杰克逊在编组 JSON 时忽略 XmlElement 名称/大小写

Question

我正在尝试从 XSD->POJO->JSON 使用区分大小写的 UPS 跟踪 API。我在生成的 JSON 中使用 Jackson 2.6.7。当我应该在下面看到时，我会看到骆驼案例名称：

"TrackRequest": { "InquiryNumber": "1Z12345E6205277936" }

生成的 Java bean 如下注解：

@XmlElement(name = "TrackRequest")
protected TrackRequest trackRequest;

我尝试了一些映射功能设置，例如 USE_WRAPPER_NAME_AS_PROPERTY_NAME 和 USE_STD_BEAN_NAMING，但似乎没有达到预期的效果。

我正在像这样生成 JSON：

ObjectMapper mapper = new ObjectMapper();
String jsonRequest = mapper.writeValueAsString(upsRequest);

upsRequest bean 如下所示：

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = {
    "upsSecurity",
    "trackRequest"
})
@XmlRootElement(name = "Request")
public class Request {

    @XmlElement(name = "UPSSecurity")
    protected UPSSecurity upsSecurity;
    @XmlElement(name = "TrackRequest")
    protected TrackRequest trackRequest;

    /**
     * Gets the value of the upsSecurity property.
     * 
     * @return
     *     possible object is
     *     {@link UPSSecurity }
     *     
     */
    public UPSSecurity getUPSSecurity() {
        return upsSecurity;
    }

    /**
     * Sets the value of the upsSecurity property.
     * 
     * @param value
     *     allowed object is
     *     {@link UPSSecurity }
     *     
     */
    public void setUPSSecurity(UPSSecurity value) {
        this.upsSecurity = value;
    }

    /**
     * Gets the value of the trackRequest property.
     * 
     * @return
     *     possible object is
     *     {@link TrackRequest }
     *     
     */
    public TrackRequest getTrackRequest() {
        return trackRequest;
    }

    /**
     * Sets the value of the trackRequest property.
     * 
     * @param value
     *     allowed object is
     *     {@link TrackRequest }
     *     
     */
    public void setTrackRequest(TrackRequest value) {
        this.trackRequest = value;
    }

}

根据文档，我应该得到想要的输出，除非我遗漏了什么

Answer 1

要使用此功能读取spring-boot 及其Jackson2ObjectMapperBuilder 中的@JsonProperty 和XmlElement，您可以轻松地创建一个Bean，以便在每次需要时获取Builder。

@Bean
public Jackson2ObjectMapperBuilder jacksonBuilder() {
    Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
    //configure features for serialization and deserialization
    return builder;
}

您现在可以自动装配构建器并在需要的地方直接配置 ObjectMapper：

@Component
public class MyClass {

    private ObjectMapper objectMapper;

    public MyClass(Jackson2ObjectMapperBuilder jacksonBuilder) {
        super();
        objectMapper = jacksonBuilder.build().registerModule(new JaxbAnnotationModule());
    }

    public String serialize(){
        AnyObject ao = new AnyObject();
        String json = objectMapper.writeValueAsString(ao);
        return json;
    }
}

Answer 2

默认情况下不支持 JAXB 注释。您需要添加jackson-module-jaxb-annotations 模块，然后将其注册到ObjectMapper。

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JaxbAnnotationModule());

Answer 3

如评论中所述，将@JsonProperty 添加到字段中。

使用 Jackson 2.7.0 对我来说效果很好：

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = { "trackRequest" })
@XmlRootElement(name = "Request")
class Request {

    @XmlElement(name = "TrackRequest")
    @JsonProperty("TrackRequest")
    private TrackRequest trackRequest;

    public Request() {
    }
    public Request(TrackRequest trackRequest) {
        this.trackRequest = trackRequest;
    }
}

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = { "inquiryNumber" })
class TrackRequest {

    @XmlElement(name = "InquiryNumber")
    @JsonProperty("InquiryNumber")
    private String inquiryNumber;

    public TrackRequest() {
    }
    public TrackRequest(String inquiryNumber) {
        this.inquiryNumber = inquiryNumber;
    }
}

测试

Request upsRequest = new Request(new TrackRequest("1Z12345E6205277936"));

Marshaller marshaller = JAXBContext.newInstance(Request.class).createMarshaller();
marshaller.setProperty("jaxb.formatted.output", Boolean.TRUE);
marshaller.marshal(upsRequest, System.out);

ObjectMapper mapper = new ObjectMapper();
mapper.enable(SerializationFeature.INDENT_OUTPUT);
mapper.writeValue(System.out, upsRequest);

输出

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Request>
    <TrackRequest>
        <InquiryNumber>1Z12345E6205277936</InquiryNumber>
    </TrackRequest>
</Request>

{
  "TrackRequest" : {
    "InquiryNumber" : "1Z12345E6205277936"
  }
}

XML 和 JSON 输出都使用PascalCase。