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Reorganize XML using Java DOM - Hierarchy_Request_Error

I have a xml with following scheme structure
<test>
<testcase classname="TestsQuarantine.CreateUsers" name="Administrator"/>
<testcase classname="TestsQuarantine.Login" name="documentMailQuarantine"/>
<testcase classname="TestsClerk.CreateUsers" name="John"/>
</test>
I need to reorganize it to
<test>
<testsuite name="Quarantine">
<testcase classname="TestsQuarantine.CreateUsers" name="Administrator"/>
<testcase classname="TestsQuarantine.Login" name="documentMailQuarantine"/>
</testsuite>
<testsuite name="Clerk">
<testcase classname="TestsClerk.CreateUsers" name="John"/>
</testsuite>
</test>
At this point I'm reading the file to NodeList, iterate through it, create new root and try to switch it with original to achieve the structure that I need but I get following error
HIERARCHY_REQUEST_ERR: An attempt was made to insert a node where it
is not permitted.
happening in line that performs switch of roots and I'm out of ideas why it is so.. Here is my code:
File file = new File(fullPath);
List<Element> clerk = null,
quara = null,
misc = null;
try {
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(file);
NodeList nodes = doc.getElementsByTagName("test");
Element root = doc.getDocumentElement(),
newRoot = doc.createElement("test");
clerk = new ArrayList<Element>();
quara = new ArrayList<Element>();
misc = new ArrayList<Element>();
for(int i=0; i < nodes.getLength(); i++) {
Element node = (Element) nodes.item(i);
if(node.getAttribute("classname").contains("Clerk")) {
clerk.add(node);
} else if(node.getAttribute("classname").contains("Quarantine")) {
quara.add(node);
} else {
misc.add(node);
}
}
if(clerk.isEmpty() == false) {
Element clerkSuite = doc.createElement("testsuite");
clerkSuite.setAttribute("name", "Clerk");
for(Element el : clerk) {
clerkSuite.appendChild(el);
}
newRoot.appendChild(clerkSuite);
}
if(quara.isEmpty() == false) {
Element quaraSuite = doc.createElement("testsuite");
quaraSuite.setAttribute("name", "Quarantine");
for(Element el : quara) {
quaraSuite.appendChild(el);
}
newRoot.appendChild(quaraSuite);
}
if(misc.isEmpty() == false) {
Element miscSuite = doc.createElement("testsuite");
miscSuite.setAttribute("name", "Miscellaneous");
for(Element el : misc) {
miscSuite.appendChild(el);
}
newRoot.appendChild(miscSuite);
}
root.getParentNode().replaceChild(newRoot, root);
DOMSource original = new DOMSource(doc);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
StreamResult overritten = new StreamResult(fullPath);
transformer.transform(original, overritten);
} catch (Exception e) {
e.printStackTrace();
}
What do I have to change to make it work?

Your iteration over testcase nodes is incorrect. I changed that fragment to below one and Your code is working:
Node testNode = doc.getDocumentElement();
NodeList testCases= testNode.getChildNodes();
for(int i=0; i < testCases.getLength(); i++) {
Node n = testCases.item(i);
if (!(n instanceof Text)) {
Element testCase = (Element) n;
if (testCase.getAttribute("classname").contains("Clerk")) {
clerk.add(testCase);
} else if (testCase.getAttribute("classname").contains("Quarantine")) {
quara.add(testCase);
} else {
misc.add(testCase);
}
}
}

Unable to delete a specific node in XML

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();
}
}

javax.xml.transform.Transformer very slow

I am using this code to write a (simple) DOM tree to a string, but on my LG Optimus L3, this takes up to 30 seconds or more. How could I make it faster?
Transformer t = TransformerFactory.newInstance().newTransformer();
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
t.transform(new DOMSource(doc), new StreamResult(writer));
result = writer.getBuffer().toString();

I ended up just writing my own serializer. It certainly doesn't support everything, just tag names, attributes and text content, but it is simple and fast:
void write(Node e, StringWriter w) {
if (e.getNodeType() == Node.ELEMENT_NODE) {
w.write("<"+e.getNodeName());
if (e.hasAttributes()) {
NamedNodeMap attrs = e.getAttributes();
for (int i = 0; i < attrs.getLength(); i++) {
w.write(" "+attrs.item(i).getNodeName()+"=\""+
attrs.item(i).getNodeValue()+"\"");
}
}
w.write(">");
if (e.hasChildNodes()) {
NodeList children = e.getChildNodes();
for (int i = 0; i < children.getLength(); i++) {
write(children.item(i), w);
}
}
w.write("</"+e.getNodeName()+">");
}
if (e.getNodeType() == Node.TEXT_NODE) {
w.write(e.getTextContent());
}
}
You use it with a Document like this:
StringWriter writer = new StringWriter();
String result;
write(doc.getDocumentElement(), writer);
result = writer.getBuffer().toString();

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.

getting null pointer exception exporting data from database to xml

Im trying this java code to export data from database using sql query, But getting a null pointer exception. getting no clue to remove it . Im getting this exception at the line in Bold font.
try {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.newDocument();
Element results = doc.createElement("Results");
doc.appendChild(results);
Class.forName("oracle.jdbc.OracleDriver");
Connection con = DriverManager
.getConnection("jdbc:oracle:thin:#localhost:1521:XE", "hr", "hr");
ResultSet rs = con.createStatement().executeQuery("select * from departments");
ResultSetMetaData rsmd = rs.getMetaData();
int colCount = rsmd.getColumnCount();
while (rs.next()) {
Element row = doc.createElement("Row");
results.appendChild(row);
for (int i = 1; i <= colCount; i++) {
String columnName = rsmd.getColumnName(i);
Object value = rs.getObject(i);
Element node = doc.createElement(columnName);
row.appendChild(node);
**node.appendChild(doc.createTextNode(value.toString()));**
}
}
DOMSource domSource = new DOMSource(doc);
TransformerFactory tf = TransformerFactory.newInstance();
Transformer transformer = tf.newTransformer();
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
transformer.setOutputProperty(OutputKeys.ENCODING, "ISO-8859-1");
StringWriter sw = new StringWriter();
StreamResult sr = new StreamResult(sw);
transformer.transform(domSource, sr);
System.out.println(sw.toString());
con.close();
rs.close();
} catch (Exception e) {
e.printStackTrace();
}
Stack trace :
java.lang.NullPointerException
at org.ProjectXML.ui.DataBaseToXML.main(DataBaseToXML.java:61)
Any ideas?

The trick is to add this simple piece of code inside the while loop:
if (value != null)
node.appendChild(doc.createTextNode(value.toString()));
else
node.appendChild(doc.createTextNode(""));
row.appendChild(node);
Full code:
public static String ConvertToXML1(ResultSet rs, String view)
throws Exception {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.newDocument();
Element results = doc.createElement(view);
doc.appendChild(results);
ResultSetMetaData rsmd = rs.getMetaData();
int colCount = rsmd.getColumnCount();
while (rs.next()) {
Element row = doc.createElement("Row");
results.appendChild(row);
for (int i = 1; i <= colCount; i++) {
String columnName = rsmd.getColumnName(i);
Object value = rs.getObject(i);
Element node = doc.createElement(columnName);
// The added code is here
if (value != null)
node.appendChild(doc.createTextNode(value.toString()));
else
node.appendChild(doc.createTextNode(""));
row.appendChild(node);
}
}
DOMSource domSource = new DOMSource(doc);
TransformerFactory tf = TransformerFactory.newInstance();
Transformer transformer = tf.newTransformer();
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
transformer.setOutputProperty(OutputKeys.ENCODING, "ISO-8859-1");
StringWriter sw = new StringWriter();
StreamResult sr = new StreamResult(sw);
transformer.transform(domSource, sr);
return sw.toString();
}