Question

I’m using the following code with the javax.swing.text.html.parser.ParserDelegator in order to parse hyperlinks from a website.

InputStream inputStream;
InputStreamReader inputStreamReader;
inputStream = rsc.getUrl().openStream();
inputStreamReader = new InputStreamReader(inputStream);
ParserDelegator parserDelegator = new ParserDelegator();
ParserCallback parserCallback = new ParserCallback() {
    public void handleStartTag(Tag tag, MutableAttributeSet attribute, int pos) {
        if (tag == Tag.A) {
            String address = (String) attribute.getAttribute(Attribute.HREF);
            if ((address != null) && !address.equalsIgnoreCase("null"))
                links.add(address);
        }
    }
    public void handleSimpleTag(Tag t, MutableAttributeSet a, final int pos) { }
    public void handleEndTag(Tag t, final int pos) { }
    public void handleComment(final char[] data, final int pos) { }
    public void handleText(final char[] data, final int pos) { }
    public void handleError(final java.lang.String errMsg, final int pos) { }
};
parserDelegator.parse(inputStreamReader, parserCallback, false);

This worked fine for most sites, but for example, when I’m trying to open http://www.univie.ac.at, I receive the following exception:

javax.swing.text.ChangedCharSetException
    at javax.swing.text.html.parser.DocumentParser.handleEmptyTag(DocumentParser.java:172)
    at javax.swing.text.html.parser.Parser.startTag(Parser.java:413)
    at javax.swing.text.html.parser.Parser.parseTag(Parser.java:1943)
    at javax.swing.text.html.parser.Parser.parseContent(Parser.java:2061)
    at javax.swing.text.html.parser.Parser.parse(Parser.java:2228)
    at javax.swing.text.html.parser.DocumentParser.parse(DocumentParser.java:105)
    at javax.swing.text.html.parser.ParserDelegator.parse(ParserDelegator.java:84)

How would I go about catching this exception, but still keep parsing my remote document (e.g. my InputStream)?

Answer 1

The easiest way I found was just to ignore the charset completely:

Change

parserDelegator.parse(inputStreamReader, parserCallback, false);

to:

parserDelegator.parse(inputStreamReader, parserCallback, true);

Since the third option is boolean ignoreCharSet.