AJAX+JSF组件实现高性能的文件上载

public class UploadMultipartFilter implements Filter{ 

　public void doFilter(ServletRequest request，
ServletResponse response，FilterChain chain) 

　throws IOException， ServletException {

HttpServletRequest hRequest = (HttpServletRequest)request;

//检查是否我们在处理一个多部分请求

String contentHeader = hRequest.getHeader("content-type");

boolean isMultipart = ( contentHeader !
= null && contentHeader.indexOf("multipart/form-data") != -1); 

if(isMultipart == false){

　chain.doFilter(request，response);

}else{

　UploadMultipartRequestWrapper wrapper 
= new UploadMultipartRequestWrapper(hRequest);

　chain.doFilter(wrapper，response);

}

...

　}

public class UploadMultipartRequestWrapper 

extends HttpServletRequestWrapper{

　private Map＜String，String＞ formParameters;

　private Map＜String，FileItem＞ fileParameters;

　public UploadMultipartRequestWrapper(HttpServletRequest request) {

super(request);

try{

　ServletFileUpload upload = new ServletFileUpload();

　upload.setFileItemFactory(
new ProgressMonitorFileItemFactory(request));

　List fileItems = upload.parseRequest(request);

　formParameters = new HashMap＜String，String＞();

　fileParameters = new HashMap＜String，FileItem＞();

　for(int i=0;i＜fileItems.size();i++){

FileItem item = (FileItem)fileItems.get(i);

if(item.isFormField() == true){

　formParameters.put(item.getFieldName()，item.getString());

}else{

　fileParameters.put(item.getFieldName()，item);

　request.setAttribute(item.getFieldName()，item);

}

　}

　}catch(FileUploadException fe){

//请求时间超过-用户可能已经转到另一个页面。

//作一些记录

//...

　}

　...