The Apache Java Enterprise Mail Server (a.k.a. Apache James) is a 100% pure Java SMTP and POP3 Mail server and NNTP News server. James is a complete and portable enterprise mail engine solution based on currently available open protocols.

James is also a mail application platform. We have developed a Java API to let you write Java code to process emails that we call the mailet API. A mailet can generate an automatic reply, update a database, prevent spam, build a message archive, or whatever you can imagine. A matcher determines whether your mailet should process an email in the server. The James project hosts the Mailet API, and James provides an implementation of this mail application platform API.