public interface UIDFolder
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 for more information. All the Folder objects returned by the default IMAP provider implement the UIDFolder interface. Use it as follows:
Folder f = store.getFolder("whatever");
UIDFolder uf = (UIDFolder)f;
long uid = uf.getUID(msg);
| Modifier and Type | Interface and Description |
|---|---|
static class |
UIDFolder.FetchProfileItem
A fetch profile item for fetching UIDs.
|
| Modifier and Type | Field and Description |
|---|---|
static 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. |
static long |
MAXUID
The largest value possible for a UID, a 32-bit unsigned integer.
|
| Modifier and Type | Method and Description |
|---|---|
Message |
getMessageByUID(long uid)
Get the Message corresponding to the given UID.
|
Message[] |
getMessagesByUID(long[] uids)
Get the Messages specified by the given array of UIDs.
|
Message[] |
getMessagesByUID(long start,
long end)
Get the Messages specified by the given range.
|
long |
getUID(Message message)
Get the UID for the specified message.
|
long |
getUIDNext()
Returns the predicted UID that will be assigned to the
next message that is appended to this folder.
|
long |
getUIDValidity()
Returns the UIDValidity value associated with this folder.
|
static final long LASTUID
end
parameter in getMessagesByUID(start, end), to denote the
UID of the last message in the folder.static final long MAXUID
Folder f = store.getFolder("whatever");
UIDFolder uf = (UIDFolder)f;
Message[] newMsgs =
uf.getMessagesByUID(lastSeenUID + 1, UIDFolder.MAXUID);
long getUIDValidity()
throws MessagingException
Clients typically compare this value against a UIDValidity value saved from a previous session to insure that any cached UIDs are not stale.
MessagingException - for failuresMessage getMessageByUID(long uid) throws MessagingException
null is returned.uid - UID for the desired messagenull is returned
if no message corresponding to this UID is obtained.MessagingException - for failuresMessage[] getMessagesByUID(long start, long end) throws MessagingException
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.
start - start UIDend - end UIDMessagingException - for failuresLASTUIDMessage[] getMessagesByUID(long[] uids) throws MessagingException
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.
uids - array of UIDsMessagingException - for failureslong getUID(Message message) throws MessagingException
message - Message from this folderjava.util.NoSuchElementException - if the given Message
is not in this Folder.MessagingException - for other failureslong getUIDNext()
throws MessagingException
If the value is unknown, -1 is returned.
MessagingException - for failures