struts 2不能上传一个空文件？

Question

struts2是不是不能上传一个大小为0k的文件啊？
怎么解决这个问题？
[b]问题补充：[/b]
struts2的拦截器只能限制最大上传大小不能设置最小啊?
maximumSize 这个是最大的
最小的我没找到如何设置
[b]问题补充：[/b]
如果上传的文件大小是0K，到Action中的时候，进行文件拷贝的时候，会抛一个filenotfoundException.
但是我试过其他的系统的上传文件，比如说邮箱，我在附件上传中，上传一个0K的文件，发给另外一个人，另外一个人依然能获取这个文件，大小是0？
我就想知道人家是什么机制？

Answer 1

修改struts.multipart.parser常量的值为cos/pell

[quote]When not selecting any file to upload in a file input, Struts does not ignore the 0 byte file
returned by jakarta FileUpload.
This means that a file is injected in the action even if nothing was uploaded.

In webwork the check was done in the constructor of com.opensymphony.webwork.dispatcher.multipart.JakartaMultiPartRequest:

else if (item.getSize() == 0) {
log.warn("Item is a file upload of 0 size, ignoring");
}

In struts the parsing of the request moved from the constructor to a parse method but the
above check disappeared.

Additionally this behaviour is inconsistant with the "pell" implementation that ignores 0
byte files.

This message is automatically generated by JIRA.[/quote]