Flex+java實現文件上傳

用了兩天時間學習了下Flex和java配合實現文件上傳，找了個小例子。前端當然是flex，後臺使用servlet，把代碼貼上來，備忘吧：

 

FileUpload.java:

import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.util.Iterator; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; @SuppressWarnings("serial") public class FileUpload extends HttpServlet { //定義文件上傳的路徑 private String uploadPath = "d://a//"; private int maxPostSize = 100*1024*1024; public FileUpload() { super(); } public void destroy() { super.destroy(); } @SuppressWarnings("unchecked") protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException,IOException { System.out.println("Access!"); response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); out.print("已連接上!"); //保存文件到服務器中 DiskFileItemFactory factory = new DiskFileItemFactory(); factory.setSizeThreshold(4096); ServletFileUpload upload = new ServletFileUpload(factory); upload.setSizeMax(maxPostSize); try { List fileItems = upload.parseRequest(request); Iterator iter = fileItems.iterator(); while(iter.hasNext()) { FileItem item = (FileItem)iter.next(); if(!item.isFormField()) { String name = item.getName(); System.out.println(name); try { item.write(new File(uploadPath+name)); } catch(Exception e) { e.printStackTrace(); } } } } catch(FileUploadException e) { e.printStackTrace(); System.out.println(e.getMessage()+"結束"); } } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } }

 

FileUpload.mxml

<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" creationComplete="init()"> <mx:Script> <![CDATA[ import flash.net.FileReference; import mx.controls.Alert; import mx.events.CloseEvent; import flash.events.*; private var file:FileReference; private function init():void { Security.allowDomain("*"); file = new FileReference(); file.addEventListener(ProgressEvent.PROGRESS, onProgress); file.addEventListener(Event.SELECT, onSelect); file.addEventListener(Event.COMPLETE, completeHandle); } private function completeHandle(event:Event):void { Alert.show("恭喜你，上傳成功"); } private function upload():void { var imageTypes:FileFilter = new FileFilter("Images (*.jpg, *.jpeg, *.png)","*.jpg;*.jpeg;*.png"); var allTypes:Array = new Array(imageTypes); file.browse(allTypes); //file.browse(); } private function onSelect(e:Event):void { Alert.show("上傳 " + file.name + " (共 " + Math.round(file.size) + " 字節)?","確認上傳",Alert.YES|Alert.NO,null,proceedWithUpload); } private function onProgress(e:ProgressEvent):void { lbProgress.text = "已上傳 "+e.bytesLoaded + " 字節，共 "+e.bytesTotal+" 字節"; var proc:uint = e.bytesLoaded/e.bytesTotal*100; bar.setProgress(proc,100); bar.label = "當前進度： "+" "+proc + "%"; } private function proceedWithUpload(e:CloseEvent):void { if(e.detail == Alert.YES) { var request:URLRequest = new URLRequest("http://localhost:8080/FileUpload/servlet/FileUpload"); try { file.upload(request); } catch(error:Error) { Alert.show("上傳失敗"); } } } ]]> </mx:Script> <mx:Canvas width="100%" height="100%" x="10" y="170" fontSize="12"> <mx:VBox width="100%" horizontalAlign="center"> <mx:Label id="lbProgress" text="上傳" /> <mx:ProgressBar id="bar" labelPlacement="bottom" themeColor="#F20D7A" minimum="0" visible="true" maximum="100" label="當前進度： 0%" direction="right" mode="manual" width="200" /> <mx:Button label="上傳文件" click="upload()" /> </mx:VBox> </mx:Canvas> </mx:Application>

 

配置到tomcat上的時候，要在web-inf/lib裏面要加入連個包：

1. commons-fileupload-1.2.1.jar
2. commons-io-1.4.jar

這兩個包在網上很容易下載到。加入包以後要修改web.xml，在跟下加入下面servlet聲明：

<servlet> <servlet-name>FileUpload</servlet-name> <servlet-class>FileUpload</servlet-class> </servlet> <servlet-mapping> <servlet-name>FileUpload</servlet-name> <url-pattern>/servlet/FileUpload</url-pattern> </servlet-mapping>

我的文件是上傳到D盤的a文件夾，要確保該目錄存在。上傳個圖片試試吧！