1

I'm trying to modify an XML document using DOM by replacing some Elements in it, but I'm getting the following Exception:

03-10 10:49:20.943: W/System.err(22584):    org.w3c.dom.DOMException
03-10 10:49:20.943: W/System.err(22584):    at org.apache.harmony.xml.dom.InnerNodeImpl.insertChildAt(InnerNodeImpl.java:118)
03-10 10:49:20.943: W/System.err(22584):    at org.apache.harmony.xml.dom.InnerNodeImpl.appendChild(InnerNodeImpl.java:52)

The XML document has the following hierarchy:

<?xml version="1.0" encoding="UTF-8"?>
<msg>
    <header>
        <method>Call</method>
    </header>
</msg>

And I'm trying to replace the Element header by another one using replaceChild() method:

doc.replaceChild(header, (Element)doc.getElementsByTagName("header").item(0));

but I'm getting the above Exception. So, I traced the Exception to see where it is got thrown and that led me to the following line in org.apache.harmony.xml.dom.InnerNodeImpl Class:

public Node removeChild(Node oldChild) throws DOMException {

    LeafNodeImpl oldChildImpl = (LeafNodeImpl) oldChild;
    if (oldChildImpl.document != document) {
        throw new DOMException(DOMException.WRONG_DOCUMENT_ERR, null);
    }

    if (oldChildImpl.parent != this) {
        throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, null); // This is where the Exception got thrown
    }

    int index = oldChildImpl.index;
    children.remove(index);
    oldChildImpl.parent = null;
    refreshIndices(index);
    return oldChild;

}

which means that it can't recognize the Element header as a child Element of the Document which is Incorrect, so, what am I missing here?!!

For reference, the following is my whole method I'm using in this process:

private void forming_and_sending_xml(String message, Element header){

    Document doc = null;
    try {
        doc = loadXMLFromString(message);
    } catch (Exception e) {
        e.printStackTrace();
    }
    doc.getDocumentElement().normalize();
    doc.replaceChild(header, (Element)doc.getElementsByTagName("header").item(0)); // this is where I got the Exception

}

UPDATE

I changed the way to replace the element, I used importNode to add the Node to the document and then I separated the replacement process to (remove -> add), which enabled me to fix all issues related to the remove process and now the Element is being removed successfully but the doc doesn't approve to add the new Element and it throws the same Exception that mentioned above.

My new method:

private void forming_and_sending_xml(String message, Element header){

    Document doc = null;
    try {
        doc = loadXMLFromString(message);
    } catch (Exception e) {
        e.printStackTrace();
    }
    doc.getDocumentElement().normalize();
    doc.importNode(header, true);
    Element header_holder = (Element)doc.getElementsByTagName("header").item(0);
    header_holder.getParentNode().removeChild(header_holder); // this removes the Element from the Doc succeffully
    doc.getDocumentElement().appendChild(header); // this is where the Exception is got thrown now

}
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1 回答 1

3

我想这里有两个错误：

  1. 必须将新<header>元素导入到现有文档中（如评论中所述），并且

  2. 该oldChild节点必须是上下文节点的直接子节点，而不是示例中的孙子节点。代替

    doc.replaceChild(header, (Element)doc.getElementsByTagName("header").item(0));

    和

    doc.getDoumentElement().
   replaceChild(doc.importNode(header, true), 
                (Element)doc.getElementsByTagName("header").item(0));
于 2016-03-10T11:42:03.933 回答