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. */ import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.File; import java.util.ArrayList; import java.util.List; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; /** * * @author Mershack */ @WebServlet(urlPatterns = { "/ManageViewerFiles" }) public class ManageViewerFiles extends HttpServlet { /** * Processes requests for both HTTP <code>GET</code> and <code>POST</code> * methods. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); try { //get the viewer files //add more files //delete some files /* TODO output your page here. You may use following sample code. */ String command = request.getParameter("command"); String viewerid = request.getParameter("viewerid"); //System.out.println("Hello World"); //System.out.println(command); //System.out.println(studyid); if (command.equalsIgnoreCase("getViewerFiles")) { //getting viewer files //first get the filenames in the directory. //I will get the list of files in this directory and send it String studyPath = getServletContext().getRealPath("/viewer/" + viewerid); File root = new File(studyPath); File[] list = root.listFiles(); ArrayList<String> fileItemList = new ArrayList<String>(); if (list == null) { System.out.println("List is null"); return; } for (File f : list) { if (f.isDirectory()) { ArrayList<String> dirItems = getFileItems(f.getAbsolutePath(), f.getName()); for (int i = 0; i < dirItems.size(); i++) { fileItemList.add(dirItems.get(i)); } } else { //System.out.println(f.getName()); fileItemList.add(f.getName()); } } System.out.println("**** Printing the fileItems now **** "); String outputStr = ""; for (int i = 0; i < fileItemList.size(); i++) { outputStr += fileItemList.get(i) + "::::"; } out.println(outputStr); } else if (command.equalsIgnoreCase("addViewerFiles")) { //add the files //get the files and add them String studyFolderPath = getServletContext().getRealPath("/viewer/" + viewerid); File studyFolder = new File(studyFolderPath); //process only if its multipart content if (ServletFileUpload.isMultipartContent(request)) { try { List<FileItem> multiparts = new ServletFileUpload(new DiskFileItemFactory()) .parseRequest(request); int cnt = 0; for (FileItem item : multiparts) { if (!item.isFormField()) { // cnt++; String name = new File(item.getName()).getName(); //write the file to disk if (!studyFolder.exists()) { studyFolder.mkdir(); System.out.println("The Folder has been created"); } item.write(new File(studyFolder + File.separator + name)); System.out.println("File name is :: " + name); } } out.print("Files successfully uploaded"); } catch (Exception ex) { //System.out.println("File Upload Failed due to " + ex); out.print("File Upload Failed due to " + ex); } } else { // System.out.println("The request did not include files"); out.println("The request did not include files"); } } else if (command.equalsIgnoreCase("deleteViewerFiles")) { //get the array of files and delete thems String[] mpk; //get the array of file-names mpk = request.getParameterValues("fileNames"); for (int i = 0; i < mpk.length; i++) { String filePath = getServletContext().getRealPath("/viewer/" + viewerid + "/" + mpk[i]); File f = new File(filePath); f.delete(); } } //out.println("</html>"); } catch (Exception ex) { ex.printStackTrace(); } finally { out.close(); } } public String getServerUrl(HttpServletRequest request) { String uri = request.getScheme() + "://" + // "http" + ":// request.getServerName() + // "myhost" ":" + // ":" request.getServerPort() + // "8080" request.getRequestURI();//+ // "/people" int lastbackslash = uri.lastIndexOf("/"); return uri.substring(0, lastbackslash); } public ArrayList<String> getFileItems(String studyurl, String dir) { ArrayList<String> fileNames = new ArrayList<String>(); try { //System.out.println(studyurl); File root = new File(studyurl); File[] list = root.listFiles(); //ArrayList<String> fileItems = new ArrayList<String>(); if (list == null) { System.out.println("It is null"); return null; } for (File f : list) { if (f.isDirectory()) { getFileItems(f.getAbsolutePath(), dir); System.out.println("Dir:" + f.getName()); } else { fileNames.add(dir + "/" + f.getName()); ///System.out.println("File:" + dir + "/" + f.getName()); } //fileNames.add(f.getAbsolutePath()); } } catch (Exception ex) { ex.printStackTrace(); } return fileNames; } // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code."> /** * Handles the HTTP <code>GET</code> method. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } /** * Handles the HTTP <code>POST</code> method. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } /** * Returns a short description of the servlet. * * @return a String containing servlet description */ @Override public String getServletInfo() { return "Short description"; }// </editor-fold> }