Scala:将org.w3c.dom.Document转换为scala.xml.NodeSeq

时间:2010-10-13 09:05:27

标签: java xml dom scala

标题非常明显。如何将org.w3c.dom.Document的实例转换为Scala NodeSeq,以享受它的便利?

干杯
伯尔萨

4 个答案:

答案 0 :(得分:12)

  def asXml(dom: org.w3c.dom.Node): Node = {
    val dom2sax = new DOM2SAX(dom)
    val adapter = new NoBindingFactoryAdapter
    dom2sax.setContentHandler(adapter)
    dom2sax.parse()
    return adapter.rootElem
  }

答案 1 :(得分:5)

IttayD的答案适用于所有w3c XML - 除了dom4j w3c兼容的xmls。以下适用于所有w3c类型:

def asXml(dom: _root_.org.w3c.dom.Node): Node = {
    val source = new DOMSource(dom)
    val adapter = new NoBindingFactoryAdapter
    val saxResult = new SAXResult(adapter)
    val transformerFactory = javax.xml.transform.TransformerFactory.newInstance()
    val transformer = transformerFactory.newTransformer()
    transformer.transform(source, saxResult)
    adapter.rootElem
  }

答案 2 :(得分:3)

我将这段代码写回了另一个方向,从Scala节点到Dom4J节点。它显示了在树上递归的基本思想,并且应该很容易适应:

implicit def scalaToDom4j(n : Node) : DElem = {

  def inner(n : Node) : Option[DNode] = {
    n match {
      case e : Elem =>
        val elem = DocumentHelper.createElement(e.label)
        for(c <- e.child) yield inner(c) collect {
          case Some(child) => elem.add(child)
        }
        Some(elem)
        //as Scala's xml is type-aware, text might not actually be a Text node,
        //but an Atom of some other type
      case t : Atom[_] =>
        Some(DocumentHelper.createText(t.data.toString))
      case x => None
    }
  }

  //Attempt the conversion. Throw an exception if something has gone badly wrong
  //inner returns an Option[DNode], but the expected top-level type is a DElem
  // (which is a subclass of DNode)
  //so we also validate this.
  inner(trim(n)) map (_.asInstanceOf[DElem]) getOrElse (error("xml failed"))
}

答案 3 :(得分:0)

我有与上面的scalaToDom4j(n)函数类似的递归模式匹配代码,仅在Saxon XdmNode到Scala Node方向上: https://github.com/LeifW/MusicPath/blob/master/src/main/scala/org/musicpath/saxon2scala/Saxon2Scala.scala

目前它只生成Text,Element和非命名空间的Attribute节点,但它应该很容易概括/完成。