Apache FileUpload的兩種上傳方式介紹及應(yīng)用_JSP教程
      
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      推薦：jsp/javascript打印九九乘法表代碼
      編程打印九九乘法表，本文介紹兩種實(shí)現(xiàn)方式:jsp表達(dá)式方式j(luò)avascript方式，可以根據(jù)自己的習(xí)慣隨意選擇，感興趣的朋友可以參考下哈
      環(huán)境： 
      tomcat5.6 
      commmons-fileupload-1.3.jar 
      commmons-io-2.4.jar 
      JSP 
      編碼：UTF-8 
      臨時(shí)文件夾：fileupload/tmp相對(duì)于網(wǎng)站根目錄 
      上傳文件保存位置：fileupload 
      Traditional API上傳方式 
      //fileload01.htm 
      復(fù)制代碼 代碼如下:www.wf0088.com
       
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 
      <html> 
      <body> 
      <form method="POST" enctype="multipart/form-data" action="traditionalapi.jsp"> 
      File to upload: <input type="file" name="file" size="40"><br/> 
      <input type="submit" value="Press"> to upload the file! 
      </form> 
      </body> 
      </html> 
       
      //traditionalapi.jsp 
      復(fù)制代碼 代碼如下:www.wf0088.com
       
      <%@page contentType="text/html;charset=UTF-8" pageEncoding="UTF-8" language="java"%> 
      <%@page import="java.io.File"%> 
      <%@page import="java.util.List"%> 
      <%@page import="org.apache.commons.fileupload.*"%> 
      <%@page import="org.apache.commons.fileupload.disk.DiskFileItemFactory"%> 
      <%@page import="org.apache.commons.fileupload.servlet.ServletFileUpload"%> 
      <% 
      request.setCharacterEncoding("UTF-8"); 
      // file less than 10kb will be store in memory, otherwise in file system. 
      final int threshold = 10240; 
      final File tmpDir = new File(getServletContext().getRealPath("/") + "fileupload" + File.separator + "tmp"); 
      final int maxRequestSize = 1024 * 1024 * 4; // 4MB 
      // Check that we have a file upload request 
      if(ServletFileUpload.isMultipartContent(request)) 
      { 
      // Create a factory for disk-based file items. 
      FileItemFactory factory = new DiskFileItemFactory(threshold, tmpDir); 

      // Create a new file upload handler 
      ServletFileUpload upload = new ServletFileUpload(factory); 
      // Set overall request size constraint. 
      upload.setSizeMax(maxRequestSize); 
      List<FileItem> items = upload.parseRequest(request); // FileUploadException 
      for(FileItem item : items) 
      { 
      if(item.isFormField()) //regular form field 
      { 
      String name = item.getFieldName(); 
      String value = item.getString(); 
      %> 
      <h1><%=name%> --> <%=value%></h1> 
      <% 
      } 
      else 
      { //file upload 
      String fieldName = item.getFieldName(); 
      String fileName = item.getName(); 
      File uploadedFile = new File(getServletContext().getRealPath("/") + 
      "fileupload" + File.separator + fieldName + "_" + fileName); 
      item.write(uploadedFile); 
      %> 
      <h1>upload file <%=uploadedFile.getName()%> done!</h1> 
      <% 
      } 
      } 
      } 
      %> 
       
      Streaming API上傳方式 
      //fileupload02.htm 
      復(fù)制代碼 代碼如下:www.wf0088.com
       
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 
      <html> 
      <body> 
      <form method="POST" enctype="multipart/form-data" action="streamingapi.jsp"> 
      File to upload: <input type="file" name="file" size="40"><br/> 
      <input type="submit" value="Press"> to upload the file! 
      </form> 
      </body> 
      </html> 
       
      //streamingapi.jsp 
      復(fù)制代碼 代碼如下:www.wf0088.com
       
      <%@page contentType="text/html;charset=UTF-8" pageEncoding="UTF-8" language="java"%> 
      <%@page import="java.io.*"%> 
      <%@page import="java.util.List"%> 
      <%@page import="org.apache.commons.fileupload.*"%> 
      <%@page import="org.apache.commons.fileupload.util.Streams"%> 
      <%@page import="org.apache.commons.fileupload.servlet.ServletFileUpload"%> 
      <% 
      request.setCharacterEncoding("UTF-8"); 
      // Check that we have a file upload request 
      if(ServletFileUpload.isMultipartContent(request)) 
      { 
      // Create a new file upload handler 
      ServletFileUpload upload = new ServletFileUpload(); 

      // Parse the request 
      FileItemIterator iter = upload.getItemIterator(request); 
      while(iter.hasNext()) 
      { 
      FileItemStream item = iter.next(); 
      String fieldName = item.getFieldName(); 
      InputStream is = item.openStream(); 
      if(item.isFormField()) //regular form field 
      { 
      %> 
      <!-- read a FileItemStream's content into a string. --> 
      <h1><%=fieldName%> --> <%=Streams.asString(is)%></h1> 
      <% 
      } 
      else 
      { //file upload 
      String fileName = item.getName(); 
      File uploadedFile = new File(getServletContext().getRealPath("/") + 
      "fileupload" + File.separator + fieldName + "_" + fileName); 
      OutputStream os = new FileOutputStream(uploadedFile); 
      // write file to disk and close outputstream. 
      Streams.copy(is, os, true); 
      %> 
      <h1>upload file <%=uploadedFile.getName()%> done!</h1> 
      <% 
      } 
      } 
      } 
      %> 
       
      Traditional API vs Streaming API 
      Streaming API上傳速度相對(duì)較快。因?yàn)樗抢脙?nèi)存保存上傳的文件，節(jié)省了傳統(tǒng)API將文件寫入臨時(shí)文件帶來(lái)的開銷。 
      可參考： 
      http://stackoverflow.com/questions/11620432/apache-commons-fileupload-streaming-api 
      This page describes the traditional API of the commons fileupload library. The traditional API is a convenient approach. However, for ultimate performance, you might prefer the faster Streaming API. 
      http://commons.apache.org/proper/commons-fileupload/using.html
      分享：JSP分頁(yè)顯示的實(shí)例代碼
      JSP分頁(yè)顯示的實(shí)例代碼，需要的朋友可以參考一下
      


      

      


      來(lái)源：模板無(wú)憂//所屬分類：JSP教程/更新時(shí)間：2013-04-22


      


      



      


      



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