如何获取file 文件上传是的参数

package servlet

import java.io.File

import java.io.IOException

import java.util.Iterator

import java.util.List

import javax.servlet.ServletConfig

import javax.servlet.ServletContext

import javax.servlet.ServletException

import javax.servlet.http.HttpServlet

import javax.servlet.http.HttpServletRequest

import javax.servlet.http.HttpServletResponse

import javax.servlet.http.HttpSession

import org.apache.commons.fileupload.FileItem

import org.apache.commons.fileupload.disk.DiskFileItemFactory

import org.apache.commons.fileupload.servlet.ServletFileUpload

public class upload extends HttpServlet {

/**

*

*/

private static final long serialVersionUID = 2654821751525075943L

private ServletContext sc

private String savePath

/**

* The doGet method of the servlet. <br>

*

* This method is called when a form has its tag value method equals to get.

*

* @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 doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

doPost(request,response)

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

String username=""

request.setCharacterEncoding("utf-8")

DiskFileItemFactory factory=new DiskFileItemFactory()

ServletFileUpload upload=new ServletFileUpload(factory)//专门用来完成文件上传的类

try {

List items=upload.parseRequest(request)//解析请求，返回一个存储了所有表单元素的集合

Iterator it=items.iterator()

while(it.hasNext()){

FileItem item=(FileItem)it.next()

if(item.isFormField()){//如果是普通的文本信息，返回true

username=item.getString("utf-8")

}else{

if(item.getName()!=null&&!item.getName().equals("")){//防止抛出空指针，判断一下是否为空

System.out.println("上传文件的大小："+item.getSize())

System.out.println("上传文件的类型："+item.getContentType())

System.out.println("上传文件的名称："+item.getName())

File temp=new File(item.getName())

File file=new File(sc.getRealPath("/")+savePath,temp.getName())

item.write(file)

HttpSession hs=request.getSession()

hs.setAttribute("path", item.getName())

request.setAttribute("msg", "上传文件成功了")

}else{

request.setAttribute("msg", "上传文件失败了")

}

}

}

}catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace()

request.setAttribute("msg", "上传文件失败了")

}

request.getRequestDispatcher("/result.jsp?username="+username).forward(request, response)

}

/**

* 重写init方法

*/

public void init(ServletConfig config){

savePath=config.getInitParameter("savePath")//获取初始化的参数

sc=config.getServletContext()//获取ServletContext对象，并赋给sc

}

}

[align=right][align=left]DiskFileItemFactory factory=new DiskFileItemFactory()

String path=request.getRealPath("/upload")

System.out.println(path)

factory.setRepository(new File(path))

factory.setSizeThreshold(1024*1024)

ServletFileUpload upload=new ServletFileUpload(factory)

try{

List<FileItem>ls=upload.parseRequest(request)

for (FileItem item : ls) {

if(item.isFormField()){

String name=item.getFieldName()

String value=item.getString("gbk")

request.setAttribute(name, value)

}else{

String name=item.getFieldName()

String value=item.getName()

int start=value.lastIndexOf("\\")

String fileName=value.substring(start+1)

System.out.println(fileName)

request.setAttribute(name, fileName)

Encoding en=new Encoding()

//item.write(new File(path,fileName))

OutputStream os=new FileOutputStream(new File(path,fileName))

InputStream is=item.getInputStream()

byte [] bt=new byte[400]

int length=0

while((length=is.read(bt))>0){

os.write(bt, 0, length)

}

os.close()

is.close()

}

}

}catch (Exception e) {

e.printStackTrace()

}[/align][/align]

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