CODEWITHSUNDEEP
javaxml
user607573
user607573

Reputation: 29

Java XML parsing

I need to extract (using Java) the tag for the given name tag from XML file like this:

Here is my XML file:

<aa>
  <bb>
    <name>k1</name>
    <value>5</value>
  </bb>
  <bb>
    <name>k2</name>
    <value>7</value>
 </bb>
</aa>

Input to function: full path to <name> tag, e.g.: /aa/bb/name=k2
( Output for this example should return 7)

Also more advanced question: I need to extract all name:value pairs from the XML file then the name is given by regular expression I am thinking that XPath is the right tool here, but devil in details.

Upvotes: 2

Views: 1526

Answers (4)

vtd-xml-author
vtd-xml-author

Reputation: 3377

Below is the code of extracting value using vtd-xml.

import com.ximpleware.*;

public class extractValue{
    public static void  main(String s[]) throws VTDException, IOException{
        VTDGen vg = new VTDGen();
        if (!vg.parseFile("input.xml", false));
        VTDNav vn = vg.getNav();
        AutoPilot ap = new AutoPilot(vn);
        ap.selectXPath("/aa/bb[name='k1']/value");
        int i=0;
        while ((i=ap.evalXPath())!=-1){
            System.out.println(" value ===>"+vn.toString(i));
        }   
    }
}

Upvotes: 0

Aliya
Aliya

Reputation: 1178

import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.jdom.xpath.XPath;
import org.junit.Test;

import static org.junit.Assert.*;

import java.io.File;
import java.io.IOException;

import javax.xml.xpath.XPathExpressionException;

public class XmlParsingTest {
    @Test
    public void testParsing() throws XPathExpressionException, JDOMException, IOException {

         SAXBuilder builder = new SAXBuilder();
         File xmlFile = new File("src/test/resources/yourXMLDoc.xml");

         Document origDoc = (Document) builder.build(xmlFile);

         XPath xPathMonsOccCategoryIdInOriginalDoc = XPath.newInstance("//bb[name/text()='k2']/value");

         Element element = (Element) xPathMonsOccCategoryIdInOriginalDoc.selectSingleNode(origDoc.getRootElement());

         assertEquals("7", element.getTextTrim());


}

}

Upvotes: 0

yegor256
yegor256

Reputation: 105063

Try jcabi-xml (see this blog post) with a one-liner:

String found = new XMLDocument(text).xpath("/aa/bb[name='k2']/text()").get(0);

Upvotes: 0

bdoughan
bdoughan

Reputation: 149007

You can use the javax.xml.xpath APIs that are included as part of Java SE 5:

import java.io.FileReader;

import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;

import org.xml.sax.InputSource;

public class Demo {

    public static void main(String[] args) throws Exception {
        XPathFactory xpf = XPathFactory.newInstance();
        XPath xpath = xpf.newXPath();
        XPathExpression xpe = xpath.compile("//bb[name/text()='k2']/value");

        InputSource xml = new InputSource(new FileReader("input.xml"));
        String result = xpe.evaluate(xml);
        System.out.println(result);
    }
}

Upvotes: 2

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