Develop Reference

Edit an xml file element using dom

Please tell me what I'm doing wrong.
I work with javafx and by clicking on the button, when the listview element is selected, I pass an object of the Country class to the editing method, but the xml file is not being edited, what is the problem?
I attached an xml file, a broken edit function and a working delete function. I think it's about the setContext I'm calling? But I'm not sure
Xml file:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<CountrysList lastId="3">
<Country id="1">
<name>Russia</name>
<continent>Eurasia</continent>
<area>17125191</area>
<population>145557576</population>
<capital>Moscow</capital>
</Country>
<Country id="2">
<name>Russia</name>
<continent>Eurasia</continent>
<area>17125191</area>
<population>145557576</population>
<capital>Moscow</capital>
</Country>
<Country id="3">
<name>Russia</name>
<continent>Eurasia</continent>
<area>17125191</area>
<population>145557576</population>
<capital>Moscow</capital>
</Country>
Element search function:
public Element findCountry(Document document, int id) {
NodeList countries = document.getElementsByTagName("Country");
Element currentCountry = null;
int i = 0;
while(i < countries.getLength() && currentCountry == null){
Node node = countries.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE){
Element element = (Element) node;
if(String.valueOf(id).equals(element.getAttribute("id"))){
currentCountry = element;
}
}
i++;
}
return currentCountry;
}
Broken editing function:
public void redact(Country country) throws ParserConfigurationException, IOException, SAXException, TransformerException {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document document = docBuilder.parse(path);
Element currentCountry = findCountry(document, country.getId());
if(currentCountry != null){
NodeList children = currentCountry.getChildNodes();
for (int j=0; j < children.getLength(); j++){
Node node = children.item(j);
if (node.getNodeType() == Node.ELEMENT_NODE) {
Element element = (Element) node;
switch (element.getTagName()){
case "name":
element.setTextContent(country.getName());
break;
case "continent":
element.setTextContent(country.getContinent());
break;
case "area":
element.setTextContent(String.valueOf(country.getArea()));
break;
case "population":
element.setTextContent(String.valueOf(country.getPopulation()));
break;
case "capital":
element.setTextContent(country.getCapital());
break;
}
}
}
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.transform(new DOMSource(document), new StreamResult(path));
}
}
Working deletion function:
public void delete(Country country) throws ParserConfigurationException, IOException, SAXException, TransformerException {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document document = docBuilder.parse(path);
Element rootElement = document.getDocumentElement();
Element currentCountry = findCountry(document, country.getId());
if(currentCountry != null){
rootElement.removeChild(currentCountry);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.transform(new DOMSource(document), new StreamResult(path));
}
}

I found the mistake.Everything is really like that, I forgot to create a new instance of the class with the changed fields and passed it with the previous ones, so everything worked

Get second row xml using first rows text value java

public void loadSettings() {
try {
File inputFile = new File("data.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(inputFile);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("Setting");
for (int temp = 0; temp < nList.getLength(); temp++) {
Node nNode = nList.item(temp);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element eElement = (Element) nList.item(temp);
NodeList VariableName = eElement.getElementsByTagName("VariableName");
NodeList VariableValue = eElement.getElementsByTagName("VariableValue");
System.out.println(VariableName.item(0).getTextContent());
if (VariableName.item(0).hasChildNodes()) {
}
// txtBookmarkUrl.setText(bookMarkUrl);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
I want to make a function that gets second part of the xml in settings elements. I want the function to return a result so that i can assign it to textfield default value when the swing GUI starts. The function should take let's say 'isDecaptcher' variable name and return '0' VariableValue.
<Bookmark>
<Setting>
<VariableName>isDeathbycaptcha</VariableName>
<VariableValue>0</VariableValue>
</Setting>
<Setting>
<VariableName>isDecaptcher</VariableName>
<VariableValue>0</VariableValue>
</Setting>
<Setting>
<VariableName>isExpertdecoders</VariableName>
<VariableValue>0</VariableValue>
</Setting>
<Setting>
<VariableName>ManualCaptcha</VariableName>
<VariableValue>1</VariableValue>
</Setting>
</Bookmark>

public void loadSettings(String variableName) {
try {
File inputFile = new File("data.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(inputFile);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("Setting");
for (int temp = 0; temp < nList.getLength(); temp++) {
Node nNode = nList.item(temp);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element eElement = (Element) nList.item(temp);
NodeList VariableName = eElement.getElementsByTagName("VariableName");
NodeList VariableValue = eElement.getElementsByTagName("VariableValue");
if (VariableName.item(0).getTextContent().equalsIgnoreCase(variableName)) {
String txtBookmarkUrlValue = VariableValue.item(0).getLastChild().getTextContent();
System.out.println(txtBookmarkUrlValue);
txtBookmarkUrl.setText(txtBookmarkUrlValue);
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
This works, But if you have more robust answers you can share.

First of all create an Object wich will represent your settings. The case is to reuse it's values in whole app. I assume that you will use it only once at the beginning and settings will not change. Singleton pattern would fit there.
final class Settings{
private static volatile Settings instance = null;
private boolean _isDeathByCaptcha;
private boolean _manualCaptcha;
...
//getters & setters
public boolean isDeathByCaptcha(){
return _isDeathByCaptcha;
}
public void setIsDeathByCaptcha(boolean isDeathByCaptcha){
this._isDeathByCaptcha = isDeathByCaptcha;
}
private Settings(){}
public static Settings getInstance(){
if(instance == null){
synchronized (Settings.class) {
if (instance == null) {
instance = new Settings();
}
}
}
return instance;
}
}
After that you can call Settings.getInstance().isDeathByCaptcha(); to get your value. Of course you need to set it earlier with setter.

How to fetch node in XML using Java?

I want to fetch value of the node ServerVersion
<result>
<response id="27mSTG">
<routing>
<configs>
<linqmap.routing.RoutingServerConfig>
<SERVER_VERSION>1.0.388</SERVER_VERSION>
<PRE_PROCESSING_FILE_LOCATION/>
I have tried:
#Override
public void getProp(String prop) {
try {
final Document document = loadXMLFromString();
document.getElementById(??);
} catch (Exception e) {
e.printStackTrace();
}
}
private Document loadXMLFromString() throws Exception
{
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
InputSource is = new InputSource(new StringReader(xmlString));
return builder.parse(is);
}
But I’m not sure how to get the node’s ID.
Is there any easier way? Maybe even string parsing is enough?

There is no attribute Id defined in your xml element SERVER_VERSION. You can use document.getElementByTagName("SERVER_VERSION") to get the value.
Or use XPath to read the node:
final Document document = loadXMLFromString();
XPathFactory xpathfactory = XPathFactory.newInstance();
XPath xpath = xpathfactory.newXPath();
String xpathExpr="/result/SERVER_VERSION"; // assume result is the root node.
Node node=(Node)xPath.compile(xpathExpr).evaluate(document, XPathConstants.NODE);

How to parse an xml and get the content of specific element

My xml String is
Got message from Queue ==> <?xml version='1.0' encoding='UTF-8'?><soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003
/05/soap-envelope"><soapenv:Body><ns1:PostPublicationResponse xmlns:ns1="http://www.openoandm.org/xml/ISBM/"><ns1:Messag
eID>urn:uuid:7d361fb0-bc54-48bd-bbd1-6e34960ef3f8</ns1:MessageID><ns1:MessageContent><MessageContent xmlns="http://www.o
penoandm.org/xml/ISBM/"><hi>k786</hi></MessageContent></ns1:MessageContent></ns1:PostPublicationResponse></soapenv:Body>
</soapenv:Envelope>
Now i have writtent a function that is trying to get Content of element MessageContent i.e <hi>k786</hi> but i am getting null value always.
My function to parse above xml is:
private String parseQueueMessage(String message)
throws ParserConfigurationException, SAXException, IOException,
XPathExpressionException {
String resultMsg = "";
DocumentBuilderFactory domFactory = DocumentBuilderFactory
.newInstance();
domFactory.setNamespaceAware(true);
DocumentBuilder builder = domFactory.newDocumentBuilder();
Document doc = builder.parse(new InputSource(new java.io.StringReader(
message)));
XPath xpath = XPathFactory.newInstance().newXPath();
// XPath Query for showing all nodes value
xpath.setNamespaceContext(new NamespaceContext() {
#SuppressWarnings("rawtypes")
#Override
public Iterator getPrefixes(String arg0) {
return null;
}
#Override
public String getPrefix(String arg0) {
return null;
}
#Override
public String getNamespaceURI(String arg0) {
if("xmlns:ns1".equals(arg0)) {
return "http://www.openoandm.org/xml/ISBM/";
}
return null;
}
});
XPathExpression expr = xpath.compile("//xmlns:ns1:MessageContent");
Object result = expr.evaluate(doc, XPathConstants.NODESET);
NodeList nodes = (NodeList) result;
for (int i = 0; i < nodes.getLength(); i++) {
System.out.println("The message obtained after parsing : "
+ nodes.item(i).getNodeValue());
resultMsg = nodes.item(i).getNodeValue();
}
return resultMsg;
}
What i have done wrong in here?
Thanks in advance

You need to define the name space URI first before selecting from XPATH. For example, first define the namespace URI as follows on the root;
element.setAttribute("xmlns:ns1", "http://www.openoandm.org/xml/ISBM/");
xpath.compile("//ns1:MessageContent");

//Try something like ...
XmlDocument doc = new XmlDocument();
doc.LoadXml("urn:uuid:7d361fb0-bc54-48bd-bbd1-6e34960ef3f8k786
");
XmlElement elem = (XmlElement) doc.DocumentElement.FirstChild;
Console.Write("{0}:{1} = {2}", elem.Prefix, elem.LocalName, elem.InnerText);
Console.WriteLine("\t namespaceURI=" + elem.NamespaceURI);

Reading List of Node using Xpath

this is my XML file :
<sitemesh>
<mapping path="/editor/tempPage/**" exclude="true"/>
<mapping decorator="/WEB-INF/views/decorators/detailstheme.jsp"
path="/*" exclude="false" />
</sitemesh>
I want list of mapping node with their attribute values.
this should be done using Xpath.
my xpath expression is :
expr = xpath.compile("/sitemesh/mapping");
but i am getting null in nodelist.
this is my code:
Map<String,String> map=new HashMap<String, String>();
// reading xml file
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder;
Document doc = null;
XPathExpression expr = null;
try {
builder = factory.newDocumentBuilder();
// creating input stream
doc = builder.parse(file);
XPathFactory xpf = XPathFactory.newInstance();
XPath xpath = xpf.newXPath();
expr = xpath.compile("//mapping");
} catch (Exception e) {
LOG.error("some exception message", e);
}
//------------------------------------------------------------------------
NodeList attributeElements = null;
try {
attributeElements =(NodeList)expr.evaluate(doc, XPathConstants.NODE);
} catch (XPathExpressionException e) {
LOG.error("some exception message", e);
}
System.out.println("lenght:"+attributeElements.getLength());
for (int i = 0; i < attributeElements.getLength(); i++) {
Node node=attributeElements.item(i);
System.out.println("node:"+node.getNodeValue());
NamedNodeMap attrs = node.getAttributes();
for(i = 0 ; i<attrs.getLength() ; i++) {
Attr attribute = (Attr)attrs.item(i);
System.out.println("Node Attributes : " + attribute.getName()+" = "+attribute.getValue());
}
}
//-------------------------------------------------------------------------
// writing xml file
TransformerFactory transformerFactory = TransformerFactory
.newInstance();
Transformer transformer;
try {
transformer = transformerFactory.newTransformer();
DOMSource source = new DOMSource(doc);
StreamResult result = new StreamResult(file);// creating output
// stream
transformer.transform(source, result);
} catch (Exception e) {
LOG.error("some exception message", e);
}
return map;
i am getting null for attributeElements
i want to show values of path,decorator and exclude on JSP page.But i am unable to get list of node through xpath expression.
I want solution for reading mapping node element in Xpath.

[edit] /sitemesh/mapping also works .
The issue here is that you evaluating the express for XPathConstants.NODE while the nodeList maps to XPathConstants.NODESET. please refer below link.
http://docs.oracle.com/javase/1.5.0/docs/api/javax/xml/xpath/XPathConstants.html#NODESET
Added sample code for illustration purpose only:
public void testXpathExpr(){
String testXML = "<sitemesh><mapping path=\"/editor/tempPage/**\" exclude=\"true\"/><mapping decorator=\"/WEB-INF/views/decorators/detailstheme.jsp\" path=\"/*\" exclude=\"false\" /></sitemesh>";
NodeList nodeList = getNodeList(testXML);
}
private NodeList getNodeList(String xml) throws SAXException, IOException, ParserConfigurationException, XPathExpressionException {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = docFactory.newDocumentBuilder();
document = builder.parse(new ByteArrayInputStream( xml.getBytes() ) );
XPathExpression exprPath = xpath.compile(xpathExpr);
NodeList nodeList = (NodeList) exprPath.evaluate(document, XPathConstants.NODESET);;
return nodeList;
}
Hope this helps!

Your xpath works perfectly for me. Below is the sample code:
public class Parser {
public static void main(String[] args) throws Exception, Exception {
final DocumentBuilderFactory factory = DocumentBuilderFactory
.newInstance();
final DocumentBuilder builder = factory.newDocumentBuilder();
final Document doc = builder.parse("src/sitemesh.xml");
final XPathFactory xPathfactory = XPathFactory.newInstance();
final XPath xpath = xPathfactory.newXPath();
final XPathExpression expr = xpath.compile("/sitemesh/mapping");
Object node = expr.evaluate(doc, XPathConstants.NODE);
System.out.println(node);
}
}
sitemesh.xml contains your sample input.