com.bea.netuix.application.notifications
Interface INotificationUserEnumerator

All Superinterfaces

Serializable

All Known Implementing Classes:

AggregatingNotificationUserEnumerator, CollectionNotificationUserEnumerator, CommunityMembershipsEnumerator, GroupNotificationUserEnumerator

public interface INotificationUserEnumerator
extends Serializable

Objects implementing this interface may be used to enumerate the set of users a notification should be sent to. This allows notifications to be sent to large sets of users without necessarily having all of the usernames ever stored in memory.

Implementations of this interface must be serializable, as the enumeration may well be executed in a different JVM than it was created in. For this reason, any necessary non-serializable resources must be obtained in the open() method and may be released in the close() method. The framework guarantees that open() will be called before any calls to the reset, hasNext or getNext methods are made, and that close() will be called after the enumeration is no longer needed.

The enumeration needs to be re-openable-- that is, after a call to close(), a call to open() should render the enumeration valid again.

This interface is meant to be used to represent a dynamic, possibly changing set of users. The iteration over this set may proceed in any order and may even change order after a call to the reset() method. The total return set (the unordered set of all usernames returned from the getNext() method) may even change after calls to the reset() method or if the enumeration has been closed and re-opened. The only requirement is that the enumeration must not return the same username twice unless a call to reset() has been made or the enumeration has been closed and re-opened.

Method Summary

void	close() Releases any resources used by this enumeration.
String	getNext() Returns the next username in the enumeration.
boolean	hasNext() Used to determine if more usernames are available from this enumeration.
void	open() Serves to initialize the enumeration.
void	reset() Used to reset the enumeration to the beginning.

Method Detail

open

void open()
          throws NotificationUserEnumerationException

Serves to initialize the enumeration. Any resources the enumeration needs may be obtained in this initialization method. This method is called before any calls to the reset, hasNext or getNext methods are made.

Throws

NotificationUserEnumerationException - if any problems were encountered.

reset

void reset()
           throws NotificationUserEnumerationException

Used to reset the enumeration to the beginning. This may be necessary if a transaction got rolled back and the NotificationManager is attempting to send the notification again.

It is not necessary that the enumeration proceed in the same order as it did previously, nor that the enumeration results in the same total return set-- in other words, the enumeration can be based entirely on dynamic criteria or data which may change over time. The only requirement is that an enumeration must not return the same username twice unless a call to reset() has been made.

Throws

NotificationUserEnumerationException - if any problems were encountered.

hasNext

boolean hasNext()
                throws NotificationUserEnumerationException

Used to determine if more usernames are available from this enumeration.

Returns

true as long as more usernames are available from the enumeration.

Throws

NotificationUserEnumerationException - if any problems were encountered.

getNext

String getNext()
               throws NotificationUserEnumerationException

Returns the next username in the enumeration.

Returns

the next username in the enumeration.

Throws

NotificationUserEnumerationException - if any problems were encountered.

close

void close()
           throws NotificationUserEnumerationException

Releases any resources used by this enumeration.

Throws

NotificationUserEnumerationException - if any problems were encountered.