Java XML，正式和实际参数的数量不同，或者解包转换失败

Question

使用accept: application/xml从端点请求数据时，我不断收到以下错误：

  

javax.xml.bind.MarshalException     - 链接异常：[Exception [EclipseLink-27]（Eclipse Persistence Services - 2.6.1.v20150916-55dc7c3）：   org.eclipse.persistence.exceptions.DescriptorException异常   描述：尝试在对象上调用方法[getSurveyid]   [com.on24.ejb.mapping.SurveyQuestion]。实际数量和   形式参数不同，或者解包转换失败。   内部异常：java.lang.IllegalArgumentException：对象不是   声明类映射的实例：   org.eclipse.persistence.oxm.mappings.XMLDirectMapping [surveyid - ＆GT; surveyid /文本（）]   描述符：XMLDescriptor（com.on24.ejb.mapping.Survey - ＆gt;   [DatabaseTable（调查）]）]

accept: application/json时响应正常，所以我知道从DB中提取信息不是问题;我只是无法解决这个问题所以任何帮助将不胜感激。

涉及的DTO：

@XmlRootElement
@XmlType (propOrder={"surveyid",
"surveyquestions"})
@XmlAccessorType(XmlAccessType.PUBLIC_MEMBER)
public class Survey {
    private Long surveyid;
    private List<SurveyQuestion> surveyquestions;

    public Survey(){}

    public Long getSurveyid() {
        return surveyid;
    }

    public void setSurveyid(Long surveyid) {
        this.surveyid = surveyid;
    }

    @XmlElementWrapper(name="surveyquestionslist")
    @XmlElement(name="surveyquestion")
    public List<SurveyQuestion> getSurveyquestions() {
        return surveyquestions;
    }

    public void setSurveyquestions(List<SurveyQuestion> surveyquestions) {
        this.surveyquestions = surveyquestions;
    }
}

并且

@XmlRootElement
@XmlType (propOrder={"surveyquestionid",
"surveyquestion",
"surveyanswers"})
@XmlAccessorType(XmlAccessType.PUBLIC_MEMBER)
public class SurveyQuestion {
    private Long surveyquestionid;
    private String surveyquestion;
    private List<String> surveyanswers;


    public SurveyQuestion(){}

    public Long getSurveyquestionid() {
        return surveyquestionid;
    }

    public void setSurveyquestionid(Long surveyquestionid) {
        this.surveyquestionid = surveyquestionid;
    }

    public String getSurveyquestion() {
        return surveyquestion;
    }

    public void setSurveyquestion(String surveyquestion) {
        this.surveyquestion = surveyquestion;
    }

    @XmlElementWrapper(name="surveyanswerslist")
    @XmlElement(name="surveyanswer")
    public List<String> getSurveyanswers() {
        return surveyanswers;
    }

    public void setSurveyanswers(List<String> surveyanswers) {
        this.surveyanswers = surveyanswers;
    }
}

我已经尝试了几次从重构到使用XmlAccessType.PUBLIC_MEMBER, XmlAccessType.FIELD, XmlAccessType.PROPERTY的想法，但没有成功。

我真的很想知道为什么会产生这个错误。如果需要更多信息，我会根据要求添加，谢谢。