//得到文件?名   
String filename=file.getOriginalFilename();           
25.               
if(file.getSize()>0){                  
    try {   
        SaveFileFromInputStream(file.getInputStream(),"D:/",filename);   
    } catch (IOException e) {   
        System.out.println(e.getMessage());   
        return null;   
    }   
}else{   
    throw new Exception("上传失败：上传文件不能为?空");   
} 


public void SaveFileFromInputStream(InputStream stream,String path,String filename) throws IOException   {         
    FileOutputStream fs=new FileOutputStream( path + "/"+ filename);   
    byte[] buffer =new byte[1024*1024];   
    int bytesum = 0;   
    int byteread = 0;    
    while ((byteread=stream.read(buffer))!=-1){   
        bytesum+=byteread;   
        fs.write(buffer,0,byteread);   
        fs.flush();   
    }    
    fs.close();   
    stream.close();         
}