A Session can provide server-side storage of state/data between HTML pages. After creating a new session (which can be manipulated using at: and at:put:), it can be saved on the Sessions list by asking the Session class to store: the session. A random integer is returned as a key to the session, and the key can be stored in an HTML page in a hidden field.

A session can be retrieved by ID by asking Session to recall: an ID. A session can be retired when it is no longer useful.

Each recall: or use at:/at:put: "touches" (updates) the Session's last use time. A Session that is older than a certain period (default 30 minutes, in viableTime instance method) will generate an error. Every hour, the PWS, as part of its backup procedures, will clear out old sessions.

	initialize
	initialize

	store/recall
	clearOld recall: retire: store:

	access	top
	at: Primitive. Assumes receiver is indexable. Answer the value of an indexable element in the receiver. Fail if the argument index is not an Integer or is out of bounds. Essential. See Object documentation whatIsAPrimitive.
	at:put: Primitive. Assumes receiver is indexable. Store the argument value in the indexable element of the receiver indicated by index. Fail if the index is not an Integer or is out of bounds. Or fail if the value is not of the right type for this kind of collection. Answer the value that was stored. Essential. See Object documentation whatIsAPrimitive.
	isViable
	touch
	viableTime In seconds

	initialize	top
	initialize

	initialization	top
	initialize Object initialize
	new Answer a new instance of the receiver (which is a class) with no indexable variables. Fail if the class is indexable.

	store/recall	top
	clearOld
	recall:
	retire:
	store: