Generating HTML

From:

Jason Cavett <jason.cavett@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 03 Oct 2007 23:23:57 -0000

Message-ID:

<1191453837.641207.122370@50g2000hsm.googlegroups.com>

I am attempting to generate HTML within my application for printing
documents. Due to various restrictions, I am using the
javax.swing.text.html.HTMLDocument package. That can't change (unless
it is impossible to do what I want to do).

My method takes in a TableModel and attempts to create an HTML
document from the data in the table, replicating the table within HTML
code. However, when I run the method below, I get the following
exception:

javax.swing.text.StateInvariantError: Illegal cast to
MutableAttributeSet
    at javax.swing.text.AbstractDocument
$AbstractElement.checkForIllegalCast(AbstractDocument.java:2055)
    at javax.swing.text.AbstractDocument
$AbstractElement.addAttributes(AbstractDocument.java:1988)
    at javax.swing.text.AbstractDocument
$AbstractElement.<init>(AbstractDocument.java:1781)
    at javax.swing.text.AbstractDocument
$BranchElement.<init>(AbstractDocument.java:2248)
    at javax.swing.text.html.HTMLDocument
$BlockElement.<init>(HTMLDocument.java:3674)
    at
javax.swing.text.html.HTMLDocument.createBranchElement(HTMLDocument.java:
379)
    at
hasrd.gui.components.print.HasrdDocument.generateHTML(MyHTMLDocumentGenerator.java:
152)
        ...

Is it even possible to do what I want to do? If so, what am I doing
wrong?

Thanks

Here is the method in question. It is self-contained.

    protected void generateHTML(TableModel dataTable) {
        AbstractDocument.AttributeContext ctx = getAttributeContext();

        // create default root element
        BranchElement root = (BranchElement) this.createDefaultRoot();

        // create the table
        AttributeSet atts = ctx.getEmptySet();
        atts = ctx.addAttribute(atts, StyleConstants.NameAttribute,
                HTML.Tag.TABLE);
        BranchElement table = (BranchElement)
createBranchElement(root, atts); // ERROR HAPPENS HERE
        root.replace(0, 0, new Element[] { table });

        // for each row in the table, add a row to the html
        for (int row = 0; row < dataTable.getRowCount(); row++) {
            // create the table
            atts = ctx.getEmptySet();
            atts = ctx.addAttribute(atts,
StyleConstants.NameAttribute,
                    HTML.Tag.TR);
            BranchElement rowTag = (BranchElement)
createBranchElement(table,
                    atts);
            table.replace(0, 0, new Element[] { rowTag });

            // for each column
            for (int col = 0; col < dataTable.getColumnCount(); col++)
{
                // create the cell
                atts = ctx.getEmptySet();
                atts = ctx.addAttribute(atts,
StyleConstants.NameAttribute,
                        HTML.Tag.TD);
                BranchElement cellTag = (BranchElement)
createBranchElement(
                        rowTag, atts);
                rowTag.replace(0, 0, new Element[] { cellTag });

                // put data into leaf node
                atts = ctx.getEmptySet();
                atts = ctx.addAttribute(atts,
StyleConstants.NameAttribute,
                        HTML.Tag.CONTENT);
                atts = ctx.addAttribute(atts,
                        StyleConstants.ComposedTextAttribute,
dataTable
                                .getValueAt(row, col));
                Element leaf = createLeafElement(cellTag, atts, 0, 1);
                cellTag.replace(0, 0, new Element[] { leaf });
            }
        }
    }