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Java Can';无法达到ArrayList内容_Java_Arraylist_Xstream - Fatal编程技术网

Java Can';无法达到ArrayList内容

Java Can';无法达到ArrayList内容,java,arraylist,xstream,Java,Arraylist,Xstream,我一直在使用Xsrteam将XML解析为ArrayList。它起作用了,但由于某种原因,我无法访问数组的内容 处理ArrayList数据的类: @XStreamAlias("BOARDS") public class Boards { @XStreamImplicit(itemFieldName = "id") public ArrayList ids = new ArrayList(); //region GETTERS-SETTERS public void

我一直在使用Xsrteam将XML解析为ArrayList。它起作用了,但由于某种原因,我无法访问数组的内容

处理ArrayList数据的类:

@XStreamAlias("BOARDS")
public class Boards {
    @XStreamImplicit(itemFieldName = "id")
    public ArrayList ids = new ArrayList();

    //region GETTERS-SETTERS
    public void setIds(ArrayList temp){
        this.ids = temp;
    }
    public List getIds(){
        return ids;
    }
//    endregion
}

@XStreamAlias("id")
class Id {

    @XStreamAlias("board")
    private String board;

    @XStreamAlias("description")
    private String description;

    @XStreamAlias("price")
    private String price;

    @XStreamAlias("shape")
    private String shape;

    @XStreamAlias("riding_level")
    private String ridingLevel;

    @XStreamAlias("riding_style")
    private String ridingStyle;

    @XStreamAlias("camber_profile")
    private String camber;

    @XStreamAlias("stance")
    private String stance;

    @XStreamAlias("picture")
    private String picture;

    <<public getters - setters here>>
}
first
objectfirst=boards.getIds().get(0)

下面是使用调试器时的情况:


Boards
具有原始类型,因此不清楚
ArrayList ID中应包含哪些对象类型。因此,您应该显式地强制转换
boards.getIds().get(0)
的结果:

((Id) boards.getIds().get(0)).getPrice()
或泛化
类:

public class Boards<E> {

    public List<E> ids = new ArrayList<E>();

    //region GETTERS-SETTERS
    public void setIds(ArrayList<E> temp){
        this.ids = temp;
    }
    public List<E> getIds(){
        return ids;
    }
//    endregion
}
公共类董事会{
public List id=new ArrayList();
//区域GETTERS-SETTERS
公共无效集合ID(ArrayList temp){
此参数=温度;
}
公共列表getIds(){
返回ID;
}
//端区
}

你可以阅读有关泛型的文章

哦,原因总是很简单的。谢谢你的快速回复!
public class Boards<E> {

    public List<E> ids = new ArrayList<E>();

    //region GETTERS-SETTERS
    public void setIds(ArrayList<E> temp){
        this.ids = temp;
    }
    public List<E> getIds(){
        return ids;
    }
//    endregion
}