jackson转换list时遇到问题.出现重复。看回答里的截图

```@JsonAutoDetect(fieldVisibility = JsonAutoDetect.Visibility.NONE)
@JsonRootName("xml")
public class NewsRespMessage {
@JacksonXmlProperty
private String ToUserName;
@JacksonXmlProperty
private String FromUserName;
@JacksonXmlProperty
private int CreateTime;
@JacksonXmlProperty
private String MsgType;
@JacksonXmlProperty
private int ArticleCont;

@JacksonXmlProperty
private Articles Articles;

public NewsRespMessage(String toUserName, String fromUserName, int createTime, String msgType, int articleCont, com.example.entity.media.Articles articles) {
    ToUserName = toUserName;
    FromUserName = fromUserName;
    CreateTime = createTime;
    MsgType = msgType;
    ArticleCont = articleCont;
    Articles = articles;
}

}

@JsonAutoDetect(fieldVisibility = JsonAutoDetect.Visibility.NONE)
@JsonRootName("Articles")
public class Articles {
@JacksonXmlProperty
private List item;
public Articles(List item) {
this.item = item;
}
}

@JsonAutoDetect(fieldVisibility = JsonAutoDetect.Visibility.NONE)
public class item {
@JacksonXmlProperty
private String Title;
@JacksonXmlProperty
private String Description;
@JacksonXmlProperty
private String PicUrl;
@JacksonXmlProperty
private String Url;

public item(String title, String description, String picUrl, String url) {
    Title = title;
    Description = description;
    PicUrl = picUrl;
    Url = url;
}

}

![重复](https://img-ask.csdn.net/upload/201703/13/1489408724_389426.png)
怎么写才能不让item标签重复