public String export() {        HttpServletResponse response = ServletActionContext.getResponse();        filename = filename==null?"chart":filename;        ServletOutputStream out = null;        try {            out = response.getOutputStream();        } catch (IOException e1) {            e1.printStackTrace();        }        if (null != type && null != svg) {            svg = this.handleSvg(svg);            String ext = "";            Transcoder t = null;            if (type.equals("image/png")) {                ext = "png";                t = new PNGTranscoder();            } else if (type.equals("image/jpeg")) {                ext = "jpg";                t = new JPEGTranscoder();            } else if (type.equals("application/pdf")) {                ext = "pdf";                t =(Transcoder) new PDFTranscoder();            } else if(type.equals("image/svg+xml"))                 ext = "svg";               response.addHeader("Content-Disposition", "attachment; filename="+ filename + "."+ext);            response.addHeader("Content-Type", type);                        if (null != t) {                TranscoderInput input = new TranscoderInput(new StringReader(svg));                TranscoderOutput output = new TranscoderOutput(out);                try {                    t.transcode(input, output);                } catch (TranscoderException e) {                    try {                        out.print("Problem transcoding stream. See the web logs for more details.");                    } catch (IOException e1) {                        e1.printStackTrace();                    }                    e.printStackTrace();                }            } else if (ext.equals("svg")) {                try {                    OutputStreamWriter writer = new OutputStreamWriter(out, "UTF-8");                    writer.append(svg);                    writer.close();                } catch (UnsupportedEncodingException e) {                    e.printStackTrace();                }catch (IOException e1) {                    e1.printStackTrace();                }            } else                try {                    out.print("Invalid type: " + type);                } catch (IOException e) {                    e.printStackTrace();                }        } else {            response.addHeader("Content-Type", "text/html");            try {                out.println("Usage:\n\tParameter [svg]: The DOM Element to be converted." +                        "\n\tParameter [type]: The destination MIME type for the elment to be transcoded.");            } catch (IOException e) {                e.printStackTrace();            }        }        try {            out.flush();            out.close();        } catch (IOException e) {            e.printStackTrace();        }        return null;    }