Use mail

You can enable your J2EE applications to use mail resources with the JavaMail API. Using the JavaMail API, a code segment can be embedded in any Java 2 Enterprise Edition (J2EE) application component, such as an EJB or a servlet, allowing the application to send a message and save a copy of the mail to the Sent folder.The following is a code sample that you would embed in a J2EE application:

javax.naming.InitialContext ctx = new javax.naming.InitialContext();

   javax.mail.Session mail_session = (javax.mail.Session) ctx.lookup("java:comp/env/mail/MailSession3");
   MimeMessage msg = new MimeMessage(mail_session);

   msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse("bob@coldmail.net"));

   msg.setFrom(new InternetAddress("alice@mail.eedge.com"));

   msg.setSubject("Important message from eEdge.com");

   msg.setText(msg_text);

   Transport.send(msg);

 
   Store store = mail_session.getStore();

   store.connect();

   Folder f = store.getFolder("Sent");

   if (!f.exists()) f.create(Folder.HOLDS_MESSAGES);

   f.appendMessages(new Message[] {msg});

 

Overview

Procedure

1. Locate a resource through Java Naming and Directory Interface (JNDI). The J2EE specification considers a mail session instance as a resource, or a factory from which mail transport and store connections can be obtained. Do not hard code mail sessions (namely, fill up a Properties object, then use it to create a javax.mail.Session object). Instead, follow the J2EE programming model of configuring resources through the system facilities and then locating them through JNDI lookups.

   In the previous sample code, the line javax.mail.Session mail_session = (javax.mail.Session) ctx.lookup("java:comp/env/mail/MailSession3"); is an example of not hard coding a mail session and using a resource name located through JNDI. You can consider the lookup name, mail/MailSession3, as a soft link to the real resource.

2. Define resource references while assembling your application. You must define a resource reference for the mail resource in the deployment descriptor of the component, because a mail session is referenced in the JNDI lookup. Typically, you can use an assembly tool shipped with WebSphere Application Server.When you create this reference, be sure that the name of the reference matches the name used in the code. For example, the previous code uses java:comp/env/mail/MailSession3 in its lookup. Therefore the name of this reference must be mail/Session3, and the type of the resource must be javax.mail.Session. After configuration, the deployment descriptor contains the following entry for the mail resource reference:

   <resource-reference> 
   <description>description</description>  
   <res-ref-name>mail/MailSession3</res-ref-name>
   <res-type>javax.mail.Session</res-type>  
   <res-auth>Container</res-auth>    

3. Configure mail providers and sessions. The sample code references a mail resource, the deployment descriptor declares the reference, but the resource itself does not exist yet. Now you need to configure the mail resource that is referenced by your application component. Notice that the mail session you configure must have both its transport and mail access portions defined; the former required because the code is sending a message, the latter because it also saves a copy to the local mail store. When you configure the mail session, you need to specify a JNDI name. This is an important name for installing your application and linking up the resource references in your application with the real resources that you configure.

4. Install your application. You can install your application using either the administrative console or the scripting tool. During installation, WebSphere Application Server inspects all resource references and requires you to supply a JNDI name for each of them. This is not an arbitrary JNDI name, but the JNDI name given to a particular, configured resource that is the target of the reference.

5. Manage existing mail providers and sessions. You can update and remove mail providers and sessions.

   To update mail providers and sessions:

   1. Open the administrative console.

   2. Click Resources > Mail in the console navigation tree.

   3. Select the appropriate Java Mail resource to modify by clicking either Mail Providers or Mail Sessions.

   4. Select the specific resource to modify. To remove a mail provider or mail session, select the check box next to the appropriate resource and click Delete.

   5. Click Apply or OK.

   6. Save the configuration.

6. Enable debugger for a mail session.

What to do next

Related tasks