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：盡管有的資料解釋是commons-fileupload-1.0-beta.jar和commons-beanutils.jar，通過調試的結果
顯示并不是需要commons-beanutils.jar文件，而是由于在parseRequest(request)的類有關繼承于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。因此需要導入該包。否則就出
classNotFound：.DeferredFileOutputStream的錯誤。
2）由于涉及文件，就涉及到文件系統。然而在java或應用服務器中對于文件系統的訪問，就有一定的安全策略。
需要將下列權限添加到您應用程序服務器的安全策略文件中：
permission java.io.FilePermission "<<ALL FILES>>", "read,write,delete";
具體是添加到.."bea"weblogic81"server"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.InvocationTargetException
at
org.apache.commons.fileupload.FileUpload.createItem(FileUpload.java:615)
at
org.apache.commons.fileupload.FileUpload.parseRequest(FileUpload.java:474)
at
org.apache.commons.fileupload.FileUpload.parseRequest(FileUpload.java:355)
....
3）對于不同的服務器，在調試的過程中會出各種不一樣的結果。這個與具體的服務器有關。
4）由于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）。通過對最新的幫助文檔和網上的資料寫了一個標準的程序如下：
fileUpload（servlet）文件：
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;
/**
* @author gaolong1
*
* TODO 要更改此生成的類型注釋的模板，請轉至
* 窗口 － 首選項 － Java － 代碼樣式 － 代碼模板
*/
public class FileUpload extends HttpServlet {
/**
* Destruction of the servlet. <br>
*/
private String uploadPath = "D:""share""05_Servlet_JSP""apache-tomcat-5.5.17""webapps""drp1.4""images""item"""; // 用于存放上傳文件的目錄
private File tempPath =new File("D:""addnetFile""tmp"""); // 用于存放臨時文件的目錄
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
//內存中可以存儲數據的最大值(以字節為單位)
factory.setSizeThreshold(4096);
// the location for saving data that is larger than getSizeThreshold()
//設置文件的大小,如果大于SizeThreshold，則存到臨時目錄里
factory.setRepository(tempPath);
ServletFileUpload upload = new ServletFileUpload(factory);
// maximum size before a FileUploadException will be thrown
// 最大上傳文件，單位字節
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，過濾路徑取文件名
String regExp=".+""""(.+)$";
// 過濾掉的文件類型
String[] errorType={".exe",".com",".cgi",".asp"};
Pattern p = Pattern.compile(regExp);
String itemNo = "";
while (iter.hasNext()) {
FileItem item = (FileItem)iter.next();
//從文件域的表單信息中拿到從jsp頁面傳過來的itemNo,注意FileItem拿到itemNo方式;
if(item.isFormField()){
if(item.getFieldName().equals("itemNo")){
itemNo = item.getString();
}
}
//忽略其他不是文件域的所有表單信息
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{
// 保存上傳的文件到指定的目錄
// 在下文中上傳文件至數據庫時，將對這里改寫
item.write(new File(uploadPath + itemNo + ".gif"));
res.sendRedirect("../basedata/item_upload.jsp?itemNo=" + itemNo);
//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);
}
// 保存上傳的文件到指定的目錄
// 在下文中上傳文件至數據庫時，將對這里改寫
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
}
}
對應的請求文件：
注意，如果上傳需要在
<form name="uploadform" method="POST" action="./servlet/FileUpload" ENCTYPE="multipart/form-data">
</form>
|
html表單中加入ENCTYPE="multipart/form-data"，method設置為post(因為要上傳圖片),如：
<!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">
文件1：<input name="x" size="40" type="file">
</td></tr>
<tr><td width="100%" colspan="2">
文件2：<input name="y" size="40" type="file">
</td></tr>
<tr><td width="100%" colspan="2">
文件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>
注：該代碼部分來自網上！
dm520