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java search specific attribut name in the xml file

I wouldlike to search in my xml file all attribut (name) without use element tag node :
xml :
<test 1><test1/>
<test2> <test2/>
<test 3 id="aaa"> </test3>
<test 5> </test5>
<test 6 id="bbb" name="ijof"> </test6>
JAVA :
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse(new File(path));
root = document.getDocumentElement();
String attribut = root.getAttribute("name");
System.out.println(attribut); // Expected ijof

Did you execute your code at least once? I dont't think so. Otherwise you would have surely noticed that your XML cannot be parsed.
There are several flaws in your example XML:
No root element.
Wrong end tags: It should be <test1></test1> and not <test1><test1/>.
Element names must not contain whitespace and start and end tag must match. It should be <test5> </test5> and not <test 5> </test5>
Apart of that you can use XPATH to get all elements with a name attribute.
Here is a complete example with the XML as a string but this should be irrelevant:
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import java.io.IOException;
import java.io.StringReader;
public class FindNameAttribute {
private static final String XML =
"<root>\n" +
" <test1></test1>\n" +
" <test2> </test2>\n" +
" <test3 id=\"aaa\"> </test3>\n" +
" <test4 name=\"4\"/>\n" +
" <test5> </test5>\n" +
" <test6 id=\"bbb\" name=\"ijof\"> </test6>\n" +
" <test7 id=\"bbb\"><child name=\"childname\"/> </test7>\n" +
"</root>\n";
public static void main(String[] args) {
System.out.println(XML);
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = null;
try {
builder = factory.newDocumentBuilder();
StringReader reader = new StringReader(XML);
InputSource source = new InputSource(reader);
Document document = builder.parse(source);
XPath xpath = XPathFactory.newInstance().newXPath();
NodeList nodes = (NodeList) xpath.evaluate("//*[#name]", document, XPathConstants.NODESET);
for(int i = 0; i < nodes.getLength(); i++) {
Element el = (Element) nodes.item(i);
String elementName = el.getTagName();
String nameAttribute = el.getAttribute("name");
System.out.println(String.format("Element name: %s, name attribute: %s", elementName, nameAttribute));
}
} catch (ParserConfigurationException | SAXException | IOException | XPathExpressionException e) {
e.printStackTrace();
}
}
}
This is the output:
<root>
<test1></test1>
<test2> </test2>
<test3 id="aaa"> </test3>
<test4 name="4"/>
<test5> </test5>
<test6 id="bbb" name="ijof"> </test6>
<test7 id="bbb"><child name="childname"/> </test7>
</root>
Element name: test4, name attribute: 4
Element name: test6, name attribute: ijof
Element name: child, name attribute: childname
The relevant XPATH expression is: //*[#name]
//: Looks for every element in the document
*: Placeholder for element name. Each name matches.
*[#name]: The [] denotes the predicate. We only want elements with a name attribute.
#: Means the following name is the name of an attribute. Whithout it would be interpreted as an element name

Trying to parse XML data with Java - Getting error: "The method getNodeType() is undefined for the type NodeList"

I'm just starting out with learning how to process/parse XML data in Java. I'm getting the error, "The method getNodeType() is undefined for the type NodeList" on the line, after my for-loop, that contains:
if (n.getNodeType() == Node.ELEMENT_NODE){
The type of error seems like I forgot to import something, but I believe I got everything. I am using an XML example from microsoft, in the following link:
http://msdn.microsoft.com/en-us/library/ms762271(v=vs.85).aspx
Thanks in advance.
import java.io.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Element;
public class Files {
public static void main (String [] args) throws IOException, ParserConfigurationException{
String address = "/home/leo/workspace/Test/Files/src/file.xml";
File xmlFile = new File(address);
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = factory.newDocumentBuilder();
Document doc = dBuilder.parse(xmlFile);
doc.getDocumentElement().normalize();
System.out.println(doc.getDocumentElement().getNodeName());
NodeList n = doc.getElementsByTagName("book id");
for (int temp = 0; temp < n.getLength(); temp++){
System.out.println(n.item(temp));
if (n.getNodeType() == Node.ELEMENT_NODE){
Element e = (Element) n;
System.out.println("author : " + e.getAttribute("author"));
System.out.println("title : " + e.getAttribute("title") );
System.out.println("genre : " + e.getAttribute("genre"));
System.out.println("price : " + e.getAttribute("price"));
System.out.println("publish_date : " + e.getAttribute("publish_date"));
System.out.println("description : " + e.getAttribute("description"));
}
}
}
}

You are calling getNodeType() on a NodeList object (n).
You need to call this function on a Node object. Example :
n.item(temp).getNodeType();

getElementsByTagName searching down all levels of XML nodes

I have this XML file:
<root>
<node1>
<name>A</name>
<node2>
<name>B</name>
<node3>
<name>C</name>
<number>001</number>
</node3>
</node2>
</node1>
</root>
I am parsing the file, to get the name for each node, and the corresponding number if existing.
I use:
String number = eElement.getElementsByTagName("number").item(0).getTextContent();
This should give me something like:
Name | Number
A |
B |
C | 001
But I get:
Name | Number
A | 001
B | 001
C | 001
So, I think the getElementsByTagName("Number") is looking for number node in all the children of a node. I don't want that. Does anybody know a workaround?
I thought of using XPath instead of the above method, but I really want to know if there's an existing way. Thanks

You can use the javax.xml.xpath APIs in the JDK/JRE to have much more control over the XML returned over getElementsByTagName.
import java.io.File;
import javax.xml.parsers.*;
import javax.xml.xpath.*;
import org.w3c.dom.*;
public class Demo {
public static void main(String[] args) throws Exception {
DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
Document document = docBuilder.parse(new File("filename.xml"));
XPathFactory xpathFactory = XPathFactory.newInstance();
XPath xpath = xpathFactory.newXPath();
Element element = (Element) xpath.evaluate("//node3/name", document, XPathConstants.NODE);
}
}

Hope this helps,
import java.io.File;
import java.io.IOException;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
public class XML {
public static void main(String[] args) throws IOException {
File input = new File("D:\\sample.xml");
Document doc = Jsoup.parse(input, "UTF-8");
Elements allElements = doc.select("root");
for(Element value : allElements){
System.out.println(value.text());
}
String node3Num = doc.select("node3").tagName("number").text();
System.out.println(node3Num);
}
}
Output:
A B C 001
C 001
I have used jsoup-1.7.2 jar (you can download from jsoup.org)

Assuming that your eElement variable is always one of the <node1/>, <node2/>, … elements in question, then the following code should work when you replace your own snippet mentioned above:
String number = null;
NodeList childNodes = eElement.getChildNodes();
for (int i = 0; i < childNodes.getLength(); i++) {
Node node = childNodes.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE
&& node.getNodeName().equals("number")) {
number = node.getTextContent();
break;
}
}
The number variable will be null when there is no <number/> child; it will contain the number you need otherwise.

Get XML nodes from certain tree level

I need a method like Document.getElementsByTagName(), but one that searches only tags from a certain level (ie, not nested tags with the same name)
Example file:
<script>
<something>
<findme></findme><!-- DO NOT FIND THIS TAG -->
</something>
<findme></findme><!-- FIND THIS TAG -->
</script>
Document.getElementsByTagName() simply returns all findme tags in the document.

Here is an example with XPath
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
public class TestXPath {
private static final String FILE = "a.xml" ;
private static final String XPATH = "/script/findme";
public static void main(String[] args) {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
docFactory.setNamespaceAware(true);
DocumentBuilder builder;
try {
builder = docFactory.newDocumentBuilder();
Document doc = builder.parse(FILE);
XPathExpression expr = XPathFactory.newInstance().newXPath().compile(XPATH);
Object hits = expr.evaluate(doc, XPathConstants.NODESET ) ;
if ( hits instanceof NodeList ) {
NodeList list = (NodeList) hits ;
for (int i = 0; i < list.getLength(); i++ ) {
System.out.println( list.item(i).getTextContent() );
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
With
<script>
<something>
<findme>1</findme><!-- DO NOT FIND THIS TAG -->
</something>
<findme>Find this</findme><!-- FIND THIS TAG -->
<findme>More of this</findme><!-- FIND THIS TAG AS WELL -->
</script>
It yields
Find this
More of this

If you're using DOM, the only way I can think of would be a recursive function that looks at the children of each element.

Use:
/*/findme
This XPath expression selects all findme elements that are children of the top element of the XML document.
This expression:
//findme[count(ancestor::*) = 5]
selects all findme elements in the XML document that have exactly five ancestor - elements -- that is, they all are at "level 6".

using conditions in XPath expressions

I need to parse through an XML document in the database and search for a given expression in it. Then, I must return a String value if the given expression is present in the XML else I need to parse through the next expression and return another String value and so on.
I achieved this by using the following code:
// An xml document is passed as a Node when getEntryType() method is called
public static class XMLTextFields {
public static String getEntryType(Node target) throws XPathExpressionException {
XPathFactory factory = XPathFactory.newInstance();
XPath xpath = factory.newXpath();
String entryType = null;
String [] expression = new String [] {"./libx:package", "./libx:libapp", "./libx:module"};
String [] type = new String [] {"Package", "Libapp", "Module" };
for (int i = 0; i < 3; i ++) {
XPathExpression expr = xpath.compile(expression[i]);
Object result = expr.evaluate(target, XPathConstants.NODESET);
NodeList nodes = (NodeList) result;
if (nodes.getLength() == 0)
continue;
entryType = (type[i]);
}
return entryType;
}
}
I am wondering if there is a simpler way to do this? Meaning, is there a way to use the "expression" like a function which returns a string if the expression is present in the xml.
I am guessing I should be able to do something like this but am not exactly sure:
String [] Expression = new String [] {"[./libx:package]\"Package\"", ....}
Meaning, return "Package" if libx:package node exists in the given XML

If your XPath processor is version 2, you can use if expressions: http://www.w3.org/TR/xpath20/#id-conditionals .

You can use XSLT here. In XSLT you can check the node name by using
<xsl:value-of select="*[starts-with(name(),'libx:package')]" />
OR you can check using
<xsl:if select="name()='libx:package'" >
<!-- Your cusotm elements here... -->
</xsl:if>
You can check existence of Element OR Attribute this way to validate specific needs.
hope this helps.

Yes there is, just use an XPath functions in your expression:
Expression exp = xpath.compile("local-name(*[local-name() = 'package'])")
// will return "package" for any matching elements
exp.evaluate(target, XPathConstants.STRING);
But this will return "package" instead of "Package". Note the capital P
Below is the Test code:
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import java.util.Map;
import java.util.HashMap;
public class Test {
private static Map<String, String> mappings = new HashMap<String, String>();
static {
mappings.put("package", "Package");
mappings.put("libapp", "Application");
mappings.put("module", "Module");
}
public static void main(String[] args) throws Throwable {
XPathFactory factory = XPathFactory.newInstance();
XPath xpath = factory.newXPath();
String entryType = null;
XPathExpression [] expressions = new XPathExpression[] {
xpath.compile("local-name(*[local-name() = 'package'])"),
xpath.compile("local-name(*[local-name() = 'libapp'])"),
xpath.compile("local-name(*[local-name() = 'module'])")
};
DocumentBuilderFactory fac = DocumentBuilderFactory.newInstance();
DocumentBuilder parser = fac.newDocumentBuilder();
Document doc = parser.parse(args[0]);
for(int i = 0; i < expressions.length; i++) {
String found = (String) expressions[i].evaluate(doc.getDocumentElement(),
XPathConstants.STRING);
entryType = mappings.get(found);
if(entryType != null && !entryType.trim().isEmpty()) {
break;
}
}
System.out.println(entryType);
}
}
Contents of text file:
<?xml version="1.0"?>
<root xmlns:libx="urn:libex">
<libx:package>mypack</libx:package>
<libx:libapp>myapp</libx:libapp>
<libx:module>mymod</libx:module>
</root>

In XPath 1.0
concat(translate(substring(local-name(libx:package|libx:libapp|libx:module),
1,
1),
'plm',
'PLM'),
substring(local-name(libx:package|libx:libapp|libx:module),2))
EDIT: It was dificult to understand the path because there was not provided input sample...

#ALL: Thanks!
I used:
XPathExpression expr = xpath.compile("concat(substring('Package',0,100*boolean(//libx:package))," + "substring('Libapp',0,100*boolean(//libx:libapp)),substring('Module',0,100*boolean(//libx:module)))");
expr.evaluate(target, XPathConstants.STRING);