Method select

app/src/main/java/com/sun/mail/imap/IdleManager.java:234–285

Run the java.nio.channels.Selector#select select loop to poll each watched folder for events sent from the server.

()

     * to poll each watched folder for events sent from the server.
     */
    private void select() {
	die = false;
	try {
	    while (!die) {
		watchAll();
		logger.finest("IdleManager waiting...");
		int ns = selector.select();
		if (logger.isLoggable(Level.FINEST))
		    logger.log(Level.FINEST,
			"IdleManager selected {0} channels", ns);
		if (die || Thread.currentThread().isInterrupted())
		    break;

		/*
		 * Process any selected folders.  We cancel the
		 * selection key for any selected folder, so if we
		 * need to continue watching that folder it's added
		 * to the toWatch list again.  We can't actually
		 * register that folder again until the previous
		 * selection key is cancelled, so we call selectNow()
		 * just for the side effect of cancelling the selection
		 * keys.  But if selectNow() selects something, we
		 * process it before adding folders from the toWatch
		 * queue.  And so on until there is nothing to do, at
		 * which point it's safe to register folders from the
		 * toWatch queue.  This should be "fair" since each
		 * selection key is used only once before being added
		 * to the toWatch list.
		 */
		do {
		    processKeys();
		} while (selector.selectNow() > 0 || !toAbort.isEmpty());
	    }
	} catch (InterruptedIOException ex) {
	    logger.log(Level.FINEST, "IdleManager interrupted", ex);
	} catch (IOException ex) {
	    logger.log(Level.FINEST, "IdleManager got I/O exception", ex);
	} catch (Exception ex) {
	    logger.log(Level.FINEST, "IdleManager got exception", ex);
	} finally {
	    die = true;	// prevent new watches in case of exception
	    logger.finest("IdleManager unwatchAll");
	    try {
		unwatchAll();
		selector.close();
	    } catch (IOException ex2) {
		// nothing to do...
		logger.log(Level.FINEST, "IdleManager unwatch exception", ex2);
	    }
	    logger.fine("IdleManager exiting");
	}
    }

    /**
     * Register all of the folders in the queue with the selector,