vtd-xml解析多次出现的元素

I'm trying to parse the following XML and create Java objects corresponding to the main elements:

我正在尝试解析以下XML并创建与主要元素对应的Java对象:

<bookCase>
   <material>wood</material>
   <shelves>12</shelves>
   ...
   <listOfBooks>
      <book name="book1">
         <author>someone</author>
         <pages>200</pages>
         ...
      </book>
      <book name="book2">
         <author>someone else</author>
         <pages>500</pages>
         ...
      </book>
</bookCase>

So I want to create Java objects BookCase, which contains a List of Book objects.

所以我想创建Java对象BookCase,它包含一个Book对象列表。

I'm trying to use AutoPilot with XPath, but although I can get to the main values (material="wood", shelves="12"), I don't know how to iterate through the listOfBooks and create the two Book objects. Any idea?

我正在尝试使用带XPath的AutoPilot,但是虽然我可以获得主要值(material =“wood”,shelf =“12”),但我不知道如何遍历listOfBooks并创建两个Book对象。任何想法?

With the simple method below I can fetch the index of the two Book elements, but what do I with them?

通过下面的简单方法,我可以获取两个Book元素的索引,但是我对它们有什么看法?

private List<Integer> getBooksNodes() throws VTDException {
    final String xpath = "/bookCase/listOfBooks/book";
    ap.selectXPath(xpath);
    final List<Integer> nodeList = new ArrayList<>();
    int node;
    while ((node = ap.evalXPath()) != -1) nodeList.add(node);
    ap.resetXPath();
    return nodeList;
}

How do I tell the AutoPilot to explore the values for the XPath "author" and "pages" for each book individually so I can create a Book object each time AutoPilot has finished exploring that section?

如何告诉AutoPilot单独浏览每本书的XPath“作者”和“页面”的值,以便每次AutoPilot完成探索该部分时我都可以创建一个Book对象?

1 个解决方案

#1

Ok, below is the code for exploring the author and pages nodes... I am not making the assumption that the book node must have author or pages nodes...

好的,下面是探索作者和页面节点的代码......我没有假设书籍节点必须有作者或页面节点......

private List<Integer> getBooksNodes(VTDNav vn) throws VTDException {
    final String xpath = "/bookCase/listOfBooks/book";
    ap.selectXPath(xpath);
    final List<Integer> nodeList = new ArrayList<>();
    int node;
    while ((node = ap.evalXPath()) != -1) {
        nodeList.add(node);
        // the logic that browses the pages and author nodes
        // just print em out...
        // remember vn is automatically moved to the xpath output by  
        // autoPilot
        // we are gonna move the cursor manually now
        if (vn.toElement(FIRST_CHILD,"author")){
           int i = vn.getText();
           if (i!=-1)
              System.out.println(" author is ====>" + vn.toString(i));
           vn.toElement(PARENT);
        }

        if (vn.toElement(FIRST_CHILD,"pages")){
           int i = vn.getText();
           if (i!=-1)
              System.out.println(" author is ====>" + vn.toString(i));
           vn.toElement(PARENT);
        }

        // also remember that in a xpath eval loop, if you are gonna 
        // move the cursor manually
        // the node position going into the cursor logic must be identical 
        // to the node position existing the cursor logic
        // an easy way to accomplish this is 
        // vn.push() ;
        // your code that does manual node traversal
        // vn.pop();
        // but the logic above didn't use them
        // because move cursor to child, then moving back, essentially move 
        // the cursor to the original position
    }
    ap.resetXPath();
    return nodeList;
}