FULL PRODUCT VERSION :
java version "1.5.0_06"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_06-b05)
Java HotSpot(TM) Client VM (build 1.5.0_06-b05, mixed mode, sharing)


ADDITIONAL OS VERSION INFORMATION :
Linux ronny 2.6.12-1-686 #1 Tue Sep 27 12:52:50 JST 2005 i686 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
Short background info: I am the author of Pauker (http://pauker.sourceforge.net/). It's a flashcard program that uses XML to store the lesson files. I got a bugreport from a user who pasted text from the clipboard to the flashcards. Result was that he could no longer open the lesson. After evaluating the problem I found out that the problem is that the Transformer produces invalid XML when it gets fed some "special" characters.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile and execute the attached test case.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expect to see no Exception.
ACTUAL -
I saw an org.xml.sax.SAXParseException.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
[Fatal Error] :2:48: Character reference "&#1" is an invalid XML character.
org.xml.sax.SAXParseException: Character reference "&#1" is an invalid XML character.
        at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(DOMParser.java:264)
        at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:292)
        at XMLTest.main(XMLTest.java:43)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.io.ByteArrayOutputStream;
import java.io.StringReader;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.*;
import org.xml.sax.InputSource;

public class XMLTest {
    
    public static void main(String[] args) {
        
        String string = new String("Via copy & paste you can insert \"\u0001\" into a JTextArea.");
        
        try {
            // create document
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            DocumentBuilder documentBuilder = dbf.newDocumentBuilder();
            Document document = documentBuilder.newDocument();
            
            // add text element
            Element textElement = document.createElement("Text");
            Text text = document.createTextNode(string);
            textElement.appendChild(text);
            document.appendChild(textElement);

            // transform to XML
            TransformerFactory tf = TransformerFactory.newInstance();
            Transformer transformer = tf.newTransformer();
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            DOMSource source = new DOMSource(document);
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            StreamResult result = new StreamResult(outputStream);
            transformer.transform(source, result);
            String xmlString = outputStream.toString();
            System.out.println("xmlString:\n" + xmlString);
            
            // try parsing
            StringReader reader = new StringReader(xmlString);
            InputSource inputSource = new InputSource(reader);
            // triggers org.xml.sax.SAXParseException!
            Document document2 = documentBuilder.parse(inputSource);
            
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

---------- END SOURCE ----------