在通過使用FileUpload組件上傳的過程中，通過自己的調試，總結如下：1）使用之前的準備，我用的是commons-fileupload-1.1-dev.jar和commons-io-1.1-dev.jar。 解釋一下：儘管有的資料解釋是commons-fileupload-1.0-beta.jar和commons-beanutils.jar，通過調試的結果 顯示並不是需要commons-beanutils.jar檔案，而是由於在parseRequest(request)的類有關繼承於DiskFileItem類。而他有private org.apache.commons.io.output.DeferredFileOutputStream dfos。這樣的就必須使用到commons-io-1.1-dev.jar。因此需要匯入該包。否則就出classNotFound：.DeferredFileOutputStream的錯誤。
2）由於涉及檔案，就涉及到檔案系統。然而在java或應用伺服器中對於檔案系統的訪問，就有一定的安全性原則。 需要將下列許可權添加到您應用程式伺服器的安全性原則檔案中：permission java.io.FilePermission "<<ALL FILES>>", "read,write,delete";具體是添加到..\bea\weblogic81 erver\lib\weblogic.policy中的.否則會可能出如下異常錯誤： org.apache.commons.fileupload.FileUploadException:java.lang.reflect.InvocationTargetExceptionatorg.apache.commons.fileupload.FileUpload.createItem(FileUpload.java:615)atorg.apache.commons.fileupload.FileUpload.parseRequest(FileUpload.java:474)atorg.apache.commons.fileupload.FileUpload.parseRequest(FileUpload.java:355)....
3）對於不同的伺服器，在調試的過程中會出各種不一樣的結果。這個與具體的伺服器有關。
4）由於FileUpload在不斷的更新版本，它的很多方法已經不推薦使用了（這與該組件的不斷的改進有關）。通過對最新的協助文檔和網上的資料寫了一個標準的程式如下：fileUpload檔案：import java.io.IOException;import java.io.PrintWriter;
import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.*;import java.util.*;import java.util.regex.*;import java.io.*;import org.apache.commons.fileupload.servlet.*;import org.apache.commons.fileupload.disk.DiskFileItemFactory;
/* * 建立日期 2005-4-10 * * TODO 要更改此產生的檔案的模板，請轉至 * 視窗 － 喜好設定 － Java － 代碼樣式 － 代碼模板 */
/** * @author gaolong1 * * TODO 要更改此產生的類型注釋的模板，請轉至 * 視窗 － 喜好設定 － Java － 代碼樣式 － 代碼模板 */public class FileUpload extends HttpServlet {
/** * Destruction of the servlet. <br> */ private String uploadPath = "D:\\addnetFile\\"; // 用於存放上傳檔案的目錄 private File tempPath =new File("D:\\addnetFile\\tmp\\"); // 用於存放臨時檔案的目錄 public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here }
/** * The doPost method of the servlet. <br> * * This method is called when a form has its tag value method equals to post. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException{ res.setContentType( "text/html; charset=GB2312"); PrintWriter out=res.getWriter(); System.out.println(req.getContentLength()); System.out.println(req.getContentType()); DiskFileItemFactory factory = new DiskFileItemFactory(); // maximum size that will be stored in memory factory.setSizeThreshold(4096); // the location for saving data that is larger than getSizeThreshold() factory.setRepository(new File("d:\\File\\addnetFile\\temp"));
ServletFileUpload upload = new ServletFileUpload(factory); // maximum size before a FileUploadException will be thrown upload.setSizeMax(1000000); try{ List fileItems = upload.parseRequest(req); // assume we know there are two files. The first file is a small // text file, the second is unknown and is written to a file on // the server Iterator iter = fileItems.iterator();
// 正則匹配，過濾路徑取檔案名稱 String regExp=".+\\\\(.+)$";
// 過濾掉的檔案類型 String[] errorType={".exe",".com",".cgi",".asp"}; Pattern p = Pattern.compile(regExp); while (iter.hasNext()) { FileItem item = (FileItem)iter.next(); //忽略其他不是檔案域的所有表單資訊 if (!item.isFormField()) { String name = item.getName(); long size = item.getSize(); if((name==null||name.equals("")) && size==0) continue; Matcher m = p.matcher(name); boolean result = m.find(); if (result){ for (int temp=0;temp<errorType.length;temp++){ if (m.group(1).endsWith(errorType[temp])){ throw new IOException(name+": wrong type"); } } try{
// 儲存上傳的檔案到指定的目錄
// 在下文中上傳檔案至資料庫時，將對這裡改寫 item.write(new File("d:\\" + m.group(1)));
out.print(name+" "+size+"<br>"); } catch(Exception e){ out.println(e); }
} else { throw new IOException("fail to upload"); } } } } catch (IOException e){ out.println(e); } catch (FileUploadException e){ out.println(e); }
// 儲存上傳的檔案到指定的目錄
// 在下文中上傳檔案至資料庫時，將對這裡改寫
}
/** * Initialization of the servlet. <br> * * @throws ServletException if an error occure */ public void init() throws ServletException { // Put your code here }
}對應的請求檔案：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <title>index.html</title>
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="this is my page">
<!--<link rel="stylesheet" type="text/css" href="./styles.css">-->
</head>
<body> <form action="./servlet/FileUpload" method="post" enctype="multipart/form-data" name="form1"> <input type="file" name="file"> <input type="submit" name="Submit" value="upload"></form> <form action="./servlet/HelloWord" method="post"> <input type="submit"/> </form> <form name="uploadform" method="POST" action="./servlet/FileUpload" ENCTYPE="multipart/form-data">
<table border="1" width="450" cellpadding="4" cellspacing="2" bordercolor="#9BD7FF">
<tr><td width="100%" colspan="2">
檔案1：<input name="x" size="40" type="file">
</td></tr>
<tr><td width="100%" colspan="2">
檔案2：<input name="y" size="40" type="file">
</td></tr>
<tr><td width="100%" colspan="2">
檔案3：<input name="z" size="40" type="file">
</td></tr>
</table>
<br/><br/>
<table>
<tr><td align="center"><input name="upload" type="submit" value="開始上傳"/></td></tr>
</table>
</form>
</body></html>註：該代碼由部分來自網上！
