| java.lang.Object
 sunlabs.brazil.session.SessionManager
All known Subclasses: sunlabs.brazil.session.SerialPersist, sunlabs.brazil.session.PJamaSessionManager, sunlabs.brazil.session.CacheManager,
| SessionManager | | public class SessionManager (Code) | | The SessionManager associates an object with a Session ID
to give Handlers the ability to maintain state that lasts for the
duration of a session instead of just for the duration of a request.
An example of session-lifetime information is the set of stocks that
a particular user is interested in. When the hypothetical
StockHandler gets a request, it would get determine which
stocks to display based on the Session ID of the request.
Operating with the SessionManager is the mechanism to
discover the Session ID of a request and/or create new Session IDs.
For example, the first time a user goes to the server providing the stock
market information, they could get a cookie. Subsequently, every time
they visit the stock market page the cookie present in the request
would be decoded and matched with the existing Session ID for use by
the StockHandler.
The SessionManager operates as a bag of globally
accessible resources. Existing subclasses of the
SessionManager also provide persistence, that is, a way to
recover these resources even if the server process is terminated and
later restarted, to get back to the state things were in.
author:
Stephen Uhler (stephen.uhler@sun.com)
author:
Colin Stevens (colin.stevens@sun.com)
version:
1.12, 00/12/08 |
| Field Summary | |
| protected Hashtable | sessions
A Hashtable used when mapping Session IDs to objects.
Keys are session objects. |
| Method Summary | |
| public static Object | getSession(Object session, Object ident, Class type)
Returns the object associated with the given Session ID. | | public Object | getSessionObject(Object session, Object ident, Class type)
Returns the object associated with the given Session ID and ident.
This is the instance method that is invoked by the static method
SessionManager.getSession. | | public static void | setSessionManager(SessionManager mgr)
Installs the given SessionManager object as the
default session manager to be invoked when getSession
is called. |
| sessions | | protected Hashtable sessions(Code) | | A Hashtable used when mapping Session IDs to objects.
Keys are session objects. Values are another
Hashtable (hashtable B).
Each key in hashtable B is the ident and each value is the
persistent object returned by getSession. Also,
hashtable B is the object that is returned by getSession
if the ident is null.
|
| getSession | | public static Object getSession(Object session, Object ident, Class type)(Code) | | Returns the object associated with the given Session ID. Passing in
the same (hash-key equivalent) Session ID will return the same object.
This static method will dispatch to the currently installed
SessionManager instance.
Parameters:
session - The Session ID for the persistent session information. Ifthe session does not exist, a new one is created.May be null to get informationnot associated with a particular Session ID, but that someHandler wants to make persistent anyhow.
Parameters:
ident - An arbitray identifier used to determine which object(associated with the given session) the callerwants. May be null to return theHashtable that contains all the objectsassociated with the given Session ID.
Parameters:
type - The Class of the object to create. If the givensession and ident did not specifyan existing object, a new one is created by callingnewInstance based on the type.If null, then this method returnsnull if the object didn't exist, instead ofallocating a new object. The return value depends upon session,ident and type as follows: | session | ident | type | result |
|---|
| exists | exists | -- | Returns existing object. type is ignored. | | exists | doesn't exist | class | Returns newInstance of class. | | exists | doesn't exist | null | Returns null. | | exists | null | -- | Returns Hashtable of all objects forgiven session. | | doesn't exist | specified | -- | Creates a new session | | doesn't exist | null | -- | Returns null. | null | -- | -- | As above, but information is about the "no-session". |
|
| getSessionObject | | public Object getSessionObject(Object session, Object ident, Class type)(Code) | | Returns the object associated with the given Session ID and ident.
This is the instance method that is invoked by the static method
SessionManager.getSession. Implementors of Session
Managers provide one of these. Users call
SessionManager.getSession .
|
| setSessionManager | | public static void setSessionManager(SessionManager mgr)(Code) | | Installs the given SessionManager object as the
default session manager to be invoked when getSession
is called.
Parameters:
mgr - The SessionManager object. |
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