HTML tags/filter/UTF-8

[Dave Hodson]

A question for the list:

I have an input form, which is handled via Struts and the input is validated, 
URLEncoded with UTF-8 and stored in a DB
At a later date, the user can modify their input. The input is displayed with an 
html:text tag, but unfortunately, it does not display properly.
Specifically, the issue is that a URLEncoded character like "堂" (堂, a 
building in Traditional Chinese) is modified before being written out
It goes from "堂" to ""堂", which then displays incorrectly in the 
browser.

Walking through the code, the BaseFieldTag class calls

            results.append(ResponseUtils.filter(value.toString()));

which changes all "harmful" characters to HTML "friendly" ones.  The filter method is 
straightforward enough, but doesn't seem to handle the case where a '&' is followed 
immediately by a '#' character.  My first thought is to simply extend the HTML text 
and textarea classes to add this simple case, but it seems like anyone working on a 
multi-lingual site should have encountered this issue. (In other words, I can't be the 
first guy to run into this, so I must be doing something wrong!)

Any suggestions? It seems that the html: tags are missing the filter attribute that 
bean:write has, but again, I must be missing something...

I've pasted the filter method from ResponseUtils below.  

Regards

Dave



    public static String filter(String value) {

        if (value == null)
            return (null);

        char content[] = new char[value.length()];
        value.getChars(0, value.length(), content, 0);
        StringBuffer result = new StringBuffer(content.length + 50);
        for (int i = 0; i < content.length; i++) {
            switch (content[i]) {
            case '<':
                result.append("&lt;");
                break;
            case '>':
                result.append("&gt;");
                break;
            case '&':
                result.append("&amp;");
                break;
            case '"':
                result.append("&quot;");
                break;
            case '\'':
                result.append("&#39;");
                break;
            default:
                result.append(content[i]);
            }
        }
        return (result.toString());

    }