Java tutorial
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If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package javax.mail; import java.io.*; import java.net.*; import java.util.*; import javax.mail.event.*; /** * An abstract class that models a message store and its * access protocol, for storing and retrieving messages. * Subclasses provide actual implementations. <p> * * Note that <code>Store</code> extends the <code>Service</code> * class, which provides many common methods for naming stores, * connecting to stores, and listening to connection events. * * @author John Mani * @author Bill Shannon * * @see javax.mail.Service * @see javax.mail.event.ConnectionEvent * @see javax.mail.event.StoreEvent */ public abstract class Store extends Service { /** * Constructor. * * @param session Session object for this Store. * @param urlname URLName object to be used for this Store */ protected Store(Session session, URLName urlname) { super(session, urlname); } /** * Returns a Folder object that represents the 'root' of * the default namespace presented to the user by the Store. * * @return the root Folder * @exception IllegalStateException if this Store is not connected. * @exception MessagingException for other failures */ public abstract Folder getDefaultFolder() throws MessagingException; /** * Return the Folder object corresponding to the given name. Note * that a Folder object is returned even if the named folder does * not physically exist on the Store. The <code>exists()</code> * method on the folder object indicates whether this folder really * exists. <p> * * 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. * * @param name The name of the Folder. In some Stores, name can * be an absolute path if it starts with the * hierarchy delimiter. Else it is interpreted * relative to the 'root' of this namespace. * @return Folder object * @exception IllegalStateException if this Store is not connected. * @exception MessagingException for other failures * @see Folder#exists * @see Folder#create */ public abstract Folder getFolder(String name) throws MessagingException; /** * Return a closed Folder object, corresponding to the given * URLName. The store specified in the given URLName should * refer to this Store object. <p> * * Implementations of this method may obtain the name of the * actual folder using the <code>getFile()</code> method on * URLName, and use that name to create the folder. * * @param url URLName that denotes a folder * @return Folder object * @exception IllegalStateException if this Store is not connected. * @exception MessagingException for other failures * @see URLName */ public abstract Folder getFolder(URLName url) throws MessagingException; /** * Return a set of folders representing the <i>personal</i> namespaces * for the current user. A personal namespace is a set of names that * is considered within the personal scope of the authenticated user. * Typically, only the authenticated user has access to mail folders * in their personal namespace. If an INBOX exists for a user, it * must appear within the user's personal namespace. In the * typical case, there should be only one personal namespace for each * user in each Store. <p> * * This implementation returns an array with a single entry containing * the return value of the <code>getDefaultFolder</code> method. * Subclasses should override this method to return appropriate information. * * @return array of Folder objects * @exception IllegalStateException if this Store is not connected. * @exception MessagingException for other failures * @since JavaMail 1.2 */ public Folder[] getPersonalNamespaces() throws MessagingException { return new Folder[] { getDefaultFolder() }; } /** * Return a set of folders representing the namespaces for * <code>user</code>. The namespaces returned represent the * personal namespaces for the user. To access mail folders in the * other user's namespace, the currently authenticated user must be * explicitly granted access rights. For example, it is common for * a manager to grant to their secretary access rights to their * mail folders. <p> * * This implementation returns an empty array. Subclasses should * override this method to return appropriate information. * * @param user the user name * @return array of Folder objects * @exception IllegalStateException if this Store is not connected. * @exception MessagingException for other failures * @since JavaMail 1.2 */ public Folder[] getUserNamespaces(String user) throws MessagingException { return new Folder[0]; } /** * Return a set of folders representing the <i>shared</i> namespaces. * A shared namespace is a namespace that consists of mail folders * that are intended to be shared amongst users and do not exist * within a user's personal namespace. <p> * * This implementation returns an empty array. Subclasses should * override this method to return appropriate information. * * @exception IllegalStateException if this Store is not connected. * @exception MessagingException for other failures * @return array of Folder objects * @since JavaMail 1.2 */ public Folder[] getSharedNamespaces() throws MessagingException { return new Folder[0]; } // Vector of Store listeners private volatile Vector<StoreListener> storeListeners = null; /** * Add a listener for StoreEvents on this Store. <p> * * The default implementation provided here adds this listener * to an internal list of StoreListeners. * * @param l the Listener for Store events * @see javax.mail.event.StoreEvent */ public synchronized void addStoreListener(StoreListener l) { if (storeListeners == null) storeListeners = new Vector<>(); storeListeners.addElement(l); } /** * Remove a listener for Store events. <p> * * The default implementation provided here removes this listener * from the internal list of StoreListeners. * * @param l the listener * @see #addStoreListener */ public synchronized void removeStoreListener(StoreListener l) { if (storeListeners != null) storeListeners.removeElement(l); } /** * Notify all StoreListeners. Store implementations are * expected to use this method to broadcast StoreEvents. <p> * * The provided default implementation queues the event into * an internal event queue. An event dispatcher thread dequeues * events from the queue and dispatches them to the registered * StoreListeners. Note that the event dispatching occurs * in a separate thread, thus avoiding potential deadlock problems. * * @param type the StoreEvent type * @param message a message for the StoreEvent */ protected void notifyStoreListeners(int type, String message) { if (storeListeners == null) return; StoreEvent e = new StoreEvent(this, type, message); queueEvent(e, storeListeners); } // Vector of folder listeners private volatile Vector<FolderListener> folderListeners = null; /** * Add a listener for Folder events on any Folder object * obtained from this Store. FolderEvents are delivered to * FolderListeners on the affected Folder as well as to * FolderListeners on the containing Store. <p> * * The default implementation provided here adds this listener * to an internal list of FolderListeners. * * @param l the Listener for Folder events * @see javax.mail.event.FolderEvent */ public synchronized void addFolderListener(FolderListener l) { if (folderListeners == null) folderListeners = new Vector<>(); folderListeners.addElement(l); } /** * Remove a listener for Folder events. <p> * * The default implementation provided here removes this listener * from the internal list of FolderListeners. * * @param l the listener * @see #addFolderListener */ public synchronized void removeFolderListener(FolderListener l) { if (folderListeners != null) folderListeners.removeElement(l); } /** * Notify all FolderListeners. Store implementations are * expected to use this method to broadcast Folder events. <p> * * The provided default implementation queues the event into * an internal event queue. An event dispatcher thread dequeues * events from the queue and dispatches them to the registered * FolderListeners. Note that the event dispatching occurs * in a separate thread, thus avoiding potential deadlock problems. * * @param type type of FolderEvent * @param folder affected Folder * @see #notifyFolderRenamedListeners */ protected void notifyFolderListeners(int type, Folder folder) { if (folderListeners == null) return; FolderEvent e = new FolderEvent(this, folder, type); queueEvent(e, folderListeners); } /** * Notify all FolderListeners about the renaming of a folder. * Store implementations are expected to use this method to broadcast * Folder events indicating the renaming of folders. <p> * * The provided default implementation queues the event into * an internal event queue. An event dispatcher thread dequeues * events from the queue and dispatches them to the registered * FolderListeners. Note that the event dispatching occurs * in a separate thread, thus avoiding potential deadlock problems. * * @param oldF the folder being renamed * @param newF the folder representing the new name. * @since JavaMail 1.1 */ protected void notifyFolderRenamedListeners(Folder oldF, Folder newF) { if (folderListeners == null) return; FolderEvent e = new FolderEvent(this, oldF, newF, FolderEvent.RENAMED); queueEvent(e, folderListeners); } }