String senderName = sender == null ? null : sender.getDisplayName();
parameters.put(TKEY_SENDER, senderName == null ? UNKNOWN_USER_NAME : senderName);
String senderSign = sender == null ? null : sender.getSign();
parameters.put(TKEY_SENDER_SIGN, senderSign == null ? "" : senderSign);
if(recipients != null && recipients.size() == 1) {
User recipient = recipients.iterator().next();
String recipientName = recipient.getDisplayName();
parameters.put(TKEY_RECIPIENT, recipientName == null ? UNKNOWN_USER_NAME : recipientName);
}
String body = templateGenerator.generate(TEMPLATE_PREFIX + templatePath, parameters, localeService.getCurrentLocale());
send(recipients, sender, subject, body);