Spring Integration provides support for outbound email with the
MailSendingMessageHandler. It delegates to a configured instance of Spring's
JavaMailSender mailSender = (JavaMailSender) context.getBean("mailSender"); MailSendingMessageHandler mailSendingHandler = new MailSendingMessageHandler(mailSender);
MailSendingMessageHandler has various mapping strategies that use Spring's
MailMessage abstraction. If the received Message's payload is already
MailMessage instance, it will be sent directly.
Therefore, it is generally recommended to precede this
consumer with a Transformer for non-trivial MailMessage construction requirements. However, a few simple
Message mapping strategies are supported out-of-the-box. For example, if the message payload is a byte array,
then that will be mapped to an attachment. For simple text-based emails, you can provide a String-based
Message payload. In that case, a MailMessage will be created with that String as the text content. If you
are working with a Message payload type whose toString() method returns appropriate mail text content, then
consider adding Spring Integration's ObjectToStringTransformer prior to the outbound
Mail adapter (see the example within Section 5.1.2, “Namespace support for Transformer - <transformer> Element” for more detail).
The outbound MailMessage may also be configured with certain values from the
MessageHeaders. If available, values will be mapped to the outbound mail's
properties, such as the recipients (TO, CC, and BCC), the from/reply-to, and the subject. The header names are
defined by the following constants:
MailHeaders.SUBJECT MailHeaders.TO MailHeaders.CC MailHeaders.BCC MailHeaders.FROM MailHeaders.REPLY_TO
Spring Integration also provides support for inbound email with the
MailReceivingMessageSource. It delegates to a configured instance of Spring
MailReceiver interface, and there are two implementations:
ImapMailReceiver. The easiest way to
instantiate either of these is by passing the 'uri' for a Mail store to the receiver's constructor. For example:
MailReceiver receiver = new Pop3MailReceiver("pop3://usr:[email protected]/INBOX");
Another option for receiving mail is the IMAP "idle" command (if supported by the mail server you are using).
Spring Integration provides the
ImapIdleChannelAdapter which is itself a Message-producing
endpoint. It delegates to an instance of the
ImapMailReceiver but enables asynchronous
reception of Mail Messages. There are examples in the next section of configuring both types of inbound Channel
Adapter with Spring Integration's namespace support in the 'mail' schema.
Spring Integration provides a namespace for mail-related configuration. To use it, configure the following schema locations.
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mail="http://www.springframework.org/schema/integration/mail" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/integration/mail http://www.springframework.org/schema/integration/mail/spring-integration-mail-2.0.xsd">
To configure an outbound Channel Adapter, provide the channel to receive from, and the MailSender:
<mail:outbound-channel-adapter channel="outboundMail" mail-sender="mailSender"/>
Alternatively, provide the host, username, and password:
<mail:outbound-channel-adapter channel="outboundMail" host="somehost" username="someuser" password="somepassword"/>
|Keep in mind, as with any outbound Channel Adapter, if the referenced channel is a PollableChannel, a <poller> sub-element should be provided with either an interval-trigger or cron-trigger.|
To configure an inbound Channel Adapter, you have the choice between polling or event-driven (assuming your mail server supports IMAP IDLE - if not, then polling is the only option). A polling Channel Adapter simply requires the store URI and the channel to send inbound Messages to. The URI may begin with "pop3" or "imap":
<int-mail:inbound-channel-adapter id="imapAdapter" store-uri="imaps://[username]:[password]@imap.gmail.com/INBOX" java-mail-properties="javaMailProperties" channel="recieveChannel" should-delete-messages="true" should-mark-messages-as-read="true" auto-startup="true"> <int:poller max-messages-per-poll="1" fixed-rate="5000"/> </int-mail:inbound-channel-adapter>
If you do have IMAP idle support, then you may want to configure the "imap-idle-channel-adapter" element instead. Since the "idle" command enables event-driven notifications, no poller is necessary for this adapter. It will send a Message to the specified channel as soon as it receives the notification that new mail is available:
<int-mail:imap-idle-channel-adapter id="customAdapter" store-uri="imaps://[username]:[password]@imap.gmail.com/INBOX" channel="recieveChannel" auto-startup="true" should-delete-messages="false" should-mark-messages-as-read="true" java-mail-properties="javaMailProperties"/>
... where javaMailProperties could be provided by creating and populating
java.utils.Properties object. For example via util namespace
provided by Spring.
<util:properties id="javaMailProperties"> <prop key="mail.imap.socketFactory.class">javax.net.ssl.SSLSocketFactory</prop> <prop key="mail.imap.socketFactory.fallback">false</prop> <prop key="mail.store.protocol">imaps</prop> <prop key="mail.debug">false</prop> </util:properties>
In both configurations |
|When configuring a polling adapter (e.g., inbound-channel-adapter) should-mark-messages-as-read be aware of the protocol you are configuring to retrieve messages. For example POP3 does not support this flag which means setting it to either value will have no effect as messages will NOT be marked as read|
When using the namespace support, a header-enricher Message Transformer is also available. This simplifies the application of the headers mentioned above to any Message prior to sending to the Mail-sending Channel Adapter.
<mail:header-enricher subject="Example Mail" to="[email protected]" cc="[email protected]" bcc="[email protected]" from="[email protected]" reply-to="[email protected]" overwrite="false"/>