jackson - com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.lang.String out of START_OBJECT token

Question

when deserializing below JSON, it fails with above exception message when trying to parse the server attribute which has its type 'string' nested within it, how to parse a JSON which is having the attribute types nested within each attribute like below?

{
  "header": {
    "time": 1492178674232,
    "threadId": null,
    "requestMarker": null,
    "env": null,
    **"server": {
      "string": "astapp078"
    }**,
    "service": {
      "string": "ApiCalendarsEntityStreamPublisher"
    }
  }
}

Answer 1

您可以使用@JsonProperty注释为 JSON 字段指定与 POJO 字段不同的名称。server并将andservice字段包装在类中。例如

class POJO {
    Server server;
    Service service;
}

class Server {
    @JsonProperty("string") String name;
}

class Service {
    @JsonProperty("string") String name;
}

name会server是_"astapp078"