Folder (Java EE 5 SDK)

javax.mail Class Folder

java.lang.Object
  javax.mail.Folder

public abstract class Folder

extends Object

Folder is an abstract class that represents a folder for mail messages. Subclasses implement protocol specific Folders.

Folders can contain Messages, other Folders or both, thus providing a tree-like hierarchy rooted at the Store's default folder. (Note that some Folder implementations may not allow both Messages and other Folders in the same Folder).

The interpretation of folder names is implementation dependent. The different levels of hierarchy in a folder's full name are separated from each other by the hierarchy delimiter character.

The case-insensitive full folder name (that is, the full name relative to the default folder for a Store) INBOX is reserved to mean the "primary folder for this user on this server". Not all Stores will provide an INBOX folder, and not all users will have an INBOX folder at all times. The name INBOX is reserved to refer to this folder, when it exists, in Stores that provide it.

A Folder object obtained from a Store need not actually exist in the backend store. The exists method tests whether the folder exists or not. The create method creates a Folder.

A Folder is initially in the closed state. Certain methods are valid in this state; the documentation for those methods note this. A Folder is opened by calling its 'open' method. All Folder methods, except open, delete and renameTo, are valid in this state.

The only way to get a Folder is by invoking the getFolder method on Store, Folder, or Session, or by invoking the list or listSubscribed methods on Folder. Folder objects returned by the above methods are not cached by the Store. Thus, invoking the getFolder method with the same folder name multiple times will return distinct Folder objects. Likewise for the list and listSubscribed methods.

The Message objects within the Folder are cached by the Folder. Thus, invoking getMessage(msgno) on the same message number multiple times will return the same Message object, until an expunge is done on this Folder.

Note that a Message's message number can change within a session if the containing Folder is expunged using the expunge method. Clients that use message numbers as references to messages should be aware of this and should be prepared to deal with situation (probably by flushing out existing message number references and reloading them). Because of this complexity, it is better for clients to use Message objects as references to messages, rather than message numbers. Expunged Message objects still have to be pruned, but other Message objects in that folder are not affected by the expunge.

作者:

John Mani, Bill Shannon

store

protected Store store

The parent store.

mode

protected int mode

The open mode of this folder. The open mode is Folder.READ_ONLY, Folder.READ_WRITE, or -1 if not known.

从以下版本开始:

JavaMail 1.1

HOLDS_MESSAGES

public static final int HOLDS_MESSAGES

This folder can contain messages

另请参见:

常量字段

HOLDS_FOLDERS

public static final int HOLDS_FOLDERS

This folder can contain other folders

另请参见:

常量字段

READ_ONLY

public static final int READ_ONLY

The Folder is read only. The state and contents of this folder cannot be modified.

另请参见:

常量字段

READ_WRITE

public static final int READ_WRITE

The state and contents of this folder can be modified.

另请参见:

常量字段

Folder

protected Folder(Store store)

Constructor that takes a Store object.

参数:

store - the Store that holds this folder

getName

public abstract String getName()

Returns the name of this Folder.

This method can be invoked on a closed Folder.

返回:

name of the Folder

getFullName

public abstract String getFullName()

Returns the full name of this Folder. If the folder resides under the root hierarchy of this Store, the returned name is relative to the root. Otherwise an absolute name, starting with the hierarchy delimiter, is returned.

This method can be invoked on a closed Folder.

返回:

full name of the Folder

getURLName

public URLName getURLName()
                   throws MessagingException

Return a URLName representing this folder. The returned URLName does not include the password used to access the store.

返回:

the URLName representing this folder

抛出异常:

MessagingException

从以下版本开始:

JavaMail 1.1

另请参见:

URLName

getStore

public Store getStore()

Returns the Store that owns this Folder object. This method can be invoked on a closed Folder.

返回:

the Store

getParent

public abstract Folder getParent()
                          throws MessagingException

Returns the parent folder of this folder. This method can be invoked on a closed Folder. If this folder is the top of a folder hierarchy, this method returns null.

Note that since Folder objects are not cached, invoking this method returns a new distinct Folder object.

返回:

Parent folder

抛出异常:

MessagingException

exists

public abstract boolean exists()
                        throws MessagingException

Tests if this folder physically exists on the Store. This method can be invoked on a closed Folder.

返回:

true if the folder exists, otherwise false

抛出异常:

MessagingException - typically if the connection to the server is lost.

另请参见:

create(int)

list

public abstract Folder[] list(String pattern)
                       throws MessagingException

Returns a list of Folders belonging to this Folder's namespace that match the specified pattern. Patterns may contain the wildcard characters "%", which matches any character except hierarchy delimiters, and "*", which matches any character.

As an example, given the folder hierarchy:

    Personal/
       Finance/
          Stocks
          Bonus
          StockOptions
       Jokes
 

list("*") on "Personal" will return the whole hierarchy.
list("%") on "Personal" will return "Finance" and "Jokes".
list("Jokes") on "Personal" will return "Jokes".
list("Stock*") on "Finance" will return "Stocks" and "StockOptions".

Folder objects are not cached by the Store, so invoking this method on the same pattern multiple times will return that many distinct Folder objects.

This method can be invoked on a closed Folder.

参数:

pattern - the match pattern

返回:

array of matching Folder objects. An empty array is returned if no matching Folders exist.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

另请参见:

listSubscribed(java.lang.String)

listSubscribed

public Folder[] listSubscribed(String pattern)
                        throws MessagingException

Returns a list of subscribed Folders belonging to this Folder's namespace that match the specified pattern. If the folder does not support subscription, this method should resolve to list. (The default implementation provided here, does just this). The pattern can contain wildcards as for list.

Note that, at a given level of the folder hierarchy, a particular folder may not be subscribed, but folders underneath that folder in the folder hierarchy may be subscribed. In order to allow walking the folder hierarchy, such unsubscribed folders may be returned, indicating that a folder lower in the hierarchy is subscribed. The isSubscribed method on a folder will tell whether any particular folder is actually subscribed.

Folder objects are not cached by the Store, so invoking this method on the same pattern multiple times will return that many distinct Folder objects.

This method can be invoked on a closed Folder.

参数:

pattern - the match pattern

返回:

array of matching subscribed Folder objects. An empty array is returned if no matching subscribed folders exist.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

另请参见:

list(java.lang.String)

list

public Folder[] list()
              throws MessagingException

Convenience method that returns the list of folders under this Folder. This method just calls the list(String pattern) method with "%" as the match pattern. This method can be invoked on a closed Folder.

返回:

array of Folder objects under this Folder. An empty array is returned if no subfolders exist.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

另请参见:

list(java.lang.String)

listSubscribed

public Folder[] listSubscribed()
                        throws MessagingException

Convenience method that returns the list of subscribed folders under this Folder. This method just calls the listSubscribed(String pattern) method with "%" as the match pattern. This method can be invoked on a closed Folder.

返回:

array of subscribed Folder objects under this Folder. An empty array is returned if no subscribed subfolders exist.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

另请参见:

listSubscribed(java.lang.String)

getSeparator

public abstract char getSeparator()
                           throws MessagingException

Return the delimiter character that separates this Folder's pathname from the names of immediate subfolders. This method can be invoked on a closed Folder.

返回:

Hierarchy separator character

抛出异常:

FolderNotFoundException - if the implementation requires the folder to exist, but it does not

MessagingException

getType

public abstract int getType()
                     throws MessagingException

Returns the type of this Folder, that is, whether this folder can hold messages or subfolders or both. The returned value is an integer bitfield with the appropriate bits set. This method can be invoked on a closed folder.

返回:

integer with appropriate bits set

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

另请参见:

HOLDS_FOLDERS, HOLDS_MESSAGES

create

public abstract boolean create(int type)
                        throws MessagingException

Create this folder on the Store. When this folder is created, any folders in its path that do not exist are also created.

If the creation is successful, a CREATED FolderEvent is delivered to any FolderListeners registered on this Folder and this Store.

参数:

type - The type of this folder.

返回:

true if the creation succeeds, else false.

抛出异常:

MessagingException

另请参见:

HOLDS_FOLDERS, HOLDS_MESSAGES, FolderEvent

isSubscribed

public boolean isSubscribed()

Returns true if this Folder is subscribed.

This method can be invoked on a closed Folder.

The default implementation provided here just returns true.

返回:

true if this Folder is subscribed

setSubscribed

public void setSubscribed(boolean subscribe)
                   throws MessagingException

Subscribe or unsubscribe this Folder. Not all Stores support subscription.

This method can be invoked on a closed Folder.

The implementation provided here just throws the MethodNotSupportedException.

参数:

subscribe - true to subscribe, false to unsubscribe

抛出异常:

FolderNotFoundException - if this folder does not exist.

MethodNotSupportedException - if this store does not support subscription

MessagingException

hasNewMessages

public abstract boolean hasNewMessages()
                                throws MessagingException

Returns true if this Folder has new messages since the last time this indication was reset. When this indication is set or reset depends on the Folder implementation (and in the case of IMAP, depends on the server). This method can be used to implement a lightweight "check for new mail" operation on a Folder without opening it. (For example, a thread that monitors a mailbox and flags when it has new mail.) This method should indicate whether any messages in the Folder have the RECENT flag set.

Note that this is not an incremental check for new mail, i.e., it cannot be used to determine whether any new messages have arrived since the last time this method was invoked. To implement incremental checks, the Folder needs to be opened.

This method can be invoked on a closed Folder that can contain Messages.

返回:

true if the Store has new Messages

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

getFolder

public abstract Folder getFolder(String name)
                          throws MessagingException

Return the Folder object corresponding to the given name. Note that this folder does not physically have to exist in the Store. The exists() method on a Folder indicates whether it really exists on the Store.

In some Stores, name can be an absolute path if it starts with the hierarchy delimiter. Otherwise, it is interpreted relative to this Folder.

Folder objects are not cached by the Store, so invoking this method on the same name multiple times will return that many distinct Folder objects.

This method can be invoked on a closed Folder.

参数:

name - name of the Folder

返回:

Folder object

抛出异常:

MessagingException

delete

public abstract boolean delete(boolean recurse)
                        throws MessagingException

Delete this Folder. This method will succeed only on a closed Folder.

The recurse flag controls whether the deletion affects subfolders or not. If true, all subfolders are deleted, then this folder itself is deleted. If false, the behaviour is dependent on the folder type and is elaborated below:

• The folder can contain only messages: (type == HOLDS_MESSAGES).
  All messages within the folder are removed. The folder itself is then removed. An appropriate FolderEvent is generated by the Store and this folder.

• The folder can contain only subfolders: (type == HOLDS_FOLDERS).
  If this folder is empty (does not contain any subfolders at all), it is removed. An appropriate FolderEvent is generated by the Store and this folder.
  If this folder contains any subfolders, the delete fails and returns false.

• The folder can contain subfolders as well as messages:
  If the folder is empty (no messages or subfolders), it is removed. If the folder contains no subfolders, but only messages, then all messages are removed. The folder itself is then removed. In both the above cases, an appropriate FolderEvent is generated by the Store and this folder.

  If the folder contains subfolders there are 3 possible choices an implementation is free to do:

  1. The operation fails, irrespective of whether this folder contains messages or not. Some implementations might elect to go with this simple approach. The delete() method returns false.
  2. Any messages within the folder are removed. Subfolders are not removed. The folder itself is not removed or affected in any manner. The delete() method returns true. And the exists() method on this folder will return true indicating that this folder still exists.
     An appropriate FolderEvent is generated by the Store and this folder.
  3. Any messages within the folder are removed. Subfolders are not removed. The folder itself changes its type from HOLDS_FOLDERS | HOLDS_MESSAGES to HOLDS_FOLDERS. Thus new messages cannot be added to this folder, but new subfolders can be created underneath. The delete() method returns true indicating success. The exists() method on this folder will return true indicating that this folder still exists.
     An appropriate FolderEvent is generated by the Store and this folder.

返回:

true if the Folder is deleted successfully

抛出异常:

FolderNotFoundException - if this folder does not exist

IllegalStateException - if this folder is not in the closed state.

MessagingException

另请参见:

FolderEvent

renameTo

public abstract boolean renameTo(Folder f)
                          throws MessagingException

Rename this Folder. This method will succeed only on a closed Folder.

If the rename is successful, a RENAMED FolderEvent is delivered to FolderListeners registered on this folder and its containing Store.

参数:

f - a folder representing the new name for this Folder

返回:

true if the Folder is renamed successfully

抛出异常:

FolderNotFoundException - if this folder does not exist

IllegalStateException - if this folder is not in the closed state.

MessagingException

另请参见:

FolderEvent

open

public abstract void open(int mode)
                   throws MessagingException

Open this Folder. This method is valid only on Folders that can contain Messages and that are closed.

If this folder is opened successfully, an OPENED ConnectionEvent is delivered to any ConnectionListeners registered on this Folder.

The effect of opening multiple connections to the same folder on a specifc Store is implementation dependent. Some implementations allow multiple readers, but only one writer. Others allow multiple writers as well as readers.

参数:

mode - open the Folder READ_ONLY or READ_WRITE

抛出异常:

FolderNotFoundException - if this folder does not exist.

IllegalStateException - if this folder is not in the closed state.

MessagingException

另请参见:

READ_ONLY, READ_WRITE, getType(), ConnectionEvent

close

public abstract void close(boolean expunge)
                    throws MessagingException

Close this Folder. This method is valid only on open Folders.

A CLOSED ConnectionEvent is delivered to any ConnectionListeners registered on this Folder. Note that the folder is closed even if this method terminates abnormally by throwing a MessagingException.

参数:

expunge - expunges all deleted messages if this flag is true

抛出异常:

IllegalStateException - if this folder is not opened

MessagingException

另请参见:

ConnectionEvent

isOpen

public abstract boolean isOpen()

Indicates whether this Folder is in the 'open' state.

返回:

true if this Folder is in the 'open' state.

getMode

public int getMode()

Return the open mode of this folder. Returns Folder.READ_ONLY, Folder.READ_WRITE, or -1 if the open mode is not known (usually only because an older Folder provider has not been updated to use this new method).

返回:

the open mode of this folder

抛出异常:

IllegalStateException - if this folder is not opened

从以下版本开始:

JavaMail 1.1

getPermanentFlags

public abstract Flags getPermanentFlags()

Get the permanent flags supported by this Folder. Returns a Flags object that contains all the flags supported.

The special flag Flags.USER indicates that this Folder supports arbitrary user-defined flags.

The supported permanent flags for a folder may not be available until the folder is opened.

返回:

permanent flags, or null if not known

getMessageCount

public abstract int getMessageCount()
                             throws MessagingException

Get total number of messages in this Folder.

This method can be invoked on a closed folder. However, note that for some folder implementations, getting the total message count can be an expensive operation involving actually opening the folder. In such cases, a provider can choose not to support this functionality in the closed state, in which case this method must return -1.

Clients invoking this method on a closed folder must be aware that this is a potentially expensive operation. Clients must also be prepared to handle a return value of -1 in this case.

返回:

total number of messages. -1 may be returned by certain implementations if this method is invoked on a closed folder.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

getNewMessageCount

public int getNewMessageCount()
                       throws MessagingException

Get the number of new messages in this Folder.

This method can be invoked on a closed folder. However, note that for some folder implementations, getting the new message count can be an expensive operation involving actually opening the folder. In such cases, a provider can choose not to support this functionality in the closed state, in which case this method must return -1.

Clients invoking this method on a closed folder must be aware that this is a potentially expensive operation. Clients must also be prepared to handle a return value of -1 in this case.

This implementation returns -1 if this folder is closed. Else this implementation gets each Message in the folder using getMessage(int) and checks whether its RECENT flag is set. The total number of messages that have this flag set is returned.

返回:

number of new messages. -1 may be returned by certain implementations if this method is invoked on a closed folder.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

getUnreadMessageCount

public int getUnreadMessageCount()
                          throws MessagingException

Get the total number of unread messages in this Folder.

This method can be invoked on a closed folder. However, note that for some folder implementations, getting the unread message count can be an expensive operation involving actually opening the folder. In such cases, a provider can choose not to support this functionality in the closed state, in which case this method must return -1.

Clients invoking this method on a closed folder must be aware that this is a potentially expensive operation. Clients must also be prepared to handle a return value of -1 in this case.

This implementation returns -1 if this folder is closed. Else this implementation gets each Message in the folder using getMessage(int) and checks whether its SEEN flag is set. The total number of messages that do not have this flag set is returned.

返回:

total number of unread messages. -1 may be returned by certain implementations if this method is invoked on a closed folder.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

getDeletedMessageCount

public int getDeletedMessageCount()
                           throws MessagingException

Get the number of deleted messages in this Folder.

This method can be invoked on a closed folder. However, note that for some folder implementations, getting the deleted message count can be an expensive operation involving actually opening the folder. In such cases, a provider can choose not to support this functionality in the closed state, in which case this method must return -1.

Clients invoking this method on a closed folder must be aware that this is a potentially expensive operation. Clients must also be prepared to handle a return value of -1 in this case.

This implementation returns -1 if this folder is closed. Else this implementation gets each Message in the folder using getMessage(int) and checks whether its DELETED flag is set. The total number of messages that have this flag set is returned.

返回:

number of deleted messages. -1 may be returned by certain implementations if this method is invoked on a closed folder.

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException

从以下版本开始:

JavaMail 1.3

getMessage

public abstract Message getMessage(int msgnum)
                            throws MessagingException

Get the Message object corresponding to the given message number. A Message object's message number is the relative position of this Message in its Folder. Messages are numbered starting at 1 through the total number of message in the folder. Note that the message number for a particular Message can change during a session if other messages in the Folder are deleted and the Folder is expunged.

Message objects are light-weight references to the actual message that get filled up on demand. Hence Folder implementations are expected to provide light-weight Message objects.

Unlike Folder objects, repeated calls to getMessage with the same message number will return the same Message object, as long as no messages in this folder have been expunged.

Since message numbers can change within a session if the folder is expunged , clients are advised not to use message numbers as references to messages. Use Message objects instead.

参数:

msgnum - the message number

返回:

the Message object

抛出异常:

FolderNotFoundException - if this folder does not exist.

IllegalStateException - if this folder is not opened

IndexOutOfBoundsException - if the message number is out of range.

MessagingException

另请参见:

getMessageCount(), fetch(javax.mail.Message[], javax.mail.FetchProfile)

getMessages

public Message[] getMessages(int start,
                             int end)
                      throws MessagingException

Get the Message objects for message numbers ranging from start through end, both start and end inclusive. Note that message numbers start at 1, not 0.

Message objects are light-weight references to the actual message that get filled up on demand. Hence Folder implementations are expected to provide light-weight Message objects.

This implementation uses getMessage(index) to obtain the required Message objects. Note that the returned array must contain (end-start+1) Message objects.

参数:

start - the number of the first message

end - the number of the last message

返回:

the Message objects

抛出异常:

FolderNotFoundException - if this folder does not exist.

IllegalStateException - if this folder is not opened.

IndexOutOfBoundsException - if the start or end message numbers are out of range.

MessagingException

另请参见:

fetch(javax.mail.Message[], javax.mail.FetchProfile)

getMessages

public Message[] getMessages(int[] msgnums)
                      throws MessagingException

Get the Message objects for message numbers specified in the array.

Message objects are light-weight references to the actual message that get filled up on demand. Hence Folder implementations are expected to provide light-weight Message objects.

This implementation uses getMessage(index) to obtain the required Message objects. Note that the returned array must contain msgnums.length Message objects

参数:

msgnums - the array of message numbers

返回:

the array of Message objects.

抛出异常:

FolderNotFoundException - if this folder does not exist.

IllegalStateException - if this folder is not opened.

IndexOutOfBoundsException - if any message number in the given array is out of range.

MessagingException

另请参见:

fetch(javax.mail.Message[], javax.mail.FetchProfile)

getMessages

public Message[] getMessages()
                      throws MessagingException

Get all Message objects from this Folder. Returns an empty array if the folder is empty. Clients can use Message objects (instead of sequence numbers) as references to the messages within a folder; this method supplies the Message objects to the client. Folder implementations are expected to provide light-weight Message objects, which get filled on demand.

This implementation invokes getMessageCount() to get the current message count and then uses getMessage() to get Message objects from 1 till the message count.

返回:

array of Message objects, empty array if folder is empty.

抛出异常:

FolderNotFoundException - if this folder does not exist.

IllegalStateException - if this folder is not opened.

MessagingException

另请参见:

fetch(javax.mail.Message[], javax.mail.FetchProfile)

appendMessages

public abstract void appendMessages(Message[] msgs)
                             throws MessagingException

Append given Messages to this folder. This method can be invoked on a closed Folder. An appropriate MessageCountEvent is delivered to any MessageCountListener registered on this folder when the messages arrive in the folder.

Folder implementations must not abort this operation if a Message in the given message array turns out to be an expunged Message.

参数:

msgs - array of Messages to be appended

抛出异常:

FolderNotFoundException - if this folder does not exist.

MessagingException - if the append failed.

fetch

public void fetch(Message[] msgs,
                  FetchProfile fp)
           throws MessagingException

Prefetch the items specified in the FetchProfile for the given Messages.

Clients use this method to indicate that the specified items are needed en-masse for the given message range. Implementations are expected to retrieve these items for the given message range in a efficient manner. Note that this method is just a hint to the implementation to prefetch the desired items.

An example is a client filling its header-view window with the Subject, From and X-mailer headers for all messages in the folder.

  Message[] msgs = folder.getMessages();

  FetchProfile fp = new FetchProfile();
  fp.add(FetchProfile.Item.ENVELOPE);
  fp.add("X-mailer");
  folder.fetch(msgs, fp);
  
  for (int i = 0; i < folder.getMessageCount(); i++) {
      display(msg[i].getFrom());
      display(msg[i].getSubject());
      display(msg[i].getHeader("X-mailer"));
  }

 

The implementation provided here just returns without doing anything useful. Providers wanting to provide a real implementation for this method should override this method.

参数:

msgs - fetch items for these messages

fp - the FetchProfile

抛出异常:

IllegalStateException - if this folder is not opened

MessagingException.

MessagingException

setFlags

public void setFlags(Message[] msgs,
                     Flags flag,
                     boolean value)
              throws MessagingException

Set the specified flags on the messages specified in the array. This will result in appropriate MessageChangedEvents being delivered to any MessageChangedListener registered on this Message's containing folder.

Note that the specified Message objects must belong to this folder. Certain Folder implementations can optimize the operation of setting Flags for a group of messages, so clients might want to use this method, rather than invoking Message.setFlags for each Message.

This implementation degenerates to invoking setFlags() on each Message object. Specific Folder implementations that can optimize this case should do so. Also, an implementation must not abort the operation if a Message in the array turns out to be an expunged Message.

参数:

msgs - the array of message objects

flag - Flags object containing the flags to be set

value - set the flags to this boolean value

抛出异常:

IllegalStateException - if this folder is not opened or if it has been opened READ_ONLY.

MessagingException

另请参见:

Message.setFlags(javax.mail.Flags, boolean), MessageChangedEvent

setFlags

public void setFlags(int start,
                     int end,
                     Flags flag,
                     boolean value)
              throws MessagingException

Set the specified flags on the messages numbered from start through end, both start and end inclusive. Note that message numbers start at 1, not 0. This will result in appropriate MessageChangedEvents being delivered to any MessageChangedListener registered on this Message's containing folder.

Certain Folder implementations can optimize the operation of setting Flags for a group of messages, so clients might want to use this method, rather than invoking Message.setFlags for each Message.

The default implementation uses getMessage(int) to get each Message object and then invokes setFlags on that object to set the flags. Specific Folder implementations that can optimize this case should do so. Also, an implementation must not abort the operation if a message number refers to an expunged message.

参数:

start - the number of the first message

end - the number of the last message

flag - Flags object containing the flags to be set

value - set the flags to this boolean value

抛出异常:

IllegalStateException - if this folder is not opened or if it has been opened READ_ONLY.

IndexOutOfBoundsException - if the start or end message numbers are out of range.

MessagingException

另请参见:

Message.setFlags(javax.mail.Flags, boolean), MessageChangedEvent

setFlags

public void setFlags(int[] msgnums,
                     Flags flag,
                     boolean value)
              throws MessagingException

Set the specified flags on the messages whose message numbers are in the array. This will result in appropriate MessageChangedEvents being delivered to any MessageChangedListener registered on this Message's containing folder.

Certain Folder implementations can optimize the operation of setting Flags for a group of messages, so clients might want to use this method, rather than invoking Message.setFlags for each Message.

The default implementation uses getMessage(int) to get each Message object and then invokes setFlags on that object to set the flags. Specific Folder implementations that can optimize this case should do so. Also, an implementation must not abort the operation if a message number refers to an expunged message.

参数:

msgnums - the array of message numbers

flag - Flags object containing the flags to be set

value - set the flags to this boolean value

抛出异常:

IllegalStateException - if this folder is not opened or if it has been opened READ_ONLY.

IndexOutOfBoundsException - if any message number in the given array is out of range.

MessagingException

另请参见:

Message.setFlags(javax.mail.Flags, boolean), MessageChangedEvent

copyMessages

public void copyMessages(Message[] msgs,
                         Folder folder)
                  throws MessagingException

Copy the specified Messages from this Folder into another Folder. This operation appends these Messages to the destination Folder. The destination Folder does not have to be opened. An appropriate MessageCountEvent is delivered to any MessageCountListener registered on the destination folder when the messages arrive in the folder.

Note that the specified Message objects must belong to this folder. Folder implementations might be able to optimize this method by doing server-side copies.

This implementation just invokes appendMessages() on the destination folder to append the given Messages. Specific folder implementations that support server-side copies should do so, if the destination folder's Store is the same as this folder's Store. Also, an implementation must not abort the operation if a Message in the array turns out to be an expunged Message.

参数:

msgs - the array of message objects

folder - the folder to copy the messages to

抛出异常:

FolderNotFoundException - if the destination folder does not exist.

IllegalStateException - if this folder is not opened.

MessagingException

另请参见:

appendMessages(javax.mail.Message[])

expunge

public abstract Message[] expunge()
                           throws MessagingException

Expunge (permanently remove) messages marked DELETED. Returns an array containing the expunged message objects. The getMessageNumber method on each of these message objects returns that Message's original (that is, prior to the expunge) sequence number. A MessageCountEvent containing the expunged messages is delivered to any MessageCountListeners registered on the folder.

Expunge causes the renumbering of Message objects subsequent to the expunged messages. Clients that use message numbers as references to messages should be aware of this and should be prepared to deal with the situation (probably by flushing out existing message number caches and reloading them). Because of this complexity, it is better for clients to use Message objects as references to messages, rather than message numbers. Any expunged Messages objects still have to be pruned, but other Messages in that folder are not affected by the expunge.

After a message is expunged, only the isExpunged and getMessageNumber methods are still valid on the corresponding Message object; other methods may throw MessageRemovedException

返回:

array of expunged Message objects

抛出异常:

FolderNotFoundException - if this folder does not exist

IllegalStateException - if this folder is not opened.

MessagingException

另请参见:

Message.isExpunged(), MessageCountEvent

search

public Message[] search(SearchTerm term)
                 throws MessagingException

Search this Folder for messages matching the specified search criterion. Returns an array containing the matching messages . Returns an empty array if no matches were found.

This implementation invokes search(term, getMessages()), to apply the search over all the messages in this folder. Providers that can implement server-side searching might want to override this method to provide a more efficient implementation.

参数:

term - the search criterion

返回:

array of matching messages

抛出异常:

SearchException - if the search term is too complex for the implementation to handle.

FolderNotFoundException - if this folder does not exist.

IllegalStateException - if this folder is not opened.

MessagingException

另请参见:

SearchTerm

search

public Message[] search(SearchTerm term,
                        Message[] msgs)
                 throws MessagingException

Search the given array of messages for those that match the specified search criterion. Returns an array containing the matching messages. Returns an empty array if no matches were found.

Note that the specified Message objects must belong to this folder.

This implementation iterates through the given array of messages, and applies the search criterion on each message by calling its match() method with the given term. The messages that succeed in the match are returned. Providers that can implement server-side searching might want to override this method to provide a more efficient implementation. If the search term is too complex or contains user-defined terms that cannot be executed on the server, providers may elect to either throw a SearchException or degenerate to client-side searching by calling super.search() to invoke this implementation.

参数:

term - the search criterion

msgs - the messages to be searched

返回:

array of matching messages

抛出异常:

SearchException - if the search term is too complex for the implementation to handle.

IllegalStateException - if this folder is not opened

MessagingException

另请参见:

SearchTerm

addConnectionListener

public void addConnectionListener(ConnectionListener l)

Add a listener for Connection events on this Folder.

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

参数:

l - the Listener for Connection events

另请参见:

ConnectionEvent

removeConnectionListener

public void removeConnectionListener(ConnectionListener l)

Remove a Connection event listener.

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

参数:

l - the listener

另请参见:

addConnectionListener(javax.mail.event.ConnectionListener)

notifyConnectionListeners

protected void notifyConnectionListeners(int type)

Notify all ConnectionListeners. Folder implementations are expected to use this method to broadcast connection events.

The provided implementation queues the event into an internal event queue. An event dispatcher thread dequeues events from the queue and dispatches them to the registered ConnectionListeners. Note that the event dispatching occurs in a separate thread, thus avoiding potential deadlock problems.

参数:

type - the ConnectionEvent type

另请参见:

ConnectionEvent

addFolderListener

public void addFolderListener(FolderListener l)

Add a listener for Folder events on this Folder.

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

参数:

l - the Listener for Folder events

另请参见:

FolderEvent

removeFolderListener

public void removeFolderListener(FolderListener l)

Remove a Folder event listener.

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

参数:

l - the listener

另请参见:

addFolderListener(javax.mail.event.FolderListener)

notifyFolderListeners

protected void notifyFolderListeners(int type)

Notify all FolderListeners registered on this Folder and this folder's Store. Folder implementations are expected to use this method to broadcast Folder events.

The implementation provided here queues the event into an internal event queue. An event dispatcher thread dequeues events from the queue and dispatches them to the FolderListeners registered on this folder. The implementation also invokes notifyFolderListeners on this folder's Store to notify any FolderListeners registered on the store.

参数:

type - type of FolderEvent

另请参见:

notifyFolderRenamedListeners(javax.mail.Folder)

notifyFolderRenamedListeners

protected void notifyFolderRenamedListeners(Folder folder)

Notify all FolderListeners registered on this Folder and this folder's Store about the renaming of this folder. Folder implementations are expected to use this method to broadcast Folder events indicating the renaming of folders.

The implementation provided here queues the event into an internal event queue. An event dispatcher thread dequeues events from the queue and dispatches them to the FolderListeners registered on this folder. The implementation also invokes notifyFolderRenamedListeners on this folder's Store to notify any FolderListeners registered on the store.

参数:

folder - Folder representing the new name.

从以下版本开始:

JavaMail 1.1

另请参见:

notifyFolderListeners(int)

addMessageCountListener

public void addMessageCountListener(MessageCountListener l)

Add a listener for MessageCount events on this Folder.

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

参数:

l - the Listener for MessageCount events

另请参见:

MessageCountEvent

removeMessageCountListener

public void removeMessageCountListener(MessageCountListener l)

Remove a MessageCount listener.

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

参数:

l - the listener

另请参见:

addMessageCountListener(javax.mail.event.MessageCountListener)

notifyMessageAddedListeners

protected void notifyMessageAddedListeners(Message[] msgs)

Notify all MessageCountListeners about the addition of messages into this folder. Folder implementations are expected to use this method to broadcast MessageCount events for indicating arrival of new messages.

The provided implementation queues the event into an internal event queue. An event dispatcher thread dequeues events from the queue and dispatches them to the registered MessageCountListeners. Note that the event dispatching occurs in a separate thread, thus avoiding potential deadlock problems.

notifyMessageRemovedListeners

protected void notifyMessageRemovedListeners(boolean removed,
                                             Message[] msgs)

Notify all MessageCountListeners about the removal of messages from this Folder. Folder implementations are expected to use this method to broadcast MessageCount events indicating removal of messages.

The provided implementation queues the event into an internal event queue. An event dispatcher thread dequeues events from the queue and dispatches them to the registered MessageCountListeners. Note that the event dispatching occurs in a separate thread, thus avoiding potential deadlock problems.

addMessageChangedListener

public void addMessageChangedListener(MessageChangedListener l)

Add a listener for MessageChanged events on this Folder.

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

参数:

l - the Listener for MessageChanged events

另请参见:

MessageChangedEvent

removeMessageChangedListener

public void removeMessageChangedListener(MessageChangedListener l)

Remove a MessageChanged listener.

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

参数:

l - the listener

另请参见:

addMessageChangedListener(javax.mail.event.MessageChangedListener)

notifyMessageChangedListeners

protected void notifyMessageChangedListeners(int type,
                                             Message msg)

Notify all MessageChangedListeners. Folder implementations are expected to use this method to broadcast MessageChanged events.

The provided implementation queues the event into an internal event queue. An event dispatcher thread dequeues events from the queue and dispatches them to registered MessageChangedListeners. Note that the event dispatching occurs in a separate thread, thus avoiding potential deadlock problems.

finalize

protected void finalize()
                 throws Throwable

重写:

finalize in class Object

抛出异常:

Throwable

toString

public String toString()

override the default toString(), it will return the String from Folder.getFullName() or if that is null, it will use the default toString() behavior.

重写:

toString in class Object

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