Java tutorial
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package CourseFileManagementSystem; import common.DB; import common.ResultList; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.List; import java.util.Scanner; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServlet; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.apache.commons.io.FilenameUtils; /** * * @author zavie_000 */ @WebServlet(name = "Upload", urlPatterns = { "/Upload" }) public class Upload extends HttpServlet { private static final long serialVersionUID = 1L; private static final String DATA_DIRECTORY = "data"; private static final int MAX_FILE_SIZE = 1024 * 1024 * 400; // 400MB private static final int MAX_MEMORY_SIZE = 1024 * 1024 * 5; //5MB private static final int MAX_REQUEST_SIZE = 1024 * 1024 * 500; //500MB String fileName = ""; static String sectionID = ""; public static void setID(String secID) { sectionID = secID; } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); out.write("<html><head></head><body>"); // Check that we have a file upload request if (!ServletFileUpload.isMultipartContent(request)) { // if not, we stop here PrintWriter writer = response.getWriter(); writer.println("Error: Form must has enctype=multipart/form-data."); writer.flush(); return; } // Create a factory for disk-based file items DiskFileItemFactory factory = new DiskFileItemFactory(); // Sets the size threshold beyond which files are written directly to // disk. factory.setSizeThreshold(MAX_MEMORY_SIZE); // Sets the directory used to temporarily store files that are larger // than the configured size threshold. We use temporary directory for // java factory.setRepository(new File(System.getProperty("java.io.tmpdir"))); // constructs the folder where uploaded file will be stored String temp_folder = " "; try { String dataFolder = getServletContext().getRealPath("") + File.separator + DATA_DIRECTORY; temp_folder = dataFolder; File uploadD = new File(dataFolder); if (!uploadD.exists()) { uploadD.mkdir(); } ResultList rs5 = DB.query( "SELECT * FROM course AS c, section AS s, year_semester AS ys, upload_checklist AS uc WHERE s.courseCode = c.courseCode " + "AND s.semesterID = ys.semesterID AND s.courseID = c.courseID AND s.sectionID=" + sectionID); rs5.next(); // Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory); // Sets maximum size of upload file upload.setFileSizeMax(MAX_FILE_SIZE); // Set overall request size constraint upload.setSizeMax(MAX_REQUEST_SIZE); // creates the directory if it does not exist String path1 = getServletContext().getContextPath() + "/" + DATA_DIRECTORY + "/"; String temp_semester = rs5.getString("year") + "-" + rs5.getString("semester"); String real_path = temp_folder + File.separator + temp_semester; File semester = new File(real_path); if (!semester.exists()) { semester.mkdir(); } path1 += temp_semester + "/"; real_path += File.separator; String temp_course = rs5.getString("courseCode") + rs5.getString("courseID") + "-" + rs5.getString("courseName"); String real_path1 = real_path + temp_course; File course = new File(real_path1); if (!course.exists()) { course.mkdir(); } path1 += temp_course + "/"; real_path1 += File.separator; String temp_section = "section-" + rs5.getString("sectionNo"); String real_path2 = real_path1 + temp_section; File section = new File(real_path2); if (!section.exists()) { section.mkdir(); } path1 += temp_section + "/"; real_path2 += File.separator; String sectionPath = path1; // Parse the request List<FileItem> items = upload.parseRequest(request); if (items != null && items.size() > 0) { // iterates over form's fields for (FileItem item : items) { // processes only fields that are not form fields if (!item.isFormField() && !item.getName().equals("")) { String DBPath = ""; System.out.println(item.getName() + " file is for " + item.getFieldName()); Scanner field_name = new Scanner(item.getFieldName()).useDelimiter("[^0-9]+"); int id = field_name.nextInt(); fileName = new File(item.getName()).getName(); ResultList rs = DB.query("SELECT * FROM upload_checklist WHERE checklistID =" + id); rs.next(); String temp_file = rs.getString("label"); String real_path3 = real_path2 + temp_file; File file_type = new File(real_path3); if (!file_type.exists()) file_type.mkdir(); DBPath = sectionPath + "/" + temp_file + "/"; String context_path = DBPath; real_path3 += File.separator; String filePath = real_path3 + fileName; DBPath += fileName; String temp_DBPath = DBPath; int count = 0; File f = new File(filePath); String temp_fileName = f.getName(); String fileNameWithOutExt = FilenameUtils.removeExtension(temp_fileName); String extension = FilenameUtils.getExtension(filePath); String newFullPath = filePath; String tempFileName = " "; while (f.exists()) { ++count; tempFileName = fileNameWithOutExt + "_(" + count + ")."; newFullPath = real_path3 + tempFileName + extension; temp_DBPath = context_path + tempFileName + extension; f = new File(newFullPath); } filePath = newFullPath; System.out.println("New path: " + filePath); DBPath = temp_DBPath; String changeFilePath = filePath.replace('/', '\\'); String changeFilePath1 = changeFilePath.replace("Course_File_Management_System\\", ""); File uploadedFile = new File(changeFilePath1); System.out.println("Change filepath = " + changeFilePath1); System.out.println("DBPath = " + DBPath); // saves the file to upload directory item.write(uploadedFile); String query = "INSERT INTO files (fileDirectory) values('" + DBPath + "')"; DB.update(query); ResultList rs3 = DB.query("SELECT label FROM upload_checklist WHERE id=" + id); while (rs3.next()) { String label = rs3.getString("label"); out.write("<a href=\"Upload?fileName=" + changeFilePath1 + "\">Download " + label + "</a>"); out.write("<br><br>"); } ResultList rs4 = DB.query("SELECT * FROM files ORDER BY fileID DESC LIMIT 1"); rs4.next(); String query2 = "INSERT INTO lecturer_upload (fileID, sectionID, checklistID) values(" + rs4.getString("fileID") + ", " + sectionID + ", " + id + ")"; DB.update(query2); } } } } catch (FileUploadException ex) { throw new ServletException(ex); } catch (Exception ex) { throw new ServletException(ex); } response.sendRedirect(request.getHeader("Referer")); } @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String filePath = request.getParameter("fileName"); if (filePath == null || filePath.equals("")) { throw new ServletException("File Name can't be null or empty"); } File file = new File(filePath); if (!file.exists()) { throw new ServletException("File doesn't exists on server."); } ServletContext ctx = getServletContext(); try (InputStream fis = new FileInputStream(file)) { String mimeType = ctx.getMimeType(file.getAbsolutePath()); response.setContentType(mimeType != null ? mimeType : "application/octet-stream"); response.setContentLength((int) file.length()); response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); try (ServletOutputStream os = response.getOutputStream()) { byte[] bufferData = new byte[1024]; int read = 0; while ((read = fis.read(bufferData)) != -1) { os.write(bufferData, 0, read); } os.flush(); os.close(); fis.close(); } } } }