java文件上传--基于ajaxFileUpload+struts2

jQuery插件ajaxFileUpload可以实现ajax文件上传，使用非常简单。

注：以下的代码是在项目的基础上进行开发。css样式文件、包路径等未做修改。

1、 ajaxFileUpload文件下载地址http://www.phpletter.com/Demo/AjaxFileUpload-Demo/

2、自行引入jquery.js、ajaxFileUpload.js文件

jsp核心代码：

<script type="text/javascript">  function fileUpload() { $.ajaxFileUpload( {  url : 'admin/fileAction.do',//用于文件上传的服务器端请求地址  secureuri : false,          //一般设置为false  fileElementId : 'file',     //文件上传空间的id属性  <input type="file" id="file" name="file" />  dataType : 'json',          //返回值类型 一般设置为json  success : function(data, status) {   $("#downImg").show();   //待上传成功后 显示下载按钮   $("#downImg").attr("href","admin/downloadImage.do?filePath="+data.filePath);   $("#showImg").attr("src","admin/redImage.do?path=" + data.filePath);  } })  }</script><table class="editTable">   <tr> <td colspan="4">  <img id="showImg" alt="" src="">  <a id="downImg" style="display: none" href="">下载</a>  </td>   </tr>   <tr> <td class="title">  上传图片: </td> <td colspan="3">  <input type="file" id="file" name="file" onchange="fileUpload();"> </td>   </tr></table>

public class AjaxFileUploadAction extends WebSupport { private File file;            //文件 private String fileFileName;  //文件名  private String filePath;      //文件路径 private InputStream inputStream; /**  * 图片上传  *   * @return  */ public String fileUpload() {  String path = ServletActionContext.getServletContext().getRealPath("/upload");  File file = new File(path); // 判断文件夹是否存在,如果不存在则创建文件夹  if (!file.exists()) {   file.mkdir();  }  try {    if (this.file != null) {   File f = this.getFile();   String fileName = java.util.UUID.randomUUID().toString(); // 采用时间+UUID的方式随即命名   String name = fileName+ fileFileName.substring(fileFileName.lastIndexOf(".")); // 保存在硬盘中的文件名   FileInputStream inputStream = new FileInputStream(f);   FileOutputStream outputStream = new FileOutputStream(path+ "\" + name);   byte[] buf = new byte[1024];   int length = 0;   while ((length = inputStream.read(buf)) != -1) {    outputStream.write(buf, 0, length);   }   inputStream.close();   outputStream.flush();   //文件保存的完整路径  比如：D:tomcat6webappseserver\uploada0be14a1-f99e-4239-b54c-b37c3083134a.png   filePath = path+"\"+name;    }  } catch (Exception e) {   e.printStackTrace();  }  return SUCCESS; } /**  * 用于图片页面显示  *   * @return  */ public String readImg() {  try {   inputStream = new FileInputStream(new File(getRequest().getParameter("path")));  } catch (FileNotFoundException e) {   e.printStackTrace();  }  return SUCCESS; } /**  * 图片下载  * @return  */ public String download() {        String path = filePath;        HttpServletResponse response = ServletActionContext.getResponse();        try {            // path是指欲下载的文件的路径。            File file = new File(path);            // 取得文件名。            String filename = file.getName();            // 取得文件的后缀名。            String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();            // 以流的形式下载文件。            InputStream fis = new BufferedInputStream(new FileInputStream(path));            byte[] buffer = new byte[fis.available()];            fis.read(buffer);            fis.close();            //清空response            response.reset();            //设置response的Header            String filenameString = new String(filename.getBytes("gbk"),"iso-8859-1");            response.addHeader("Content-Disposition", "attachment;filename=" + filenameString);            response.addHeader("Content-Length", "" + file.length());            OutputStream toClient = new BufferedOutputStream(response.getOutputStream());            response.setContentType("application/octet-stream");            toClient.write(buffer);            toClient.flush();            toClient.close();        } catch (IOException ex) {            ex.printStackTrace();        }        return null;    } public File getFile() {  return file; } public void setFile(File file) {  this.file = file; } public String getFileFileName() {  return fileFileName; } public void setFileFileName(String fileFileName) {  this.fileFileName = fileFileName; } public String getFilePath() {  return filePath; } public void setFilePath(String filePath) {  this.filePath = filePath; } public InputStream getInputStream() {  return inputStream; } public void setInputStream(InputStream inputStream) {  this.inputStream = inputStream; } private static final Logger log = Logger   .getLogger(AjaxFileUploadAction.class); private static final long serialVersionUID = 1L;}

<struts>    <package name="struts_Ajax_code" extends="json-default">        <!-- 文件上传 -->         <action name="fileAction" class="com.bk.eserver.web.action.AjaxFileUploadAction" method="fileUpload">             <result type="json" name="success">                  <param name="contentType">text/html</param>             </result>        </action>    </package>     <package name="struts_Jsp_code" extends="struts-default">        <!-- 图片读取 -->         <action name="redImage" class="com.bk.eserver.web.action.AjaxFileUploadAction" method="readImg">             <result type="stream">                  <param name="contentType">application/octet-stream</param>                   <param name="inputName">inputStream</param>                   <param name="contentDisposition">attachment;filename=${fileName}</param>                   <param name="bufferSize">4096</param>             </result>        </action>         <!-- 文件下载 -->         <action name="downloadImage" class="com.bk.eserver.web.action.AjaxFileUploadAction" method="download">             <result type="stream">                  <param name="contentType">application/octet-stream</param>                   <param name="inputName">inputStream</param>                   <param name="contentDisposition">attachment;filename=${fileName}</param>                   <param name="bufferSize">4096</param>             </result>        </action>    </package> </struts>