Package javax.mail

The JavaMail™ API provides classes that model a mail system. The javax.mail package defines classes that are common to all mail systems. The javax.mail.internet package defines classes that are specific to mail systems based on internet standards such as MIME, SMTP, POP3, and IMAP. The JavaMail API includes the javax.mail package and subpackages.

For an overview of the JavaMail API, read the JavaMail specification.

The code to send a plain text message can be as simple as the following: 

    Properties props = new Properties();
    props.put("mail.smtp.host", "my-mail-server");
    Session session = Session.getInstance(props, null);

    try {
        MimeMessage msg = new MimeMessage(session);
        msg.setFrom("me@example.com");
        msg.setRecipients(Message.RecipientType.TO,
                          "you@example.com");
        msg.setSubject("JavaMail hello world example");
        msg.setSentDate(new Date());
        msg.setText("Hello, world!\n");
        Transport.send(msg, "me@example.com", "my-password");
    } catch (MessagingException mex) {
        System.out.println("send failed, exception: " + mex);
    }

The JavaMail download bundle contains many more complete examples in the "demo" directory.

Don't forget to see the JavaMail API FAQ for answers to the most common questions. The JavaMail web site contains many additional resources.

Properties

The JavaMail API supports the following standard properties, which may be set in the Session object, or in the Properties object used to create the Session object. The properties are always set as strings; the Type column describes how the string is interpreted. For example, use 

        props.put("mail.debug", "true");

to set the mail.debug property, which is of type boolean.

Name Type Description
mail.debug boolean The initial debug mode. Default is false.
mail.from String The return email address of the current user, used by the InternetAddress method getLocalAddress.
mail.mime.address.strict boolean The MimeMessage class uses the InternetAddress method parseHeader to parse headers in messages. This property controls the strict flag passed to the parseHeader method. The default is true.
mail.host String The default host name of the mail server for both Stores and Transports. Used if the mail.protocol.host property isn't set.
mail.store.protocol String Specifies the default message access protocol. The Session method getStore() returns a Store object that implements this protocol. By default the first Store provider in the configuration files is returned.
mail.transport.protocol String Specifies the default message transport protocol. The Session method getTransport() returns a Transport object that implements this protocol. By default the first Transport provider in the configuration files is returned.
mail.user String The default user name to use when connecting to the mail server. Used if the mail.protocol.user property isn't set.
mail.protocol.class String Specifies the fully qualified class name of the provider for the specified protocol. Used in cases where more than one provider for a given protocol exists; this property can be used to specify which provider to use by default. The provider must still be listed in a configuration file.
mail.protocol.host String The host name of the mail server for the specified protocol. Overrides the mail.host property.
mail.protocol.port int The port number of the mail server for the specified protocol. If not specified the protocol's default port number is used.
mail.protocol.user String The user name to use when connecting to mail servers using the specified protocol. Overrides the mail.user property.

The following properties are supported by the reference implementation (RI) of JavaMail, but are not currently a required part of the specification. The names, types, defaults, and semantics of these properties may change in future releases.

Name Type Description
mail.debug.auth boolean Include protocol authentication commands (including usernames and passwords) in the debug output. Default is false.
mail.debug.auth.username boolean Include the user name in non-protocol debug output. Default is true.
mail.debug.auth.password boolean Include the password in non-protocol debug output. Default is false.
mail.transport.protocol.address-type String Specifies the default message transport protocol for the specified address type. The Session method getTransport(Address) returns a Transport object that implements this protocol when the address is of the specified type (e.g., "rfc822" for standard internet addresses). By default the first Transport configured for that address type is used. This property can be used to override the behavior of the send method of the Transport class so that (for example) the "smtps" protocol is used instead of the "smtp" protocol by setting the property mail.transport.protocol.rfc822 to "smtps".
mail.event.scope String Controls the scope of events. (See the javax.mail.event package.) By default, a separate event queue and thread is used for events for each Store, Transport, or Folder. If this property is set to "session", all such events are put in a single event queue processed by a single thread for the current session. If this property is set to "application", all such events are put in a single event queue processed by a single thread for the current application. (Applications are distinguished by their context class loader.)
mail.event.executor java.util.concurrent.Executor By default, a new Thread is created for each event queue. This thread is used to call the listeners for these events. If this property is set to an instance of an Executor, the Executor.execute method is used to run the event dispatcher for an event queue. The event dispatcher runs until the event queue is no longer in use.

The JavaMail API also supports several System properties; see the javax.mail.internet package documentation for details.

The JavaMail reference implementation includes protocol providers in subpackages of com.sun.mail. Note that the APIs to these protocol providers are not part of the standard JavaMail API. Portable programs will not use these APIs.

Nonportable programs may use the APIs of the protocol providers by (for example) casting a returned Folder object to a com.sun.mail.imap.IMAPFolder object. Similarly for Store and Message objects returned from the standard JavaMail APIs.

The protocol providers also support properties that are specific to those providers. The package documentation for the IMAP, POP3, and SMTP packages provide details.

In addition to printing debugging output as controlled by the Session configuration, the current implementation of classes in this package log the same information using Logger as described in the following table:

Logger Name Logging Level Purpose
javax.mail CONFIG Configuration of the Session
javax.mail FINE General debugging output