public Codec( String extension, Class iCodecClass )
        {
            extensionRegX = "";
            // Make sure an extension was specified:
            if( extension != null && extension.length() > 0 )
            {
                // We are only interested in the file extension.  The filename
                // can begin with whatever:
                extensionRegX = ".*";
                String c;
                for( int x = 0; x < extension.length(); x++ )
                {
                    // Each character could be either upper or lower case:
                    c = extension.substring( x, x + 1 );
                    extensionRegX += "[" + c.toLowerCase( Locale.ENGLISH )
                                     + c.toUpperCase( Locale.ENGLISH ) + "]";
                }
                // The extension will be at the end of the filename:
                extensionRegX += "$";
            }
            // remember the codec to use for this format:
            this.iCodecClass = iCodecClass;
        }