HyperPool is a 100% pure Java project for network services management. TCP (HTTP/1.1, HTTPS, FTP, SMTP, POP3), UDP and SOCKS5 protocols support. Configurations: proxy, web server, mail server, download manager, port mapping.
Mailster is a project aimed at testing software mail capabilities. It provides a mail server container to test emails sent by your apps without rewriting your application code.