Metacat

import java.io.ByteArrayOutputStream;

    public static final String                          DOWNLOAD_ACTION = "Download";

                    clientViewBean.setDocId(request.getParameter("docid"));

                    clientViewBean.setMetaFileDocId(request.getParameter("metadataDocId"));

                    clientViewBean.setQformat(request.getParameter("qformat"));

                } else if (action.equals("Download")) {

                    System.out.println("ClientViewHelper.clientRequest: action = " + action);

                    download(clientViewBean, response);

            response.close();

    public static String getNodeText(XPath xPath, String expression, Node root) {

        Node                        node;

        String                      result = null;

        node = getNode(xPath, expression, root);

        if (node != null && !node.equals(""))

            result = node.getTextContent();

        return(result);

    }

    public static String[] getNodeTextList(XPath xPath, String expression, Node root) {

        NodeList                    nodes;

        String                      result[] = null;

        int                         size;

        try {

            nodes = (NodeList) xPath.evaluate(expression, root, XPathConstants.NODESET);

            if (nodes != null && (size = nodes.getLength()) > 0) {

                result = new String[size];

                for(int i = 0; i < size; i++)

                    result[i] = nodes.item(i).getTextContent();

            }

        } catch (XPathExpressionException ex) {

            ex.printStackTrace();

        }

        return(result);

    }

        String                      result, docId;

        if (clientViewBean.getAction().equals(DOWNLOAD_ACTION)) {

            result = null;

        } else if (docId != null && !docId.equals("")) {

            result = "metacat?action=read&qformat=" +clientViewBean.getQformat()

                    + "&sessionid=" + clientViewBean.getSessionid();

    private void download(ClientView bean, HttpServletResponse response) {

        Properties                      args;

        InputStream                     inStream;

        String                          docId, metaId, fNm = null, pth, txtLst[];

        String                          msg = "File '~' (~) downloaded";

        Node                            branchRoot, metaRoot;

        ByteArrayOutputStream           outStream;

        int                             intMe;

        docId = bean.getDocId();

        metaId = bean.getMetaFileDocId();

        if (docId != null && metaId != null && !docId.equals("") && !metaId.equals("")) {

            //*** Properties args: key=param_value, value=param_name.

            args = new Properties();

            args.put("read", "action");

            try {

                //*** First, retrieve the metadata and get the original filename.

                //*** Also, if this is the metadata, get a list of docId's for the package.

                setMetadataDoc(metaId);

                metaRoot = getMetadataDoc().getDocumentElement();

                if (ClientFgdcHelper.isFGDC(getMetadataDoc())) {

                    //*** FGDC

                    if (docId.equals(metaId)) { //*** This is the metadata file.

                        pth = ClientFgdcHelper.FGDC_DOCID_ROOT_XPATH.replaceFirst("%1s", docId);

                        branchRoot = getNode(xpath, pth, getMetadataDoc());

                        fNm = getNodeText(xpath, ClientFgdcHelper.FGDC_FILE_NAME_XPATH, branchRoot);

                        fNm = toZipFileName(fNm);

                        response.setContentType("application/zip");

                        //*** Get the list of docId's for the entire package.

                        args.put(metaId, "docid");

                        txtLst = getNodeTextList(xpath, ClientFgdcHelper.FGDC_DATA_FILE_NODES_XPATH, branchRoot);

                        for (int i = 0; i < txtLst.length; i++)

                            args.put(txtLst[i], "docid");

                        args.put("zip", "qformat");

                    } else { //*** This is a data file.

                        pth = ClientFgdcHelper.PATH4ANCESTOR.replaceFirst("%1s", docId);

                        pth = pth.replaceFirst("%2s", "digform");

                        branchRoot = getNode(xpath, pth, getMetadataDoc());

                        fNm = getNodeText(xpath, ClientFgdcHelper.FGDC_DATA_FILE_NAME_XPATH, branchRoot);

                        response.setContentType("application/octet-stream");

                        args.put(docId, "docid");

                        args.put("xml", "qformat");

                    }

                    System.out.println("ClientViewHelper.download: docId = " + docId + "  metaId= " + metaId + "\npth = " + pth + "\nfNm = " + fNm);

                } else {

                    //*** TODO: EML -  this is just some basic code to start with.

                    if (docId.equals(metaId)) {

                        fNm = "emlMetadata.xml";

                        txtLst = new String[] {docId};

                        args.put(txtLst[0], "docid");

                        args.put("zip", "qformat");

                        response.setContentType("application/zip");

                    } else {

                        fNm = "emlData.dat";

                        args.put("xml", "qformat");

                        args.put(docId, "docid");

                        response.setContentType("application/octet-stream");

                    }

                }

                //*** Set the filename in the response.

                response.setHeader("Content-Disposition", "attachment; filename=" + fNm);

                //*** Next, read the file from metacat.

                inStream = metacatClient.sendParameters(args);

                //*** Then, convert the input stream into an output stream.

                outStream = new ByteArrayOutputStream();

                while ((intMe = inStream.read()) != -1) {

                    outStream.write(intMe);

                }

                //*** Now, write the output stream to the response.

                response.setContentLength(outStream.size());

                outStream.writeTo(response.getOutputStream());

                response.flushBuffer();

                //*** Finally, set the message for the user interface to display.

                msg = msg.replaceFirst("~", fNm);

                msg = msg.replaceFirst("~", docId);

                bean.setMessage(ClientView.SELECT_MESSAGE, msg);

            } catch (Exception ex) {

                ex.printStackTrace();

                bean.setMessage(ClientView.SELECT_MESSAGE, ex.getMessage());

            }

        }

    }

    public static String toZipFileName(String fileName) {

        String                      result = "metacat";

        int                         idx;

        if (fileName != null && !fileName.equals("") && !fileName.equals(".")) {

            idx = fileName.indexOf('.');

            if (idx > -1)

                result = fileName.substring(0, idx);

            else

                result = fileName;

        }

        result += ".zip";

        return(result);

    }