etf.org/rfc/rfc2177.txt">RFC 2177), if supported by the server, to enter idle mode so that the server can send unsolicited notifications of new messages arriving, etc. without the need for the client to constantly poll the server. Use an appropriate listener to be notified of new messages or other events. When another thread (e.g., the listener thread) needs to issue an IMAP comand for this folder, the idle mode will be terminated and this method will return. Typically the caller will invoke this method in a loop.
The mail.imap.minidletime property enforces a minimum delay before returning from this method, to ensure that other threads have a chance to issue commands before the caller invokes this method again. The default delay is 10 milliseconds.
@exception MessagingException if the server doesn't support theIDLE extension
@exception IllegalStateException if the folder isn't open
@since JavaMail 1.4.1