oracle.cabo.servlet.state
Class QueueStateManager

java.lang.Object
  |
  +--oracle.cabo.servlet.state.QueueStateManager

All Implemented Interfaces:

java.io.Serializable, StateManager

public class QueueStateManager

extends java.lang.Object

implements StateManager

A StateManager that stores states in a FIFO queue of a predetermined length. State IDs are created randomly, and encoded into 8-char hexadecimal strings.

See Also:

Serialized Form

Constructor Summary

QueueStateManager()
Creates a QueueStateManager of a default size (20 states).

QueueStateManager(int queueSize)
Creates a QueueStateManager.

Method Summary

protected java.util.Random	createRandom() Creates the Random object that will be used to generate IDs.
void	expire() Invalidate this StateManager object, and all of its children State objects.
MutableState	getNewState() Creates a new, mutable State object.
protected java.lang.String	getNextID(java.util.Random random) Given a random number generator, generates a string.
State	getState(java.lang.String id) Returns a State based on ID.
boolean	isExpired() Tests whether the StateManager has been expired.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

QueueStateManager

public QueueStateManager()

Creates a QueueStateManager of a default size (20 states).

QueueStateManager

public QueueStateManager(int queueSize)

Creates a QueueStateManager.

Method Detail

expire

public void expire()

Description copied from interface: StateManager

Invalidate this StateManager object, and all of its children State objects. Once a StateManager has been invalidated, it can no longer be used to retrieve States.

Specified by:

expire in interface StateManager

isExpired

public boolean isExpired()

Description copied from interface: StateManager

Tests whether the StateManager has been expired.

Specified by:

isExpired in interface StateManager

getState

public State getState(java.lang.String id)

Description copied from interface: StateManager

Returns a State based on ID.

Specified by:

getState in interface StateManager

getNewState

public MutableState getNewState()

Description copied from interface: StateManager

Creates a new, mutable State object.

Specified by:

getNewState in interface StateManager

createRandom

protected java.util.Random createRandom()

Creates the Random object that will be used to generate IDs. The default implementation simply returns java.util.Random; a subclasser might chose to use SecureRandom for greater security. (=-=AEW Should SecureRandom be the default?)

getNextID

protected java.lang.String getNextID(java.util.Random random)

Given a random number generator, generates a string.