An explanation on how to use xml in java to write and save documents.

This java program will help you to read xml value from xml file.

Also you have to download two jar file:
  1 xerces_1_0_3.jar
  2 xmlparserv2.jar

and set class path for above jar files after compile the below java file
================start=============================
import java.io.File;
import org.w3c.dom.Document;
import org.w3c.dom.*;
import java.util.*;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
  public class ReadAndPrintXMLFile{

public static void main(String arg[])
{
 Vector vcrs = null;
try {
  vcrs = null ;
vcrs = new Vector() ;

DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
Document doc = docBuilder.parse (new File("interest.xml"));
  // normalize text representation
doc.getDocumentElement ().normalize ();

  NodeList listOfPersons = doc.getElementsByTagName("interest_master");
int totalPersons = listOfPersons.getLength();
  for(int s=0; s<listOfPersons.getLength() ; s++){

Node firstPersonNode = listOfPersons.item(s);
if(firstPersonNode.getNodeType() == Node.ELEMENT_NODE){

Element firstPersonElement = (Element)firstPersonNode;
  //-------
NodeList firstNameList = firstPersonElement.getElementsByTagName("interest_id");
Element firstNameElement = (Element)firstNameList.item(0);
  NodeList textFNList = firstNameElement.getChildNodes(); System.out.println("First Name : " + ((Node)textFNList.item(0)).getNodeValue().trim());
String id=((Node)textFNList.item(0)).getNodeValue().trim();
vcrs.add(id);
//-------
NodeList lastNameList = firstPersonElement.getElementsByTagName("interest_name");
Element lastNameElement = (Element)lastNameList.item(0);
  NodeList textLNList = lastNameElement.getChildNodes(); System.out.println("Last Name : " + ((Node)textLNList.item(0)).getNodeValue().trim());
String name=((Node)textFNList.item(0)).getNodeValue().trim();
vcrs.add(name);
//----
  //------

}//end of if clause

}//end of for loop with s var

}catch (SAXParseException err) {
System.out.println ("** Parsing error" + ", line " + err.getLineNumber () + ", uri " + err.getSystemId ()); System.out.println(" " + err.getMessage ());
  }catch (SAXException e) {
Exception x = e.getException ();
((x == null) ? e : x).printStackTrace ();
  }catch (Throwable t) {
t.printStackTrace ();
}
//System.exit (0);
System.out.println("size of the vector is " + vcrs.size()) ;
}

}//end of  class ===========================end==================

Below is xml file from which we will read value.
========================start================

  <?xml version="1.0"?>
<interest>
 <interest_master>
  <interest_id>1</interest_id>
  <interest_name>Economics</interest_name>
 </interest_master>
   <interest_master>
  <interest_id>2</interest_id>
  <interest_name>Sports</interest_name>
 </interest_master>

 <interest_master>
  <interest_id>3</interest_id>
  <interest_name>Medical</interest_name>
 </interest_master>
   <interest_master>
  <interest_id>4</interest_id>
  <interest_name>Music</interest_name>
 </interest_master>
   <interest_master>
  <interest_id>5</interest_id>
  <interest_name>Mytest</interest_name>
 </interest_master>
</interest>
======================end==================

Tips by : Mukesh Kamal

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• Java Interview Questions
• Interview Questions in Core Java

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