiceCodeEnum serviceCode = null;

  @JsonProperty("timestamp")
  private String timestamp = null;
}

import java.util.Objects;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonValue;
public class ErrorResponse {
  @JsonProperty("reasonCode")
  private String reasonCode = null;

  @JsonProperty("reasonText")
  private String reasonText = null;

  @JsonProperty("source")
  private String source = null;
}

它适用于除 _011、_013 和 _019 之外的所有使用杰克逊错误 meessage：- com.fasterxml.jackson.databind.exc.InvalidFormatException：无法从字符串“011”中反序列化 ServiceCodeEnum 类型的值：值不是声明的枚举实例名称之一：[_011， _001， _002， _003， _004， _005， _007， _008， _009， _013， _019]

Answer 1

您的注释是针对Gson而不是Jackson的，您应该为Jackson而不是Gson生成pojos。行< code > @ JSON adapter(service code enum。Adapter.class)是为Gson处理该enum转换的适配器。

查看 swagger codegen 文档，您会发现有关生成 https://github.com/swagger-api/swagger-codegen#customizing-the-generator 的部分

据说：对于所有未指定的选项，将使用默认值。

上面列出了下表：

CONFIG OPTIONS
    modelPackage
        package for generated models

    apiPackage
        package for generated api classes
...... (results omitted)
    library
        library template (sub-template) to use:
        jersey1 - HTTP client: Jersey client 1.18. JSON processing: Jackson 2.4.2
        jersey2 - HTTP client: Jersey client 2.6
        feign - HTTP client: Netflix Feign 8.1.1.  JSON processing: Jackson 2.6.3
        okhttp-gson (default) - HTTP client: OkHttp 2.4.0. JSON processing: Gson 2.3.1
        retrofit - HTTP client: OkHttp 2.4.0. JSON processing: Gson 2.3.1 (Retrofit 1.9.0)
        retrofit2 - HTTP client: OkHttp 2.5.0. JSON processing: Gson 2.4 (Retrofit 2.0.0-beta2)
        google-api-client - HTTP client: google-api-client 1.23.0. JSON processing: Jackson 2.8.9
        rest-assured - HTTP client: rest-assured : 3.1.0. JSON processing: Gson 2.6.1. Only for Java8

这一行可能是正在使用的：

< code>okhttp-gson(默认)- HTTP客户端:OkHttp 2.4.0。JSON处理:Gson 2.3.1

您需要指定一个使用 Jackson 的库和一个您想要的 HTTP 客户端。