如何从HttpServletRequest中获取图片
客户端提交一个图片到一个servlet，从这个servlet中怎么获取到上传的图片？代码如下：
客户端：
<form id="form1" name="form1" action="upload.action" method="post" enctype="multipart/form-data">
<input type="file" name="f" id="f" />
<input type="submit" name="s" id="s" value="提交" />
</form>

upload.action：
public class OImg extends HttpServlet {
  public void doPost(HttpServletRequest req, HttpServletResponse res)
  throws ServletException, IOException {
System.out.println("ContentLength: " + req.getContentLength());
  //？？？？？？？？怎么获取上传的图片？？
  }
}

------解决方案--------------------
用smartUpload 之类的上传组件！

去google 搜索
smartupload

http://dev.csdn.net/develop/article/18/18987.shtm