edu.lternet.pasta.portal.MetadataPreviewerServlet.java Source code

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Here is the source code for edu.lternet.pasta.portal.MetadataPreviewerServlet.java

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/*
 *
 * $Date$
 * $Author$
 * $Revision$
 *
 * Copyright 2011,2012 the University of New Mexico.
 *
 * This work was supported by National Science Foundation Cooperative
 * Agreements #DEB-0832652 and #DEB-0936498.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0.
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 */

package edu.lternet.pasta.portal;

import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.List;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;

import edu.lternet.pasta.client.EmlUtility;

public class MetadataPreviewerServlet extends DataPortalServlet {

    /**
     * Class variables
     */

    private static final Logger logger = Logger.getLogger(edu.lternet.pasta.portal.MetadataPreviewerServlet.class);
    private static final long serialVersionUID = 1L;

    private static String cwd = null;
    private static String xslpath = null;

    /**
     * Constructor of the object.
     */
    public MetadataPreviewerServlet() {
        super();
    }

    /**
     * Destruction of the servlet. <br>
     */
    public void destroy() {
        super.destroy(); // Just puts "destroy" string in log
        // Put your code here
    }

    /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        this.doPost(request, response);

    }

    /**
     * The doPost method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to post.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        HttpSession httpSession = request.getSession();
        String uid = (String) httpSession.getAttribute("uid");
        String forward = "./metadataViewer.jsp";

        if (uid == null || uid.isEmpty())
            uid = "public";

        String html = null;

        boolean isMultipart = ServletFileUpload.isMultipartContent(request);

        if (isMultipart) {

            // Create a factory for disk-based file items
            FileItemFactory factory = new DiskFileItemFactory();

            // Create a new file upload handler
            ServletFileUpload upload = new ServletFileUpload(factory);

            // Parse the request
            try {

                List /* FileItem */ items = upload.parseRequest(request);

                // Process the uploaded items
                Iterator iter = items.iterator();

                while (iter.hasNext()) {

                    FileItem item = (FileItem) iter.next();

                    if (!(item.isFormField())) {

                        String eml = processUploadedFile(item);

                        EmlUtility emlUtility = new EmlUtility(eml);
                        html = emlUtility.xmlToHtmlSaxon(cwd + xslpath, null);
                    }

                }

            } catch (Exception e) {
                handleDataPortalError(logger, e);
            }
        }

        request.setAttribute("metadataHtml", html);
        RequestDispatcher requestDispatcher = request.getRequestDispatcher(forward);
        requestDispatcher.forward(request, response);
    }

    /**
     * Initialization of the servlet. <br>
     *
     * @throws ServletException if an error occurs
     */
    public void init() throws ServletException {

        PropertiesConfiguration options = ConfigurationListener.getOptions();
        xslpath = options.getString("emlutility.xslpath");
        cwd = options.getString("system.cwd");

    }

    private String processUploadedFile(FileItem item) throws Exception {

        String eml = null;

        // Process a file upload
        if (!item.isFormField()) {
            InputStream uploadedStream = item.getInputStream();
            eml = IOUtils.toString(uploadedStream);
            uploadedStream.close();
        }

        return eml;
    }

}