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 com.pagoadalabs.fileupload.controller; import java.io.*; import java.util.*; 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.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.apache.commons.io.output.*; /** * * @author Dell */ public class FileController extends HttpServlet { private boolean isMultipart; private String filePath; private int maxFileSize = 50 * 1024; private int maxMemSize = 4 * 1024; private File file; public void init() { // Get the file location where it would be stored. filePath = getServletContext().getInitParameter("file-upload"); }; /** * 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"); try (PrintWriter out = response.getWriter()) { /* TODO output your page here. You may use following sample code. */ out.println("<!DOCTYPE html>"); out.println("<html>"); out.println("<head>"); out.println("<title>Servlet FileController</title>"); out.println("</head>"); out.println("<body>"); out.println("<h1>Servlet FileController at " + request.getContextPath() + "</h1>"); out.println("</body>"); out.println("</html>"); } } // <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 { request.getRequestDispatcher("fileupload.jsp").forward(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 { // Check that we have a file upload request isMultipart = ServletFileUpload.isMultipartContent(request); response.setContentType("text/html"); java.io.PrintWriter out = response.getWriter(); if (!isMultipart) { out.println("<html>"); out.println("<head>"); out.println("<title>Servlet upload</title>"); out.println("</head>"); out.println("<body>"); out.println("<p>No file uploaded</p>"); out.println("</body>"); out.println("</html>"); return; } DiskFileItemFactory factory = new DiskFileItemFactory(); // maximum size that will be stored in memory factory.setSizeThreshold(maxMemSize); // Location to save data that is larger than maxMemSize. factory.setRepository(new File("e://temp")); // Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory); // maximum file size to be uploaded. upload.setSizeMax(maxFileSize); try { // Parse the request to get file items. List fileItems = upload.parseRequest(request); // Process the uploaded file items Iterator i = fileItems.iterator(); out.println("<html>"); out.println("<head>"); out.println("<title>Servlet upload</title>"); out.println("</head>"); out.println("<body>"); while (i.hasNext()) { FileItem fi = (FileItem) i.next(); if (!fi.isFormField()) { // Get the uploaded file parameters String fieldName = fi.getFieldName(); String fileName = fi.getName(); String contentType = fi.getContentType(); boolean isInMemory = fi.isInMemory(); long sizeInBytes = fi.getSize(); // Write the file if (fileName.lastIndexOf("\\") >= 0) { file = new File(filePath + fileName.substring(fileName.lastIndexOf("\\"))); } else { file = new File(filePath + fileName.substring(fileName.lastIndexOf("\\") + 1)); } fi.write(file); out.println("Uploaded Filename: " + fileName + "<br>"); } } out.println("</body>"); out.println("</html>"); } catch (Exception ex) { System.out.println(ex); } } /** * Returns a short description of the servlet. * * @return a String containing servlet description */ @Override public String getServletInfo() { return "Short description"; }// </editor-fold> }