Replacing XML node via Java

Question

I wan to replace a node in XML document with another and as a consequence replace all it's children with other content. Following code should work, but for an unknown reason it doesn't.

File xmlFile = new File("c:\\file.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(xmlFile);
doc.getDocumentElement().normalize();

NodeList nodes = doc.getElementsByTagName("NodeToReplace");
for (int i = 0; i < nodes.getLength(); i++) {

    NodeList children = nodes.item(i).getChildNodes();
    for (int j = 0; j < children.getLength(); j++) {
          nodes.item(i).removeChild(children.item(j));
    }
        doc.renameNode(nodes.item(i), null, "MyCustomTag");  
}

EDIT-

After debugging it for a while, I sovled it. The problem was in moving index of the children array elmts. Here's the code:

NodeList nodes = doc.getElementsByTagName("NodeToReplace");
for (int i = 0; i < nodes.getLength(); i++) {

    NodeList children = nodes.item(i).getChildNodes();

    int len = children.getLength();
    for (int j = len-1; j >= 0; j--) {
        nodes.item(i).removeChild((Node) children.item(j));
    }
    doc.renameNode(nodes.item(i), null, "MyCustomTag");  
}

"for an unknown reason it doesn't" is not helpful. What does it do? Nothing at all? Throws an Exception? Makes egg and bacon? — Vala
– Vala, Commented Oct 26, 2011 at 14:24
Do you have to manually remove the children? Is it not possible to just replace the node with the one you want to have? — hellectronic
– hellectronic, Commented Oct 26, 2011 at 14:25
It renames the node, but it fails in deleting it's childern and I can't find the bug in it. — Ondrej Sotolar
– Ondrej Sotolar, Commented Oct 26, 2011 at 14:26
He's renaming the node rather than deleting and creating a new one, I presume that's why he's trying to remove children as well. Are you doing it this way because you want to make sure they are in exactly the same place? — Vala
– Vala, Commented Oct 26, 2011 at 14:27

nochum · Accepted Answer · 2014-11-25 06:52:19Z

12

Try using replaceChild to do the whole hierarchy at once:

NodeList nodes = doc.getElementsByTagName("NodeToReplace");
for (int i = 0; i < nodes.getLength(); i++) {
    Node node = nodes.item(i);
    Node newNode = // Create your new node here.
    node.getParentNode().replaceChild(newNode, node);
}

edited Nov 25, 2014 at 6:52

nochum

7554 silver badges10 bronze badges

answered Oct 26, 2011 at 14:32

Vala

5,7041 gold badge32 silver badges56 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Vala Over a year ago

There are a few ways, you'd probably want to use doc.createTextNode(String) to create a template node and then clone that for each newNode.

Venkat · Accepted Answer · 2018-11-11 05:55:08Z

-3

Easy way to do is using regular expression.

String payload= payload.replaceAll("<payload>([^<]*)</payload>", "<payload>NODATA</payload>");

This will make sure all the payload nodes contents are replaced with NODATA

answered Nov 11, 2018 at 5:55

Venkat

3425 silver badges10 bronze badges

1 Comment

him Over a year ago

structural string manipulation should be avoided with XML because it ignores things like hierarchy, context, and other semantics that xml enforces. assuming an XML file is a flat string is sure to create more headaches than it is worth

Collectives™ on Stack Overflow

Replacing XML node via Java

2 Answers 2

1 Comment

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related