Develop Reference

Java get tag name of a Node

I need to read a small xml file and validate it's content against a hardcoded HashMap with key= tag and value= text inside tag.
I can not get the tag name of the Node.
If I convert the Node to Element I get a cast exception.
I am reading using the DOOM classes:
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(xmlFile);
NodeList list = doc.getElementsByTagName("MergeOptions");
if (list.getLength() == 0)
{
//throw
}
NodeList config = list.item(0).getChildNodes();
for (int i = 0; i <= config.getLength() - 1; i++)
{
Node setting = config.item(i);
String nodeName = setting.getNodeValue();
String value = setting.getTextContent();
if (defaultMergeOptions.containsKey(nodeName) == false)
{
//throw
}
if (defaultMergeOptions.get(nodeName).equals(value))
{
//throw
}
Xml file:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<MergeOptions>
<sometagName>false</sometagName>
</MergeOptions>

I am helping you with the following code structure. Once you see the tag name and the value, you can apply the logic to compare from HashMap key or value.
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class Test1 {
public static void main(String[] args) throws Exception {
String xmlFile = "test.xml";
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(xmlFile);
Element root = doc.getDocumentElement();
System.out.println(root.getNodeName());
NodeList list = root.getChildNodes();
for (int i = 0; i < list.getLength(); i++) {
Node node = list.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE)
{
System.out.println(node.getNodeName() + " : " + node.getTextContent());
}
}
}
}

I have tried to run your code, it works fine, no class cast exceptions.
Note how I used the element in the for loop the get the name, value or the existsnce of a possible children.
final String xml = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" +
"<MergeOptions>\n<sometagName>false</sometagName>\n</MergeOptions>";
final InputStream xsmlStream = new ByteArrayInputStream(xml.getBytes());
final DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
final DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
final Document doc = dBuilder.parse(xsmlStream);
final NodeList nodes = doc.getElementsByTagName("MergeOptions");
for (int i = 0; i < nodes.getLength(); i++) {
final Element element = (Element) nodes.item(i);
System.out.println(element.hasChildNodes());
System.out.println(element.getNodeValue());
System.out.println(element.getTagName());
}
Using hash map is with node names as keys is a bit tricky, 'cause if your XML file have multiple node names with same names and different values, the HashMap will only store only one unique keys thus validate only one of the same name nodes. The other same name nodes but with different values will be not valid.

Well I did something diffrent.
Seems to work:
IntegrationTest.getInstance().getLogger().log(Level.INFO, "Reading merge-que file: " + xmlFile.getAbsolutePath());
try
{
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(xmlFile);
for (Entry<String, String> entry : defaultMergeOptions.entrySet())
{
String tagName = entry.getKey();
NodeList list = doc.getElementsByTagName(tagName);
if (list.getLength() != 1)
{
IntegrationTest.getInstance().getLogger().log(Level.SEVERE, TestResult.FAIL, "Merge option [{0}] has invalid content. Tag [{1}] missing or to many",
new Object[] { xmlFile.getName(), tagName });
result = TestResult.FAIL;
continue;
}
if (!defaultMergeOptions.get(tagName).equals(list.item(0).getTextContent()))
{
IntegrationTest.getInstance().getLogger().log(Level.WARNING, TestResult.FAIL, "Merge option [{0}] has diffrent content for tag [{1}].",
new Object[] { xmlFile.getCanonicalPath(), tagName });
result = TestResult.FAIL;
}
}
}
catch (Exception e)
{
IntegrationTest.getInstance().getLogger().log(Level.SEVERE, SBUtil.stackTraceToString(e.getStackTrace()));
throw new IntegrationTestException(e);
}
}

How get XML value from Unziped file

I need to get value like "Symbol" ect. from xml file and send to list.
For now my code looks like this:
Scanner sc = null;
byte[] buff = new byte[1 << 13];
List<String> question2 = new ArrayList<String>();
question2 = <MetodToGetFile>(sc,fileListQ);
for ( String strLista : question2){
ByteArrayInputStream in = new ByteArrayInputStream(strLista.getBytes());
try(InputStream reader = Base64.getMimeDecoder().wrap(in)){
try (GZIPInputStream gis = new GZIPInputStream(reader)) {
try (ByteArrayOutputStream out = new ByteArrayOutputStream()){
int readGis = 0;
while ((readGis = gis.read(buff)) > 0)
out.write(buff, 0, readGis);
byte[] buffer = out.toByteArray();
String s2 = new String(buffer);
}
}
}
}
}
I want to know how can i contunue this and takevalue "xxx" and "zzzz" to put to another list, because i need to compere some value.
XML looks like this:
<?xml version="1.0" encoding="utf-8"?>
<Name Name="some value">
<Group Names="some value">
<Package Guid="{7777-7777-7777-7777-7777}">
<Attribute Typ="" Name="Symbol">xxx</Attribute>
<Attribute Type="" Name="Surname">xxx</Attribute>
<Attribute Type="Address" Name="Name">zzzz</Attribute>
<Attribute Type="Address" Name="Country">zzzz</Attribute>
</Package>
EDIT: Hello i hope that my solution will be usefull for someone :)
try{
//Get is(inputSource with xml in s2(xml string value from stream)
InputSource is = new InputSource(new StringReader(s2));
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(is);
XPathFactory xpf = XPathFactory.newInstance();
XPath xpath = xpf.newXPath();
//Get "some value" from attribut Name
String name= (String) xpath.evaluate("/Name/#Name", doc, XPathConstants.STRING);
//Get "guid" from attribute guid
String guid= (String) xpath.evaluate("/Name/Group/Package/#Guid", doc, XPathConstants.STRING);
//Get element xxx by tag value Symbol
String symbol= xpath.evaluate("/Name/Group/Package/Attribute[#Name=\"Symbol\"]", doc.getDocumentElement());
System.out.println(name);
System.out.println(guid);
System.out.println(symbol);
}catch(Exception e){
e.printStackTrace();
}
I would be happy if i will help someone by my code :)

Add a method like this to retrieve all of the elements that match a given Path expression:
public List<Node> getNodes(Node sourceNode, String xpathExpresion) throws XPathExpressionException {
// You could cache/reuse xpath for better performance
XPath xpath = XPathFactory.newInstance().newXPath();
NodeList nodes = (NodeList) xpath.evaluate(xpathExpresion,sourceNode,XPathConstants.NODESET);
ArrayList<Node> list = new ArrayList<Node>();
for(int i = 0; i < nodes.getLength(); i++) {
Node node = nodes.item(i);
list.add(node);
}
return list;
}
Add another method to build a Document from an XML input:
public Document buildDoc(InputStream is) throws Exception {
DocumentBuilderFactory fact = DocumentBuilderFactory.newInstance();
DocumentBuilder parser = fact.newDocumentBuilder();
Document newDoc = parser.parse(is);
newDoc.normalize();
is.close();
return newDoc;
}
And then put it all together:
InputSource is = new InputSource(new StringReader("... your XML string here"));
Document doc = buildDoc(is);
List<Node> nodes = getNodes(doc, "/Name/Group/Package/Attribute");
for (Node node: nodes) {
// for the text body of an element, first get its nested Text child
Text text = node.getChildNodes().item(0);
// Then ask that Text child for it's value
String content = node.getNodeValue();
}
I hope I copied and pasted this correctly. I pulled this from a working class in an open source project of mine and cleaned it up a bit to answer your specific question.

Read inside a Tag using XPath Java

Hye I am new to read XML File using Java my problem is that I have been trying to read an xml and between a specific tag I want to get the required data I am using XPath and my query is:
String expression = "/ADOXML/MODELS/MODEL/MODELATTRIBUTES/ATTRIBUTE[#type='STRING']";
It works fine and my specific Tag to read from is:
<ATTRIBUTE name="Description" type="STRING"> SOME TEXT </ATTRIBUTE>
But I want to read the data inside only these types of Tags so that my output should be:
SOME TEXT
inside the tag!
can somebody help me how can I do this Please I am new to xml reading! Trying my best as:
String expression = "/ADOXML/MODELS/MODEL/MODELATTRIBUTES/ATTRIBUTE[#name='Description' and ./type/text()='STRING']";
But it wont give me any output!
thanks in advance
My Code:
DocumentBuilderFactory builderFactory =
DocumentBuilderFactory.newInstance();
DocumentBuilder builder = null;
try {
builder = builderFactory.newDocumentBuilder();
org.w3c.dom.Document document = builder.parse(
new FileInputStream("c:\\y.xml"));
XPath xPath = XPathFactory.newInstance().newXPath();
String expression = "/ADOXML/MODELS/MODEL/MODELATTRIBUTES/ATTRIBUTE[#name='Description'and #type='STRING']";
System.out.println(expression);
NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(document, XPathConstants.NODESET);
for (int i = 0; i < nodeList.getLength(); i++) {
System.out.println(nodeList.item(i).getFirstChild().getNodeValue());
}
} catch (ParserConfigurationException | SAXException | IOException e) {
System.out.print(e);
}
There is a problem with my code cant figure out what!

This code works fine for me with the changed XPath to:
"/ADOXML/MODELS/MODEL/MODELATTRIBUTES/ATTRIBUTE[#name='Description'][#type='STRING']":
private static final String EXAMPLE_XML =
"<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
"<ADOXML adoversion=\"Version 5.1\" username=\"kvarga\" database=\"adonisdb\" time=\"08:55\" date=\"30.11.2013\" version=\"3.1\">" +
"<MODELS>" +
"<MODEL version=\"\" applib=\"ADONIS BPMS BP Library 5.1\" libtype=\"bp\" modeltype=\"Business process model\" name=\"Product development\" id=\"mod.25602\">" +
"<MODELATTRIBUTES>" +
"<ATTRIBUTE name=\"Version number\" type=\"STRING\"> </ATTRIBUTE>" +
"<ATTRIBUTE name=\"Author\" type=\"STRING\">kvarga</ATTRIBUTE>" +
"<ATTRIBUTE name=\"Description\" type=\"STRING\">I WANT THIS PARA 2</ATTRIBUTE>" +
"</MODELATTRIBUTES>" +
"</MODEL>" +
"</MODELS>" +
"</ADOXML>";
public static void main(String[] args) {
DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = null;
try {
builder = builderFactory.newDocumentBuilder();
Document document = builder.parse(new ByteArrayInputStream(EXAMPLE_XML.getBytes()));
XPath xPath = XPathFactory.newInstance().newXPath();
String expression = "/ADOXML/MODELS/MODEL/MODELATTRIBUTES/ATTRIBUTE[#name='Description'][#type='STRING']";
NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(document, XPathConstants.NODESET);
for (int i = 0; i < nodeList.getLength(); i++) {
System.out.println("###" + nodeList.item(i).getFirstChild().getNodeValue() + "###");
}
} catch (Exception e) {
System.out.print(e);
}
}
OUTPUT:
###I WANT THIS PARA 2###

The mentioned code works fine.
You can try other way also to get the text node -
String expression = "/ADOXML/MODELS/MODEL/MODELATTRIBUTES/ATTRIBUTE/text()";
NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(document, XPathConstants.NODESET);
System.out.println(nodeList.item(0).getNodeValue());

getNodeValue() returns some random string

I have an android project with file res/raw/lvl.xml
<?xml version="1.0" encoding="utf-8"?>
<Level>
<dimensions>
<a>5</a>
<b>5</b>
</dimensions>
.
.
.
</Level>
My java code is following
InputStream input = this.getResources().openRawResource(R.raw.lvl);
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = buider.parse(input);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("dimensions");
Node node = nList.item(0);
int a = Integer.parseInt(node.getFirstChild().getNodeValue().trim());
The last line throws parsing exception, node.getNodeValue().trim() is "\t\t\n\t".

You're looking at the <dimensions> tag, not at a and b. Look:
NodeList nList = doc.getElementsByTagName("dimensions");
Node node = nList.item(0);
int a = Integer.parseInt(node.getNodeValue().trim());
You're getting the first (index 0) element of name dimensions. Not its children.
The value you see (\t\t\n\t) is what's left of dimensions' contents after children nodes are removed.

Could not understand what exactly you are trying to do ...but .. you can refer below if that helps
public class Parsing {
public static void main(String[] args) throws ParserConfigurationException, SAXException, IOException {
Parsing parse = new Parsing();
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(new File("x.xml"));
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("dimensions");
Node node = nList.item(0);
for (Node childNode = node.getFirstChild();
childNode != null;) {
//do something
System.out.println(childNode.getNodeName());
System.out.println(childNode.getTextContent());
Node nextChild = childNode.getNextSibling();
childNode = nextChild;
}
}
}

Need help extracting XML element values and depositing them into a map or other type of collection in Java

The below code prints the element contents of my XML file, however, for the life of me I have been unsuccessful at extracting the element values and putting them in a map or other type of array or list. Any help would be greatly appreciated!!!!
public class client
{
public static void main(String[] args )
{
int length = 0;
String [] array;
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
try {
//Using factory get an instance of document builder
DocumentBuilder builder = factory.newDocumentBuilder();
//create the document by parsing the actual file
Document doc = builder.parse(new File ("server.xml"));
//creat an XPath to be used in the extraction of the nodes
XPathFactory xPFactory = XPathFactory.newInstance();
XPath path = xPFactory.newXPath();
//Extract ports
XPathExpression portExpr
= path.compile("//configuration/hostInfo/port");
//Extract hosts
XPathExpression hostExpr
= path.compile("//configuration/hostInfo/host");
Object pResult = portExpr.evaluate(doc, XPathConstants.NODESET);
Object hResult = hostExpr.evaluate(doc, XPathConstants.NODESET);
NodeList pNodes = (NodeList) pResult;
NodeList hNodes = (NodeList) hResult;
array = new String [(pNodes.getLength())*2];
array = populateArray(array, pNodes, hNodes);
for (int k = 0; k < array.length; k++)
System.out.println( k+ "="+ array[k]);
}catch (Exception e) {
e.printStackTrace();
}
}
public static String[] populateArray (String array[], NodeList pNodes, NodeList hNodes){
array[0]=pNodes.item(0).getTextContent();
array[1]=hNodes.item(1).getTextContent();
for (int i = 1; i < pNodes.getLength(); i++){
array[2*i]= pNodes.item(i).getTextContent();
array[(2*i)+1]= hNodes.item(i).getTextContent();
}
return array;
}
}
XML FILE
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<hostInfo>
<port>8189</port>
<host>localhost</host>
</hostInfo>
<hostInfo>
<port>8190</port>
<host>localhost</host>
</hostInfo>
<hostInfo>
<port>8191</port>
<host>localhost</host>
</hostInfo>
</configuration>

You can do path.compile that will return a XPathExpression object. Then you can call evaluate to get an array of NodeList.
Take a look at http://www.ibm.com/developerworks/library/x-javaxpathapi.html and http://download.oracle.com/javase/1.5.0/docs/api/javax/xml/xpath/package-summary.html .