javax.mail

Class Service

java.lang.Object

javax.mail.Service

All Implemented Interfaces:

java.lang.AutoCloseable

Direct Known Subclasses:

Store, Transport

public abstract class Service
extends java.lang.Object
implements java.lang.AutoCloseable

An abstract class that contains the functionality common to messaging services, such as stores and transports.

A messaging service is created from a Session and is named using a URLName. A service must be connected before it can be used. Connection events are sent to reflect its connection status.

Method Summary

Modifier and Type	Method and Description
void	addConnectionListener(ConnectionListener l) Add a listener for Connection events on this service.
void	close() Close this service and terminate its connection.
void	connect() A generic connect method that takes no parameters.
void	connect(java.lang.String host, int port, java.lang.String user, java.lang.String password) Similar to connect(host, user, password) except a specific port can be specified.
void	connect(java.lang.String user, java.lang.String password) Connect to the current host using the specified username and password.
void	connect(java.lang.String host, java.lang.String user, java.lang.String password) Connect to the specified address.
URLName	getURLName() Return a URLName representing this service.
boolean	isConnected() Is this service currently connected?
void	removeConnectionListener(ConnectionListener l) Remove a Connection event listener.
java.lang.String	toString() Return getURLName.toString() if this service has a URLName, otherwise it will return the default toString.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

connect

public void connect()
             throws MessagingException

A generic connect method that takes no parameters. Subclasses can implement the appropriate authentication schemes. Subclasses that need additional information might want to use some properties or might get it interactively using a popup window.

If the connection is successful, an "open" ConnectionEvent is delivered to any ConnectionListeners on this service.

Most clients should just call this method to connect to the service.

It is an error to connect to an already connected service.

The implementation provided here simply calls the following connect(String, String, String) method with nulls.

Throws:

AuthenticationFailedException - for authentication failures

MessagingException - for other failures

java.lang.IllegalStateException - if the service is already connected

See Also:

ConnectionEvent

connect

public void connect(java.lang.String host,
                    java.lang.String user,
                    java.lang.String password)
             throws MessagingException

Connect to the specified address. This method provides a simple authentication scheme that requires a username and password.

If the connection is successful, an "open" ConnectionEvent is delivered to any ConnectionListeners on this service.

It is an error to connect to an already connected service.

The implementation in the Service class will collect defaults for the host, user, and password from the session, from the URLName for this service, and from the supplied parameters and then call the protocolConnect method. If the protocolConnect method returns false, the user will be prompted for any missing information and the protocolConnect method will be called again. The subclass should override the protocolConnect method. The subclass should also implement the getURLName method, or use the implementation in this class.

On a successful connection, the setURLName method is called with a URLName that includes the information used to make the connection, including the password.

If the username passed in is null, a default value will be chosen as described above. If the password passed in is null and this is the first successful connection to this service, the user name and the password collected from the user will be saved as defaults for subsequent connection attempts to this same service when using other Service object instances (the connection information is typically always saved within a particular Service object instance). The password is saved using the Session method setPasswordAuthentication. If the password passed in is not null, it is not saved, on the assumption that the application is managing passwords explicitly.

Parameters:

host - the host to connect to

user - the user name

password - this user's password

Throws:

AuthenticationFailedException - for authentication failures

MessagingException - for other failures

java.lang.IllegalStateException - if the service is already connected

See Also:

ConnectionEvent, Session.setPasswordAuthentication(javax.mail.URLName, javax.mail.PasswordAuthentication)

connect

public void connect(java.lang.String user,
                    java.lang.String password)
             throws MessagingException

Connect to the current host using the specified username and password. This method is equivalent to calling the connect(host, user, password) method with null for the host name.

Parameters:

user - the user name

password - this user's password

Throws:

AuthenticationFailedException - for authentication failures

MessagingException - for other failures

java.lang.IllegalStateException - if the service is already connected

Since:

JavaMail 1.4

See Also:

ConnectionEvent, Session.setPasswordAuthentication(javax.mail.URLName, javax.mail.PasswordAuthentication), connect(java.lang.String, java.lang.String, java.lang.String)

connect

public void connect(java.lang.String host,
                    int port,
                    java.lang.String user,
                    java.lang.String password)
             throws MessagingException

Similar to connect(host, user, password) except a specific port can be specified.

Parameters:

host - the host to connect to

port - the port to connect to (-1 means the default port)

user - the user name

password - this user's password

Throws:

AuthenticationFailedException - for authentication failures

MessagingException - for other failures

java.lang.IllegalStateException - if the service is already connected

See Also:

connect(java.lang.String, java.lang.String, java.lang.String), ConnectionEvent

isConnected

public boolean isConnected()

Is this service currently connected?

This implementation uses a private boolean field to store the connection state. This method returns the value of that field.

Subclasses may want to override this method to verify that any connection to the message store is still alive.

Returns:

true if the service is connected, false if it is not connected

close

public void close()
           throws MessagingException

Close this service and terminate its connection. A close ConnectionEvent is delivered to any ConnectionListeners. Any Messaging components (Folders, Messages, etc.) belonging to this service are invalid after this service is closed. Note that the service is closed even if this method terminates abnormally by throwing a MessagingException.

This implementation uses setConnected(false) to set this service's connected state to false. It will then send a close ConnectionEvent to any registered ConnectionListeners. Subclasses overriding this method to do implementation specific cleanup should call this method as a last step to insure event notification, probably by including a call to super.close() in a finally clause.

Specified by:

close in interface java.lang.AutoCloseable

Throws:

MessagingException - for errors while closing

See Also:

ConnectionEvent

getURLName

public URLName getURLName()

Return a URLName representing this service. The returned URLName does not include the password field.

Subclasses should only override this method if their URLName does not follow the standard format.

The implementation in the Service class returns (usually a copy of) the url field with the password and file information stripped out.

Returns:

the URLName representing this service

See Also:

URLName

addConnectionListener

public void addConnectionListener(ConnectionListener l)

Add a listener for Connection events on this service.

The default implementation provided here adds this listener to an internal list of ConnectionListeners.

Parameters:

l - the Listener for Connection events

See Also:

ConnectionEvent

removeConnectionListener

public void removeConnectionListener(ConnectionListener l)

Remove a Connection event listener.

The default implementation provided here removes this listener from the internal list of ConnectionListeners.

Parameters:

l - the listener

See Also:

addConnectionListener(javax.mail.event.ConnectionListener)

toString

public java.lang.String toString()

Return getURLName.toString() if this service has a URLName, otherwise it will return the default toString.

Overrides:

toString in class java.lang.Object