I am trying to get emails from Microsoft Exchange server using EWSJ API which in terms uses Exchange Web Services; but I would like to know; will it be fast to fetch emails using IMAP?
Since we have GWT we cannot directly connect to Exchange from client side in either case; we want to minimize the turn around time of getting emails on server side and then passing those to client side using serialized POJOs.
From my experience IMAP seems to be the fastest at the moment. I used it once to create a small program that could fetch emails from GMail. A bonus is that you can mark emails as "read" from the IMAP interface.
If I had to choose I'd go for IMAP.
Apache Hupa is a subproject of the Apache James project, and it is a webmail client developed with GWT, it uses a server side able to get messages from any IMAP enabled server (it uses the javax.mail api).
Although you can use directly Hupa to read and send emails using your email server (there is a properties file to define imap and smtp parameters), in your case you could get the server side to connect to your servers and use any GWT ajax mechanism to get the messages like Hupa client side does.
Here you have a live demo of Hupa.
