Send email with Seam 3 Mail and JMS
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Join For FreeSeam 3 Mail module provides a simple API to use Java Mail API to send email messages.
Basic Configuration
Assume you have already created a Maven-based Java EE 6 application.
Add seam mail dependency to your pom.xml file.
<dependency> <groupId>org.jboss.seam.mail</groupId> <artifactId>seam-mail-api</artifactId> <scope>compile</scope> </dependency> <dependency> <groupId>org.jboss.seam.mail</groupId> <artifactId>seam-mail</artifactId> <scope>compile</scope> </dependency>
Add basic mail configuration in your META-INF/seam-beans.xml.
<mail:MailConfig serverHost="smtp.gmail.com" serverPort="587" auth="true" enableTls="true" username="<your gmail account>" password="<your password>"> <ee:modifies /> </mail:MailConfig>
In your Java code, inject MailMessage and Session.
@Inject private transient Instance<MailMessage> mailMessage; @Inject private transient Instance<Session> session;
MailMessage is provided by Seam3 module, it is a fluid API to build message object and send message. Session is from the standard Java Mail API.
MailMessage msg = mailMessage.get(); msg.subject("test subject") .from("test@test.com") .to("user@test.com") .send();
Everything works well.
But if you try to send an email from jsf pages, the page will be blocked when the email is being sent.
EJB 3.1 provides a simple way to execute asynchronous action. You can simply create a @Stateless EJB and put the logic in a @Asynchronous method. But unfortunately when you try to use @Asynchronous and CDI together, it does not work.
JMS provides standard asynchronous processing capability for Java EE, Seam3 also includes a JMS module.
Send email asynchronously with JMS
Seam 3 also provides a JMS module which simplify JMS and CDI integration, we can utilize JMS to process the asynchronous work.
Configure the JMS connection factory in your META-INF/seam-beans.xml.
<jmsi:JmsConnectionFactoryProducer> <ee:modifies /> <jmsi:connectionFactoryJNDILocation> java:/ConnectionFactory </jmsi:connectionFactoryJNDILocation> </jmsi:JmsConnectionFactoryProducer>
Create a standard JMS listener to handle JMS message.
@MessageDriven(....) public class MailProcessorMDB extends MessageListener { @EJB MailProcessor processor; public void send()...// @Override protected void onMessage(Message _msg) throws JMSException { if (log.isDebugEnabled()) { log.debug("call handleMessage..."); } ObjectMessage objMessage = (ObjectMessage) _msg; EmailMessage mailMessage = (EmailMessage) objMessage.getObject(); processor.send(mailMessage); } }
MailProcessor is a @Stateless EJB which is use for sending mail.
When a message is arrived, the listener will call MailProcessor to process email.
Use an interface to observe the CDI event and route it to the JMS queue.
@Outbound public void mapStatusToQueue(@Observes @NoneBlocking EmailMessage message, @JmsDestination(jndiName = "java:/queue/test") Queue q);
In the presentation layer, fire an event directly. The event object will be routed as the payload of JMS message automatically.
messageEventSrc.fire(message);
Run the project
I assume you have installed the latest Oracle JDK 7, JBoss AS 7.1.1.Final and Apache Maven 3.0.4.
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Check out the complete codes from github.com.
git clone git://github.com/hantsy/seam3-mail-demo.git
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Start JBoss AS with standalone full profile which includes JMS support.
<JBOSS_HOME>\bin\standalone.bat --server-config=standalone-full.xml
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Deploy the application into the running JBoss AS.
mvn clean package jboss-as:deploy
Open your browser and go to http://localhost:8080/seam3-mail-demo.
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