從json反序列化到包含枚舉的對象的問題

Question

使用jackson2.9.8進行枚舉反序列化時遇到問題。 Gson也可以正常工作。 模型是根據swagger API定義自動生成的

使用Gson，效果很好。 對於傑克遜，它不適用於011、013和019，但適用於其他值

Swagger API定義的摘要

serviceCode：類型：字符串枚舉：-“ 001”-“ 002”-“ 003”-“ 004”-“ 005”-“ 007”-“ 008”-“ 009”-“ 011”-“ 013”-“ 019 “

自動生成的代碼（刪除了getter / setter以提高可讀性）

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生成代碼

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;
}

使用jackson錯誤消息，它除_011，_013和_019以外的所有內容都正常工作：-com.fasterxml.jackson.databind.exc.InvalidFormatException：無法從字符串“ 011”反序列化ServiceCodeEnum類型的值：值不是聲明的Enum實例名稱之一：[_ 011，_001，_002，_003，_004，_005，_007，_008，_009，_013，_019]

Answer 1

您的注釋針對Gson而不是Jackson，您應該為Jackson而不是Gson生成pojos。 @JsonAdapter(ServiceCodeEnum.Adapter.class)是一個適配器，用於處理Gson的該枚舉的轉換。

---

查看swagger codegen文檔，您會找到有關生成https://github.com/swagger-api/swagger-codegen#customizing-the-generator的部分

據說： For all the unspecified options default values will be used.

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

這行可能是正在使用的內容：

okhttp-gson (default) - HTTP client: OkHttp 2.4.0. JSON processing: Gson 2.3.1

您需要指定一個庫，該庫使用Jackson和所需的HTTP客戶端。