Java XML via Dom auslesen

package de.tm.android.allgemeinwissen;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

public class Database {
	public void readXML(File file) {
		FileInputStream fis;
		try {
			fis = new FileInputStream(file);

			DocumentBuilderFactory factory = DocumentBuilderFactory
					.newInstance();
			DocumentBuilder builder = factory.newDocumentBuilder();
			Document dom = builder.parse(fis);
			Element root = dom.getDocumentElement();		
			NodeList rows = root.getElementsByTagName("Row");
			
			//Alle Zeilen durchlaufen
			for (int i = 0; i < rows.getLength(); i++) {
				Node row = rows.item(i);
				NodeList childNodes = row.getChildNodes();
				
				//Attribute der Zeile(Frage) auslesen
				for(int b = 0; b<childNodes.getLength(); b++)
				{
					Node attr = childNodes.item(b); //und nun?
				}
			}
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

<table name="fragenkatalog">
	<row>
		<id>2</id>
		<category>1</category>
		<question>Wann war der Erste Weltkrieg ?</question>
		<answer1>1939 - 1945</answer1>
		<answer2>1967 - 1971</answer2>
		<answer3>1914 - 1918</answer3>
		<answer4>1889 - 1895</answer4>
		<correct_answer>3</correct_answer>
		<difficulty>1</difficulty>
	</row>
	<row>
		<id>3</id>
		<category>1</category>
		<question>Wann war der Zweite Weltkrieg ?</question>
		<answer1>1939 - 1945</answer1>
		<answer2>1967 - 1971</answer2>
		<answer3>1914 - 1918</answer3>
		<answer4>1889 - 1895</answer4>
		<correct_answer>1</correct_answer>
		<difficulty>1</difficulty>
	</row>
	<row>
		<id>4</id>
		<category>1</category>
		<question>Wann war der Dreißigjährige Krieg ?</question>
		<answer1>1618 - 1648</answer1>
		<answer2>1718 - 1748</answer2>
		<answer3>1518 - 1548</answer3>
		<answer4>1418 - 1448</answer4>
		<correct_answer>1</correct_answer>
		<difficulty>1</difficulty>
	</row>
	<row>
		<id>5</id>
		<category>3</category>
		<question>Wodurch wurde der Dreißigjährige Krieg 1648 beendet ?</question>
		<answer1>Westfälischer Frieden</answer1>
		<answer2>Bayerischer Frieden</answer2>
		<answer3>Hessischer Frieden</answer3>
		<answer4>Sächsischer Frieden</answer4>
		<correct_answer>1</correct_answer>
		<difficulty>1</difficulty>
	</row>
</table>

package de.tm.android.allgemeinwissen;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.ArrayList;

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 Database {
	public static ArrayList<Question> readXML(InputStream fis) throws Exception {
		
		ArrayList<Question> questionList = new ArrayList<Question>();
		try {
			//FileInputStream fis = new FileInputStream(file);

			DocumentBuilderFactory factory = DocumentBuilderFactory
					.newInstance();
			DocumentBuilder builder = factory.newDocumentBuilder();
			Document dom = builder.parse(fis);
			Element root = dom.getDocumentElement();
			NodeList rows = root.getElementsByTagName("Row");			
			// Alle Zeilen durchlaufen
			for (int i = 0; i < rows.getLength(); i++) {
				try {

					// Frage variablen initialisieren
					int id = 0;
					int category = 0;
					String question = "";
					String answer1 = "";
					String answer2 = "";
					String answer3 = "";
					String answer4 = "";
					int correct = 0;
					int difficulty = 0;

					Node row = rows.item(i);
					NodeList childNodes = row.getChildNodes();

					// Attribute der Zeile(Frage) auslesen
					for (int b = 0; b < childNodes.getLength(); b++) {
						Node attr = childNodes.item(b);
						if (attr.getNodeName().equals("id")) {
							id = Integer.getInteger(attr.getNodeValue());
						} else if (attr.getNodeName().equals("category")) {
							category = Integer.getInteger(attr.getNodeValue());
						} else if (attr.getNodeName().equals("question")) {
							question = attr.getNodeValue();
						} else if (attr.getNodeName().equals("answer1")) {
							answer1 = attr.getNodeValue();
						} else if (attr.getNodeName().equals("answer2")) {
							answer2 = attr.getNodeValue();
						} else if (attr.getNodeName().equals("answer3")) {
							answer3 = attr.getNodeValue();
						} else if (attr.getNodeName().equals("answer4")) {
							answer4 = attr.getNodeValue();
						} else if (attr.getNodeName().equals("correct_answer")) {
							correct = Integer.getInteger(attr.getNodeValue());
						} else if (attr.getNodeName().equals("difficulty")) {
							difficulty = Integer
									.getInteger(attr.getNodeValue());
						}
					}
					
					String[] answer = {answer1,answer2,answer3,answer4};
						
					Question frage = new Question(id, question,
							answer, correct, category);
					
					questionList.add(frage);		
				} catch (Exception e) {
					// do nothing
				}
				
			}			
		} catch (Exception e) {
			throw e;
		}
		return questionList;
	}
}