Java tutorial
/** * * Copyright (C) 2002-2012 "SYSNET International, Inc." * support@sysnetint.com [http://www.sysnetint.com] * * This file is part of OpenEMPI. * * OpenEMPI is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.openempi.webapp.server; import java.io.File; import java.io.IOException; import java.util.List; import javax.servlet.ServletConfig; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; 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.FilenameUtils; import org.apache.log4j.Logger; import org.openhie.openempi.context.Context; import org.openhie.openempi.model.UserFile; import org.openhie.openempi.service.UserManager; public class FileUploadServlet extends HttpServlet { private static File uploadDirectory; private UserManager userManager; private Logger log = Logger.getLogger(getClass()); @Override public void init(ServletConfig config) throws ServletException { super.init(config); if (!Context.isInitialized()) { log.error("The context did not initialize properly."); return; } userManager = Context.getUserManager(); String uploadDirectoryName = Context.getConfiguration().getAdminConfiguration().getConfigFileDirectory(); uploadDirectory = new File(uploadDirectoryName); if (!uploadDirectory.exists()) { uploadDirectory.mkdir(); } log.info("Set the upload directory to: " + uploadDirectory.getAbsolutePath()); } @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { super.doGet(req, resp); } @SuppressWarnings("unchecked") @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { String message = "success"; // process only multipart requests if (ServletFileUpload.isMultipartContent(req)) { // 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(req); String name = null; for (FileItem item : items) { // Store field names if (item.isFormField()) { if (item.getFieldName().equals("name")) { name = new String(item.get()); } continue; } String fileName = item.getName(); // get only the file name not whole path if (fileName != null) { fileName = FilenameUtils.getName(fileName); } File uploadedFile = new File(uploadDirectory, fileName); if (uploadedFile.createNewFile()) { log.debug("Wrote out " + message.length() + " bytes."); item.write(uploadedFile); saveUploadFileEntry(name, fileName, uploadedFile.getAbsolutePath()); } else { log.warn("The file already exists in repository: " + uploadedFile.getAbsolutePath()); message = "This file already exists in the repository."; } } } catch (Exception e) { // resp.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, // "An error occurred while creating the file : " + e.getMessage()); log.error("Failed while attempting to upload file: " + e.getMessage(), e); message = "Failed to upload file. Error is: " + e.getMessage(); } } else { // resp.sendError(HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE, // "Request contents type is not supported by the servlet."); log.warn("Request contents type is not supported by the service."); message = "Upload request contents type is not supported."; } // Set to expire far in the past. resp.setHeader("Expires", "Sat, 6 May 1995 12:00:00 GMT"); // Set standard HTTP/1.1 no-cache headers. resp.setHeader("Cache-Control", "no-store, no-cache, must-revalidate"); // Set IE extended HTTP/1.1 no-cache headers (use addHeader). resp.addHeader("Cache-Control", "post-check=0, pre-check=0"); // Set standard HTTP/1.0 no-cache header. resp.setHeader("Pragma", "no-cache"); resp.setContentType("text/html"); resp.setContentLength(message.length()); resp.setStatus(HttpServletResponse.SC_OK); resp.getWriter().printf(message); } private void saveUploadFileEntry(String name, String filename, String absolutePath) throws IOException { if (name == null || name.length() == 0) { log.error("Attempted to upload a file with a blank name of " + name + " and filename of " + filename); throw new IOException("File name is not valid."); } // TODO: Once user management is plugged in this won't be needed here checkLoggedInUser(); UserFile userFile = new UserFile(name, absolutePath); userFile = userManager.saveUserFile(userFile); log.debug("Saved user file entry: " + userFile); } private void checkLoggedInUser() { String sessionKey = Context.getUserContext().getSessionKey(); if (sessionKey == null) { Context.authenticate("admin", "admin"); } log.debug("Currently logged in user is " + Context.getUserContext().getUser()); } }