Unable to delete a specific node in XML - java

I have an XML file and I need to delete a specific node. The node to be deleted will be defined dynamically based on the logic. I have been searching in internet for a solution but couldn't delete my node still. am getting error - NOT_FOUND_ERR: An attempt is made to reference a node in a context where it does not exist
Below is a sample XML File. I need to delete the node <NameValuePairs> which has <name>Local Variables</name>. Below is my sample XML Files Java Code
Sample XML File
<?xml version="1.0" encoding="UTF-8"?>
<DeploymentDescriptors xmlns="http://www.tibco.com/xmlns/dd">
<name>Test</name>
<version>1</version>
<DeploymentDescriptorFactory>
<name>RepoInstance</name>
</DeploymentDescriptorFactory>
<DeploymentDescriptorFactory>
<name>NameValuePairs</name>
</DeploymentDescriptorFactory>
<NameValuePairs>
<name>Global Variables</name>
<NameValuePair>
<name>Connections1</name>
<value>7222</value>
<requiresConfiguration>true</requiresConfiguration>
</NameValuePair>
<NameValuePair>
<name>Connections2</name>
<value>7222</value>
<requiresConfiguration>true</requiresConfiguration>
</NameValuePair>
</NameValuePairs>
<NameValuePairs>
<name>Local Variables</name>
<NameValuePair>
<name>Connections3</name>
<value>8222</value>
<requiresConfiguration>true</requiresConfiguration>
</NameValuePair>
<NameValuePair>
<name>Connections3</name>
<value>8222</value>
<requiresConfiguration>true</requiresConfiguration>
</NameValuePair>
</NameValuePairs>
</DeploymentDescriptors>
Java Code
File fDestFile = new File("myfile.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document oDoc3 = dBuilder.parse(fDestFile);
NodeList oDestFlowList = oDoc3.getElementsByTagName("NameValuePairs");
for (int m = 0; m < oDestFlowList.getLength(); m++) {
NodeList oDestchildList = oDestFlowList.item(m).getChildNodes();
for (int n = 0; n < oDestchildList.getLength(); n++) {
Node oDestchildNode = oDestchildList.item(n);
if ("name".equals(oDestchildNode.getNodeName())) {
//oDestchildNode.getParentNode().removeChild(oDestchildNode); //Not Working
//oDoc3.getDocumentElement().removeChild(oDestchildNode); //Not Working
}
}
}
}

You need create a separate reference from the parent node as an Element so that you aren't referencing the node that you are removing:
File fDestFile = new File("src/myfile.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = null;
try {
dBuilder = dbFactory.newDocumentBuilder();
Document oDoc3 = null;
oDoc3 = dBuilder.parse(fDestFile);
NodeList oDestFlowList = oDoc3.getElementsByTagName("NameValuePairs");
// Loop through all 'NameValuePairs'
for (int m = oDestFlowList.getLength()-1; m >=0 ; m--) {
NodeList oDestchildList = oDestFlowList.item(m).getChildNodes();
// Loop through children of 'NameValuePairs'
for (int n = oDestchildList.getLength()-1; n >=0 ; n--) {
// Remove children if they are of the type 'name'
if(oDestchildList.item(n).getNodeName().equals("name")){
oDestFlowList.item(m).removeChild(oDestchildList.item(n));
// For debugging
System.out.println(oDestchildList.item(n).getNodeName());
}
}
}
Source source = new DOMSource(oDoc3);
Result result = new StreamResult(fDestFile);
Transformer transformer = null;
transformer = TransformerFactory.newInstance().newTransformer();
// Transform your XML document (i.e. save changes to file)
transformer.transform(source, result);
} catch (Exception e) {
// Catch the exception here
e.printStackTrace();
}
}
If you are still having issues, then I would think that it is an issue with the node types. This was working for me before I put the check in for 'oDestchildNode.getNodeType()' but I would look at what type of node you are returning and go from there.

Here is the final piece of code that finally worked
public static void main(String[] args) {
File fXmlSubFile = new File("Sub.xml");
File fXmlOriginalFile = new File("Original.xml");
File fDestFile = new File("myfile.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder;
FileChannel source = null;
FileChannel destination = null;
XPath xPath = XPathFactory.newInstance().newXPath();
try{
if (!fDestFile.exists()) {
fDestFile.createNewFile();
}
source = new FileInputStream(fXmlOriginalFile).getChannel();
destination = new FileOutputStream(fDestFile).getChannel();
if (destination != null && source != null) {
destination.transferFrom(source, 0, source.size());
}
if (source != null) {
source.close();
}
if (destination != null) {
destination.close();
}
dBuilder = dbFactory.newDocumentBuilder();
Document oSubDoc = dBuilder.parse(fXmlSubFile);
Document oDestDoc = dBuilder.parse(fDestFile);
oSubDoc.getDocumentElement().normalize();
oDestDoc.getDocumentElement().normalize();
String sDestExpression = "/DeploymentDescriptors/NameValuePairs";
String sSubExpression = "/NameValuePairs";
NodeList nodeDestList = (NodeList) xPath.compile(sDestExpression).evaluate(oDestDoc, XPathConstants.NODESET);
NodeList nodeSubList = (NodeList) xPath.compile(sSubExpression).evaluate(oSubDoc, XPathConstants.NODESET);
for (int i = nodeDestList.getLength()-1; i >=0 ; i--) {
Node oDestNode = nodeDestList.item(i);
if (oDestNode.getNodeType() == Node.ELEMENT_NODE) {
Element oDestElement = (Element) oDestNode;
for (int j =0; j<nodeSubList.getLength(); j++) {
Node oSubNode = nodeSubList.item(j);
if (oSubNode.getNodeType() == Node.ELEMENT_NODE) {
Element oSubElement = (Element) oSubNode;
if(oDestElement.getElementsByTagName("name").item(0).getTextContent().equals(oSubElement.getElementsByTagName("name").item(0).getTextContent())){
oDestNode.getParentNode().removeChild(oDestNode);
}
}
}
}
}
Source src = new DOMSource(oDestDoc);
Result result = new StreamResult(fDestFile);
Transformer transformer = null;
transformer = TransformerFactory.newInstance().newTransformer();
// Transform your XML document (i.e. save changes to file)
transformer.transform(src, result);
}catch(Exception ex){
System.out.println("error:"+ex.getMessage());
ex.printStackTrace();
}
}

Related

Read xml is not giving correct value

I am trying to get the value of orderCode
public class ReadXml {
static Map<String, String> map = new HashMap<>();
static List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>();
public List<HashMap<String, String>> readxml() throws ParserConfigurationException, SAXException, IOException{
File file = new File(
"./resources/XMLFile/test.xml");
// Make an instance of the DocumentBuilderFactory
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document dom = db.parse(file);
dom.getDocumentElement().normalize();
dom.getDocumentElement().getNodeName();
if (dom.hasChildNodes()) {
getNote(dom.getChildNodes()); // now re run
}
return list;
}
private static List<HashMap<String, String>> getNote(NodeList nodeList) {
Node node =null;
for (int count = 0; count < nodeList.getLength(); count++) {
HashMap<String, String> data = new HashMap<>();
Node tempNode = nodeList.item(count);
// make sure it's element node.
if (tempNode.getNodeType() == Node.ELEMENT_NODE) {
if (tempNode.hasAttributes()) {
//get attributes names and values
NamedNodeMap nodeMap = tempNode.getAttributes();
for (int i = 0; i < nodeMap.getLength(); i++) {
node = nodeMap.item(i);
node.getNodeName(); //
node.getNodeValue();
}
}
}
if (tempNode.hasChildNodes()) {
// loop again if has child nodes
getNote(tempNode.getChildNodes());
}
data.put(tempNode.getNodeName(), tempNode.getTextContent());
list.add(data);
}
return list;
}
}
Xml File is below:
<submit> <shortCode>NTT</shortCode>
<order orderCode="TEST/TEST192/2018SEP30/095552">
<description>RegressionTesting</description>
<amount currencyCode="abc"/>
debitCreditIndicator="test" exponent="2" value="123"/>
My problem is , it is not giving the value of OrderCode.
One word, xPath
So, fixing your XML to look like...
<submit>
<shortCode>NTT</shortCode>
<order orderCode="TEST/TEST192/2018SEP30/095552">
<description>RegressionTesting</description>
<amount currencyCode="abc"/>
</order>
</submit>
And using...
try {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
Document doc = factory.newDocumentBuilder().parse(new File("Sample.xml"));
XPathFactory xFactory = XPathFactory.newInstance();
XPath xPath = xFactory.newXPath();
XPathExpression exp = xPath.compile("/submit/order");
Node node = (Node) exp.evaluate(doc.getFirstChild(), XPathConstants.NODE);
if (node != null) {
Node value = node.getAttributes().getNamedItem("orderCode");
System.out.println(value.getTextContent());
}
} catch (Exception ex) {
ex.printStackTrace();
}
Which will print...
TEST/TEST192/2018SEP30/095552
or we can go straight to the attribute itself...
try {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
Document doc = factory.newDocumentBuilder().parse(new File("Sample.xml"));
XPathFactory xFactory = XPathFactory.newInstance();
XPath xPath = xFactory.newXPath();
XPathExpression exp = xPath.compile("/submit/order/#orderCode");
String value = (String) exp.evaluate(doc.getFirstChild(), XPathConstants.STRING);
System.out.println(value);
} catch (Exception ex) {
ex.printStackTrace();
}
Which will print...
TEST/TEST192/2018SEP30/095552
I would also consider having a look at Java API for XML Processing (JAXP) for more details

Parse Xml returns only 1 item

I want to get the File nodes of this xml document, can anyone help me with archive this issue?
I have this xml document:
<?xml version="1.0" encoding="UTF-8"?>
<Replies>
<FileList>
<File>cip13_test.rts</File>
<File>databar_lmt.rts</File>
<File>Test3.rts</File>
<File>databar2_lmt.rts</File>
<File>databar5_lmt.rts</File>
</FileList>
</Replies>
and I need to get all File-items from this.
I have this code but I get only cip13_test.rtx.
public static String GetFileList(String fileresponse) {
String xml = fileresponse;
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = null;
InputSource is = new InputSource();
String textToShow = "";
StringBuilder resultsofList = new StringBuilder();
try {
db = dbf.newDocumentBuilder();
is.setCharacterStream(new StringReader(xml));
try {
Document doc = db.parse(is);
NodeList replies = doc.getElementsByTagName("Replies");
for (int i = 0; i < replies.getLength(); i++) {
Element element = (Element) replies.item(i);
NodeList inkstatus = element.getElementsByTagName("FileList");
for (int i2 = 0; i2 < inkstatus.getLength(); i2++) {
Element element2 = (Element) inkstatus.item(i2);
NodeList inklevel = element2.getElementsByTagName("File");
for (int i4 = 0; i4 < inklevel.getLength(); i4++) {
Element element4 = (Element) inklevel.item(i4);
Element line = (Element) inklevel.item(0);
if (line == null) {
inklevel = element4.getElementsByTagName("File");
line = (Element) inklevel.item(0);
}
textToShow = getCharacterDataFromElement(line);
resultsofList.append(textToShow+",");
}
}
}
} catch (SAXException e) {
// handle SAXException
} catch (IOException e) {
// handle IOException
}
} catch (ParserConfigurationException e1) {
// handle ParserConfigurationException
}
return String.valueOf(resultsofList);
}
This line is wrong:
Element line = (Element) inklevel.item(0);
It should be
Element line = (Element) inklevel.item(i4);

Java + reading data from XML file

What's wrong in this code? It gives me null everytime. I have no idea how to repair it, because in ordinary Java Application it works.
#WebMethod(operationName = "getColor")
public String getColor(#WebParam(name = "regNr") String regNr) {
String kolor=null;
try {
File fXmlFile = new File("/base.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(fXmlFile);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("person");
for (int temp = 0; temp < nList.getLength(); temp++) {
Node nNode = nList.item(temp);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element element = (Element) nNode;
String id = ""+ getValue("id",element);
if (regNr.equals(id)) {
color = element.getElementsByTagName("color").item(0).getTextContent();
return color;
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return color;
}
I think (not sure because I don't know at which point it gives you null) you have to remove the / form the file name to become only base.xml

getNodeValue returnining null?

Hi I am trying to parse and XML file from an url, my NodeList contains values but getNodeValue for each node returns null. Can anybody help me?
This is my method where I parse the xml.
public ArrayList xmloku(String url) {
ArrayList xmllistesi = new ArrayList();
try {
URL xmlyolu = new URL(url);
DocumentBuilderFactory dFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder dBuilder = dFactory.newDocumentBuilder();
Document document = dBuilder.parse(new InputSource(xmlyolu
.openStream()));
document.getDocumentElement().normalize();
NodeList nodeListCountry = document
.getElementsByTagName("karikatur");
for (int i = konum; i < nodeListCountry.getLength(); i++) {
Node node = nodeListCountry.item(i);
Element elementMain = (Element) node;
xmllistesi.add(elementMain.getNodeValue());
}
Instead of getNodeValue() try using getTextContent()
for (int i = konum; i < nodeListCountry.getLength(); i++) {
Node node = nodeListCountry.item(i);
Element elementMain = (Element) node;
xmllistesi.add(elementMain.getTextContent());
}

Deleting XML element in Java

I have an XML:
<?xml version="1.0" encoding="UTF-8"?>
<songs>
<song>
<title>Gracious</title>
<artist>Ben Howard</artist>
<genre>Singer/Songwriter</genre>
</song>
<song>
<title>Only Love</title>
<artist>Ben Howard</artist>
<genre>Singer/Songwriter</genre>
</song>
<song>
<title>Bad Blood</title>
<artist>Bastille</artist>
<genre>N/A</genre>
</song>
<song>
<title>Keep Your Head Up</title>
<artist>Ben Howard</artist>
<genre>Singer/Songwriter</genre>
</song>
<song>
<title>Intro</title>
<artist>Alt-J</artist>
<genre>Alternative</genre>
</song>
</songs>
and my Java code is:
public static void deleteSong(Song song) {
String songTitle = song.getTitle();
String songArtist = song.getArtist();
String songGenre = song.getGenre();
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
File file = new File("songs.xml");
Document doc = db.parse(file);
NodeList songList = doc.getElementsByTagName("song");
if (songList != null && songList.getLength() > 0) {
for (int i = 0; i < songList.getLength(); i++) {
Node node = songList.item(i);
Element e = (Element) node;
NodeList nodeList = e.getElementsByTagName("title");
String title = nodeList.item(0).getChildNodes().item(0)
.getNodeValue();
nodeList = e.getElementsByTagName("artist");
String artist = nodeList.item(0).getChildNodes().item(0)
.getNodeValue();
nodeList = e.getElementsByTagName("genre");
String genre = nodeList.item(0).getChildNodes().item(0)
.getNodeValue();
System.out.println(title + " Title");
System.out.println(songTitle + " SongTitle");
if (title.equals(songTitle)) {
if (artist.equals(songArtist)) {
if (genre.equals(songGenre)) {
doc.getFirstChild().removeChild(node);
}
}
}
}
}
MainDisplay.main(null);
} catch (Exception e) {
System.out.println(e);
}
}
The song to be deleted is passed into the method and then compared to the songs in the xml file. However, if the song matches a song in the xml, it isn't deleted? No exceptions come up.
You need to remove relevant node, in you code you are removing node of firstchild which seems to be incorrect.
And write back your changes to the file.
if (title.equals(songTitle) && artist.equals(songArtist) && genre.equals(songGenre) ) {
node.getParentNode().removeChild(node);
}
// write back to xml file
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource source = new DOMSource(doc);
StreamResult result = new StreamResult(new File(filepath));
transformer.transform(source, result);
From what I see, you are only reading the documents. At some point, you will have to flush the changes back to the XML file.

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