gwt 上传文件

gwt使用apache-commons-fileUpload,轻松实现文件上传，图片上传等功能。

 1.gwt 前端页面（可以做成组建，供各个模块调用）

FormPanel formPanel  = new FormPanel();  
formPanel.setAction("/uploadImage");  
  
formPanel.setEncoding(FormPanel.ENCODING_MULTIPART);  
formPanel.setMethod(FormPanel.METHOD_POST);  
  
FlowPanel panel = new FlowPanel();  
formPanel.setWidget(panel);  
  
FileUpload fileUpload = new FileUpload();  
fileUpload.setName("file");  
panel.add(fileUpload);  
ok,formpanel触发sumbit即可。下面便是servlet端的实现。           
 
2.servlet端
FileItemFactory factory = new DiskFileItemFactory();     
ServletFileUpload upload = new ServletFileUpload(factory);     
    
List items = null;     
    
try {     
    items = upload.parseRequest(request);     
} catch (FileUploadException ex) {     
    throw new ServletException(ex);     
}     
    
Iterator iter = items.iterator();     
    
while (iter.hasNext()) {     
    FileItem item = (FileItem) iter.next();     
    if (item.isFormField() == false) {     
         //获得byte数组  
        byte[] bytes = item.get();  
        //或直接保存成文件  
        File file = new FIle("D:/temp",item.getName());      
        item.write(file);//直接保存文件          
    }     
}