java语言写的一个简单的邮件收发系统 但由于条件的限制，只能针对特定的邮件系统进行发送，但能对决大多数邮件系统进行收邮件功能，只要按照提示一步一步做-write a simple mail system because of the limitations, only specific mail system sent, but the majority will mail system between the resumption of mail, as long as they do