CapMailSender
+ host+ port+ username+ password+ timeout
+ init(properties)+ send(params):
MailSenderContext
+ get(params):MailSender+ limited(params)
MailSender
+ init(Properties)+ send(params):
AliSMTPMailSender
+ accessKey+ accessSecurity+ from
MailSendService
+ MailSenderContext
+ send(params)
MailSenderFactoryMethod
+ operation1(ENUM):MailSender
ENUM
SendCloudMailSender
+ apiUser+ apiKey+ from
