Provides a service to send email messages on behalf of administrators or authenticated users, also accessible via a JavaMail interface. Receiving messages is not supported via the JavaMail API but is supported via an HTTP interface.
This low-level API is intended primarily for framework authors. For application developers we
 provide a custom javax.mail.Transport that allows the standard javax.mail
 interface to be used to send emails. No special configuration is required to send emails via this
 interface.
The com.google.appengine.api.mail.MailService.Message class represents a message, including sender and recipient information, and possibly attachments as com.google.appengine.api.mail.MailService.Attachment objects. These can be independently created via their respective constructors.
Sending a message requires a com.google.appengine.api.mail.MailService object, created
 by the com.google.appengine.api.mail.MailServiceFactory. Messages are sent
 asynchronously, so the MailService methods will
 always succeed immediately. Any errors in the mail message will be returned to the sender's
 address as "bounce" messages.
See Also: JavaMail API, com.google.appengine.api.mail.MailService, The Mail Java API in the  Google App Engine Developer's Guide
Classes
BounceNotificationParser
The BounceNotificationParser parses an incoming HTTP request into
 a description of a bounce notification.