Overview (Jakarta Mail API documentation)

Jakarta Mail API Packages
Package	Description
javax.mail	The Jakarta Mail API provides classes that model a mail system.
javax.mail.event	Listeners and events for the Jakarta Mail API.
javax.mail.internet	Classes specific to Internet mail systems.
javax.mail.search	Message search terms for the Jakarta Mail API.
javax.mail.util	Jakarta Mail API utility classes.

RI-specific Packages
Package	Description
com.sun.mail.dsn	Support for creating and parsing Delivery Status Notifications.
com.sun.mail.gimap	An EXPERIMENTAL IMAP protocol provider that supports the Gmail-specific IMAP protocol extensions .
com.sun.mail.imap	An IMAP protocol provider for the Jakarta Mail API that provides access to an IMAP message store.
com.sun.mail.pop3	A POP3 protocol provider for the Jakarta Mail API that provides access to a POP3 message store.
com.sun.mail.smtp	An SMTP protocol provider for the Jakarta Mail API that provides access to an SMTP server.
com.sun.mail.util	Utility classes for use with the Jakarta Mail API.
com.sun.mail.util.logging	Contains Jakarta Mail extensions for the Java™ platform's core logging facilities.

The Jakarta Mail 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 Jakarta Mail API includes the javax.mail package and subpackages.

For an overview of the Jakarta Mail API, read the Jakarta Mail 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("Jakarta Mail 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 Jakarta Mail download bundle contains many more complete examples in the "demo" directory.

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

Properties

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

The Jakarta Mail 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 Jakarta Mail 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 Jakarta Mail 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