文件上传两种方法

第一种文件上传方式，用到commons-fileupload.jar,commons-io.jar

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

HttpSession session = request.getSession();

session.setAttribute("SESSIONID",session.getId());

FileItemFactory factory = new DiskFileItemFactory();

ServletFileUpload upload = new ServletFileUpload(factory);

try {

List<FileItem> items = upload.parseRequest(request);

Iterator<FileItem> itr = items.iterator();

while(itr.hasNext()){

FileItem item=(FileItem)itr.next();

String fileName=item.getName();

if(fileName!=null){

File fullFile=new File(item.getName());

File savedFile=new File("d:/uploads",fullFile.getName());

item.write(savedFile);

}

}

} catch (FileUploadException e) {

e.printStackTrace();

} catch (Exception e) {

e.printStackTrace();

}

}

第二种文件上传方式，这里用到cos组件方式上传，需要导入cos.jarn,不过srping中的multipart包已经有了....

public ModelAndView uploadImageCoCustQuiz(HttpServletRequest request,HttpServletResponse response) throws Exception {
System.out.print("我进到上传文件的方法了！！！！");

MultipartFile mf = null;
File file = null;
String upLoadFilePath = null;
String fileName=null;
JSONObject jo = new JSONObject();
try{

final String path = "D:/uploadFile/";

final File dirPath = new File(path);
if(!dirPath.exists())
dirPath.mkdirs();

//让request能转换成multipart...对象,那么ext上传文件一定要设置 某个form.getForm().fileUpload = true或者设置

formpanel的enctype : 'multipart/form-data',

MultipartResolver resolver = new CommonsMultipartResolver();
if(resolver.isMultipart(request)){

final MultipartHttpServletRequest mhs = (MultipartHttpServletRequest) request;

//只要你前台的文本框是文件类型的,不管你有没有上传文件,后台依然有得到流,只是应该说这个流是否为无效流,如果是无效流则

jdbctemplate插入或者更新时就是插入null了..

//只要前台的文本框为文件类型,不管有没有上传文件,mf都可以得到,不会为空
mf = mhs.getFile("uploadFile");

final String uploadFileName = mf.getOriginalFilename();

//mf.getInputStream() 得到文件输入流
if(uploadFileName!=null || uploadFileName!="")
{
final String objStr = uploadFileName.substring(uploadFileName.lastIndexOf(".")).trim();
//String uploadFileNameStr = uploadFileName.substring(0,uploadFileName.indexOf(".")).trim();
fileName = "1" + objStr;
}

//fileName.trim();
upLoadFilePath = path+uploadFileName;
file = new File(upLoadFilePath);
mf.transferTo(file);
//上传文件完毕

} catch (Exception e) {
System.out.print("上传文件方法中出现异常。。。。。。。。。。。。。。。。。。。");
}
}else{
System.out.println("连文件都不是!!!");
}

jo.put("success", true);

response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
out.print(jo.toString());
out.flush();
out.close();
return null;
}

cos组件的multipartRequest的8个构造方法和8个方法

在Cos组件中，MultipartRequest类主要负责文件上传的处理。MultipartRequest有8个构造函数：

1.Public MultipartRequest ( HttpServletRequest request, String saveDirectory,) throws IOException



2.Public MultipartRequest ( HttpServletRequest request, String saveDirectory, int maxPostSize) throws IOException



3.Public MultipartRequest ( HttpServletRequest request, String saveDirectory, int maxPostSize, FileRenamePolicy policy) throws IOException



4.Public MultipartRequest ( HttpServletRequest request, String saveDirectory, int maxPostSize, String encoding) throws IOException



5.Public MultipartRequest ( HttpServletRequest request, String saveDirectory, int maxPostSize, String encoding, FileRenamePolicy policy) throws IOException



6.Public MultipartRequest ( HttpServletRequest request, String saveDirectory, String encoding) throws IOException



7.Public MultipartRequest ( HttpServletRequest request, String saveDirectory) throws IOException



8.Public MultipartRequest ( HttpServletRequest request, String saveDirectory, int maxPostSize) throws IOException



前6种构造函数都是用来专门处理HTTP协议的，saveDirectory是上传文件要存储在服务器端的目录名称；maxPostSize是用来限制用户上传文件大小的，若超过maxPostSzie，会产生IOException，默认上传文件大小是1MB；encoding可以设定用何种编码方式来上传文件名称，可以解决中文问题。

MultipartRequest类工具有8种方法，利用这些方法，我们可以取得请求的相关信息：

Public Enumeration getParameterNames()　可以取得请求参数的名称

public String getParameter(String name)　　此方法传回参数为name的值

public String[] getParameterValues(String name)　此方法主要用在取得当一指定参数具有多个值时，它会传回String的数组

public Enumeration getFileName()　传回所有文件输入类型的名称

public String getFilesystemNames(String name)　用此方法得到上传文件的真正的文件名，这里的name指文件输入类型的名称

public String getContentType(String name)　此方法得到上传文件的内容类型

public File getFile(String name)　此方法得到一个文件对象，代表储存在服务器上的name文件

public String getOriginalFileName(String name)　返回文件在修改政策有效之前的文件名