I would like to insert a node in an xml file using Java DOM. I am actually editing a lot of contents of a dummy file in order to mofidy it like the original.
I would want to add an open node and close node in between the following file;
<?xml version="1.0" encoding="utf-8"?>
<Memory xmlns:xyz="http://www.w3.org/2001/XMLSchema-instance"
xmlns:abc="http://www.w3.org/2001/XMLSchema" Derivative="ABC"
xmlns="http://..">
///////////<Address> ///////////(which I would like to insert)
<Block ---------
--------
-------
/>
////////// </Address> /////////(which I would like to insert)
<Parameters Thread ="yyyy" />
</Memory>
I hereby request you to let me know how to I insert -- in between the xml file?
Thanks in advance.!
What I have tried doing is;
Element child = doc.createElement("Address");
child.appendChild(doc.createTextNode("Block"));
root.appendChild(child);
But this gives me an output like;
<Address> Block </Address> and not the way i expect :(
And now, what I have tried is to add these lines;
Element cd = doc.createElement("Address");
Node Block = root.getFirstChild().getNextSibling();
cd.appendChild(Block);
root.insertBefore(cd, root.getFirstChild());
But still, this is not the output which i am looking for. I got this output as
---------
What you want is probably:
Node parent = block.getParentNode()
Node blockRemoved = parent.removeChild(block);
// Create address
parent.appendChild(address);
address.appendChild(blockRemoved);
This is the standard way to re-attach a node in another place under W3C DOM.
Here:
DocumentBuilder b = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document document = b.parse(...);
// Parent of existing Block elements and new Address elemet
// Might be retrieved differently depending on
// actual structure
Element parent = document.getDocumentElement();
Element address = document.createElement("address");
NodeList nl = parent.getElementsByTagName("Block");
for (int i = 0; i < nl.getLength(); ++i) {
Element block = (Element) nl.item(i);
if (i == 0)
parent.insertBefore(address, block);
parent.removeChild(block);
address.appendChild(block);
}
// UPDATE: how to pretty print
LSSerializer serializer =
((DOMImplementationLS)document.getImplementation()).createLSSerializer();
serializer.getDomConfig().setParameter("format-pretty-print", Boolean.TRUE);
LSOutput output =
((DOMImplementationLS)document.getImplementation()).createLSOutput();
output.setByteStream(System.out);
serializer.write(document, output);
I assume you are using the W3C DOM (e.g. http://www.w3.org/TR/REC-DOM-Level-1/level-one-core.html ). If so try
insertBefore(address, block);
Related
Does anybody know, how to find self closing tags of the XML document?
I am able to get all the elements of specific type, but I am unable to find elements, that are self closing and also, I need to find elements, with no attributes.
var dbf = DocumentBuilderFactory.newInstance();
dbf.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
var db = dbf.newDocumentBuilder();
var urlToFile = MyClass.class.getClassLoader().getResource("file.xml");
var file = Paths.get(urlToFile .toURI()).toFile();
var doc = db.parse(file);
doc.getDocumentElement().normalize();
var list = doc.getElementsByTagName("myTag");
for (int i = 0; i < list.getLength(); i++) {
var node = list.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
var bits = node.getChildNodes();
for (int j = 0; j < bits.getLength(); j++) {
if (bits.item(j).hasAttributes()) {
// var parrentAttrName = bits.item(j).getNodeName();
// getValueFromAttribute is my private method
var nameAttrValue = getValueFromAttribute(bits, j, "name");
var stateAttrValue = getValueFromAttribute(bits, j, "state");
bits.addElementToList(new MyBit(nameAttrValue, stateAttrValue));
}
if(!bit.item(j).hasAttributes()) {
// not working
System.out.println(bits.item(j));
}
}
}
}
My XML file has two types of myTag tags:
Pair tags, that contains another nested child elements <myTag><someElementHere /></myTag>
Self-closing tags, that are specifying some other behaviour <myTag/>
Is there a mechanism, to find this kind elements? The one possible thing would be, to match the regex of self closing tags, but I was thinking of some other solution possible.
Once the document is parsed, and the content loaded into a DOM, there are no tags, there are only nodes. You can tell that an element node is empty (by asking whether it has any child nodes), but you can't tell whether the empty element was originally written as <myTag/> or as <myTag></myTag>. That's the author's choice and it should make no difference to the recipient.
Your question indicates that you are very confused about the difference between the lexical XML (the tags and angle brackets), and the tree model of the XML represented by the DOM.
Self closing tags have no children but so do empty tags.
That said, XPath could be used to find elements with no children or with attributes
Given
<?xml version="1.0" encoding="UTF-8"?>
<root>
<test/>
<test a="a"/>
<empty></empty>
<test>
<a>a</a>
</test>
<test>text</test>
<deep>
<some b="b" />
</deep>
</root>
Find elements with no children with //*[count(./descendant::*) = 0 and count(./text()) = 0]
xmllint --shell test.xml
</ cat //*[count(./descendant::*) = 0 and count(./text()) = 0]
<test/>
-------
<test a="a"/>
-------
<empty/>
-------
<some b="b"/>
Find elements with attributes with xpath //*[count(./#*)> 0]
/ > cat //*[count(./#*)> 0]
-------
<test a="a"/>
-------
<some b="b"/>
Note: XPath is language agnostic so it should work in java.
Essentially, i'm creating an XML document from a file (a database), and then i'm comparing another parsed XML file (with updated information) to the original database, then writing the new information into the database.
I'm using java's org.w3c.dom.
After lots of struggling, i decided to just create a new Document object and will write from there from the oldDocument and newDocument ones i'm comparing the elements in.
The XML doc is in the following format:
<Log>
<File name="something.c">
<Warning file="something.c" line="101" column="23"/>
<Warning file="something.c" line="505" column="71" />
</File>
</Log>
as an example.
How would i go about adding in a new "warning" Element to the "File" without getting the pesky "org.w3c.dom.DOMException: WRONG_DOCUMENT_ERR: A node is used in a different document than the one that created it." exception?
Cutting it down, I have something similar to:
public static Document update(Element databaseRoot, Element newRoot){
Document doc = db.newDocument(); // DocumentBuilder defined previously
Element baseRoot = doc.createElement("Log");
//for each file i have:
Element newFileRoot = doc.createElement("File");
//some for loop that parses through each 'file' and looks at the warnings
//when i come to a new warning to add to the Document:
NodeList newWarnings = newFileToCompare.getChildNodes(); //newFileToCompare comes from the newRoot element
for (int m = 0; m < newWarnings.getLength(); m++){
if(newWarnings.item(m).getNodeType() == Node.ELEMENT_NODE){
Element newWarning = (Element)newWarnings.item(m);
Element newWarningRoot = (Element)newWarning.cloneNode(false);
newFileRoot.appendChild(doc.importNode(newWarningRoot,true)); // this is what crashes
}
}
// for new files i have this which works:
newFileRoot = (Element)newFiles.item(i).cloneNode(true);
baseRoot.appendChild(doc.importNode(newFileRoot,true));
doc.appendChild(baseRoot);
return doc;
}
Any ideas? I'm beating my head against the wall. First time doing this.
Going through with a debugger I verified that the document owners were correct. Using node.getOwnerDocument(), I realized that the newFileRoot was connected to the wrong document earlier when I created it, so I changed
Element newFileRoot = (Element)pastFileToFind.cloneNode(false);
to
Element newFileRoot = (Element)doc.importNode(pastFileToFind.cloneNode(false),true);
since later on when i was trying to add the newWarningRoot to newFileRoot, they had different Documents (newWarningRoot was correct but newFileRoot was connected to the wrong document)
<root>
<h id="1">
<d value="1,2,3,4,5"><open>10:00</open><close>23:00</close></d>
<d value="6"><open>10:00</open><close>2:00</close></d>
<d value="7"><open>10:00</open><close>21:00</close></d>
</h>
<h id="2">
</h>
</root>
Here I have the XML which root has list of <h> tagged nodes. Now I need to break these into parts and set it into different variables (add into a map).
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(new InputSource(new ByteArrayInputStream(data.getBytes("utf-8"))));
NodeList nList = doc.getElementsByTagName("h");
for (int i = 0; i < nList.getLength(); i++)
{
Node nNode = nList.item(i);
System.out.println(nNode.getAttributes().getNamedItem("id") + " " + ?????);
}
what should I call in order to get the value (String value) of a nNode ?
Here is what Im looking for as the asnwer for the above code once some one fills the ????
1 <h id="1"><d value="1,2,3,4,5"><open>10:00</open><close>23:00</close></d><d value="6">open>10:00</open><close>2:00</close></d><d value="7"><open>10:00</open><close>21:00</close></d></h>
2 <h id="2"></h>
And i don't mind having as root element
You can use Node.getTextContent() to conveniently get all the text of a node (gets text of children as well).
See Parsing xml file contents without knowing xml file structure for a short example.
If you're trying to get the value attributes of the d nodes (I can't actually tell, your question is slightly unclear to me), then it would be different -- for that you would iterate through the children of each h node (use getChildNodes() or getFirstChild() + getNextSibling()) then grab their value attributes just as you are getting the id attribute of the h nodes (the above link also shows an example of iterating through child nodes).
Have you tried jDom library? http://www.jdom.org/docs/apidocs/org/jdom2/output/XMLOutputter.html
XMLOutputter outp = new XMLOutputter();
String s = outp.outputString(your_jdom_element);
Have you tried nNode.toString() if you are using Node from javax.xml.soap.Node.
You can use that:
http://docs.oracle.com/javase/7/docs/api/org/w3c/dom/Node.html#getTextContent()
but your sample nNode has other nodes, not just text. It seems you need helper method to construct String from child nodes.
Pass your nNode to nodeToString
XML Node to String in Java
I am new to read XML in Java using DOM. Could someone help me with simple code steps to read this XML in DOM?
Here is my XML:
<DataSet xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xsi:noNamespaceSchemaLocation='datamartschema.1.3.xsd'>
<DataStream title='QUESTIONNAIRE'>
<Record>
<TransactionDate>2014-05-28T14:17:31.2186777-06:00</TransactionDate><SubType>xhaksdj</SubType>
<IntegerValue title='ComponentID'>11111</IntegerValue>
</Record><Record>
<TransactionDate>2014-05-28T14:17:31.2186777-06:00</TransactionDate><SubType>jhgjhg</SubType>
<IntegerValue title='ComponentID'>11111</IntegerValue>
</Record>
</DataStream>
</DataSet>
In this XML I need to read the DataStream value and Record values. My expected output is
DataStream=QUESTIONNAIRE and my records are
<TransactionDate>2014-05-28T14:17:31.2186777-06:00</TransactionDate><SubType>xhaksdj</SubType><IntegerValue title='ComponentID'>11111</IntegerValue><TransactionDate>2014-05-28T14:17:31.2186777-06:00</TransactionDate><SubType>jhgjhg</SubType><IntegerValue title='ComponentID'>11111</IntegerValue>
How can I get this output? I tried myself but I can't get the records output like above. I get the output without Tags which are present in the above output.I am using this line to get the output. But it does not give me correct output. Also, how to read the datastream value from this XML? Kindly help me.
This is my code snippets
NodeList datasetallRecords = indElement.getElementsByTagName("Record");
for (int y = 0; y < datasetallRecords.getLength(); y++) {
Element recordsElement = (Element) datasetallRecords.item(y);
recordXMl = recordXMl + recordsElement.getTextContent();
String d = datasetallRecords.item(y).getTextContent();
if (recordsElement.getTagName().equalsIgnoreCase("SubType")) {
lsDataStreamSubTypes.add(recordsElement.getTextContent());
}
recordCount = y;
}
When you create new instance of builder you can get DataStream
it would be look like this:
Element root = document.getDocumentElement();
NodeList dataStreams = root.getElementsByTagName("DataStream");
then get throw this list and get all info like this:
for (int i = 0; i < dataStreams.lenght(); i++) {
Element dataStream = (Element) dataStreams.item(i);
if (dataStream.getNodeType() == Element.ELEMENT_NODE) {
String title = dataStream.getAttributes()
.getNamedItem("title").getTextContent();
}
}
First you need to create a Node like this
Node nNode = datasetallRecords.item(y);
then an element like this
Element eElement = (Element) nNode;
now you can start taking the values from the element by using the getelementbyid and getnodevalue method.
You're not getting the tags because the call to getTextContent() on the "Record" node will return only the textual content of that node and its descendants.
If you need to nodes as well you'll have to process the XML by hand. Have a look at the DOM tutorial it covers processing a document in DOM mode very well including how to read out element names.
I have a tiny little problem parsing an XML file in Java (Android).
I have an XML file that is like this:
<Events>
<Event Name="Olympus Has Fallen">
...
</Event>
<Event Name="Iron Man 3">
...
</Event>
</Events>
I already managed to get the NodeList by doing this:
URL url = new URL("********");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(url.openStream()));
doc.getDocumentElement().normalize();
NodeList nodeList = doc.getElementsByTagName("Event");
Also I managed to get every single item of the NodeList by doing this:
for (int i = 0; i < nodeList.getLength(); i++) {
// Item
Node node = nodeList.item(i);
Log.i("film", node.getNodeName());
}
But this just Logs: "Event" instead of the value of the Name tag.
How do I output the value of this 'name' tag from the XML.
Can anyone help me with this one?
Thanks in advance!
But this just Logs: "Event" instead of the value of the Name tag.
Yes, because you're asking for the name of the element. There isn't a Name "tag" - there's a Name attribute, and that's what you should find:
// Only check in elements, and only those which actually have attributes.
if (node.hasAttributes()) {
NamedNodeMap attributes = node.getAttributes();
Node nameAttribute = attributes.getNamedItem("Name");
if (nameAttribute != null) {
System.out.println("Name attribute: " + nameAttribute.getTextContent());
}
}
(It's very important to be precise in terminology - it's worth knowing the difference between nodes, elements, attributes etc. It will help you enormously both when communicating with others and when looking for the right bits of API to call.)