public interface

UIDFolder

com.google.code.javax.mail.UIDFolder
Known Indirect Subclasses

Class Overview

The UIDFolder interface is implemented by Folders that can support the "disconnected" mode of operation, by providing unique-ids for messages in the folder. This interface is based on the IMAP model for supporting disconnected operation.

A Unique identifier (UID) is a positive long value, assigned to each message in a specific folder. Unique identifiers are assigned in a strictly ascending fashion in the mailbox. That is, as each message is added to the mailbox it is assigned a higher UID than the message(s) which were added previously. Unique identifiers persist across sessions. This permits a client to resynchronize its state from a previous session with the server.

Associated with every mailbox is a unique identifier validity value. If unique identifiers from an earlier session fail to persist to this session, the unique identifier validity value must be greater than the one used in the earlier session.

Refer to RFC 2060 http://www.ietf.org/rfc/rfc2060.txt for more information.

Summary

Nested Classes
class UIDFolder.FetchProfileItem A fetch profile item for fetching UIDs. 
Constants
long LASTUID This is a special value that can be used as the end parameter in getMessagesByUID(start, end), to denote the UID of the last message in the folder.
Public Methods
abstract Message getMessageByUID(long uid)
Get the Message corresponding to the given UID.
abstract Message[] getMessagesByUID(long[] uids)
Get the Messages specified by the given array of UIDs.
abstract Message[] getMessagesByUID(long start, long end)
Get the Messages specified by the given range.
abstract long getUID(Message message)
Get the UID for the specified message.
abstract long getUIDValidity()
Returns the UIDValidity value associated with this folder.

Constants

public static final long LASTUID

This is a special value that can be used as the end parameter in getMessagesByUID(start, end), to denote the UID of the last message in the folder.

See Also
Constant Value: -1 (0xffffffffffffffff)

Public Methods

public abstract Message getMessageByUID (long uid)

Get the Message corresponding to the given UID. If no such message exists, null is returned.

Parameters
uid UID for the desired message
Returns
  • the Message object. null is returned if no message corresponding to this UID is obtained.
Throws
MessagingException

public abstract Message[] getMessagesByUID (long[] uids)

Get the Messages specified by the given array of UIDs. If any UID is invalid, null is returned for that entry.

Note that the returned array will be of the same size as the specified array of UIDs, and null entries may be present in the array to indicate invalid UIDs.

Parameters
uids Array of UIDs
Returns
  • array of Message objects
Throws
MessagingException

public abstract Message[] getMessagesByUID (long start, long end)

Get the Messages specified by the given range. The special value LASTUID can be used for the end parameter to indicate the UID of the last message in the folder.

Note that end need not be greater than start; the order of the range doesn't matter. Note also that, unless the folder is empty, use of LASTUID ensures that at least one message will be returned - the last message in the folder.

Parameters
start Start UID
end End UID
Returns
  • array of Message objects
Throws
MessagingException
See Also

public abstract long getUID (Message message)

Get the UID for the specified message. Note that the message must belong to this folder. Otherwise java.util.NoSuchElementException is thrown.

Parameters
message Message from this folder
Returns
  • UID for this message
Throws
NoSuchElementException if the given Message is not in this GmailFolder.
MessagingException

public abstract long getUIDValidity ()

Returns the UIDValidity value associated with this folder.

Clients typically compare this value against a UIDValidity value saved from a previous session to insure that any cached UIDs are not stale.

Returns
  • UIDValidity
Throws
MessagingException