XML and SAX - class returns 'null'

[Laffel]

Hello forum,
I'm currently struggling with parsing an XML-document and store the data properly while parsing. The scenario goes like this

something.xml:

<?xml version="1.0" encoding="UTF-8"?>
<data>
	<phrase id="1" value="something"/>
	<phrase id="2" value="different"/>
</data>

Parser.java:

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;


public class Parser extends DefaultHandler{
	
	private String id, value, something, different;
	// private String xmlfile = "something.xml";
	int index;
	
	public Parser(){
	}
	
	public void parseDocument(){
		try {
			SAXParserFactory factory = SAXParserFactory.newInstance();
			SAXParser parser = factory.newSAXParser();
			DefaultHandler handler = new Parser();
			parser.parse("something.xml", handler);
		}
		catch (Exception e) {
		}
	}
	// start element
	public void startElement(String uri, String localName, String qname, Attributes atts) throws SAXException {
		if(qname.equals("phrase")){
			id = atts.getValue("id");
			value = atts.getValue("value");
		}
		index = Integer.valueOf(id);
	}
	// end element
	public void endElement(String uri, String localName, String qname) throws SAXException{
		doStuff(index, value);
	}
	// switch case manipulation
	public void doStuff(int i, String s){

		switch(i){
		case 1: setSomething(s); break;
		case 2: setDifferent(s); break;
		default: System.out.println("Oh noes!");
		
		}
	}
	
	public void setSomething(String s){
		something = s;
	}
	
	public void setDifferent(String s){
		different = s;
	}
	
	public String getSomething(){
		return something;
	}
	
	public String getDifferent(){
		return different;
	}
}

and the testclass, ParserTest.java

public class ParserTest {

	public static void main(String[] args) {
		Parser p = new Parser();
		p.parseDocument();
		
		System.out.printf("%s %s", p.getSomething(), p.getDifferent());
	}
}

while I expect the output to be "something different" i get "null null". If I print the data while being extracted / parsed I get the correct values...

Any ideas?

// Laffel

[eRaaaa]

Ok, crazy code :)

First: in parseDociument you are creating a new parser object, that is not the same as your parser object in your main method so you never use that to parse/ it will never set the variables of that object
--> change

			DefaultHandler handler = new Parser();
			parser.parse("something.xml", handler);

to
-->

			// DELETE THIS LINE !!! // DefaultHandler handler = new Parser();
			parser.parse("something.xml", this); // use this !

Second: catch (Exception e) {}
that is ugly and you will never see if you get exceptions (and here: you gets an exception on index = Integer.valueOf(id); because it stands outside of your if statement ?!)

Third: move index = Integer.valueOf(id); into your if statement

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;


public class Parser extends DefaultHandler{
	
	private String id, value, something, different;
	// private String xmlfile = "something.xml";
	int index;
	
	public void parseDocument(){
		try {
			SAXParserFactory factory = SAXParserFactory.newInstance();
			SAXParser parser = factory.newSAXParser();
			parser.parse("something.xml", this);
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}
	// start element
	public void startElement(String uri, String localName, String qname, Attributes atts) throws SAXException {
		if(qname.equals("phrase")){
			id = atts.getValue("id");
			value = atts.getValue("value");
			index = Integer.valueOf(id);
		}
	}
	// end element
	public void endElement(String uri, String localName, String qname) throws SAXException{
		doStuff(index, value);
	}
	// switch case manipulation
	public void doStuff(int i, String s){

		switch(i){
		case 1: setSomething(s); break;
		case 2: setDifferent(s); break;
		default: System.out.println("Oh noes!");
		
		}
	}
	
	public void setSomething(String s){
		something = s;
	}
	
	public void setDifferent(String s){
		different = s;
	}
	
	public String getSomething(){
		return something;
	}
	
	public String getDifferent(){
		return different;
	}
}

btw: very complicated way to parse your simple xml file :D

[Laffel]

OMFG! I can't belive that "small" change did the difference... And I can't believe I didn't see it earlier :) I've been though this code for almost two whole days, ripping my hair out...

And yes, this is just a resampled code of what I'm gonna use it for (which is why I dont catch exceptions - yet :D )

Again, thanx for saving my life