org.springframework.webflow.engine

Interface RequestControlContext

All Superinterfaces:

RequestContext

All Known Implementing Classes:

MockRequestControlContext

public interface RequestControlContext
extends RequestContext

Mutable control interface used to manipulate an ongoing flow execution in the context of one client request. Primarily used internally by the various flow artifacts when they are invoked.

This interface acts as a facade for core definition constructs such as the central Flow and State classes, abstracting away details about the runtime execution machine.

Note this type is not the same as the FlowExecutionContext. Objects of this type are request specific: they provide a control interface for manipulating exactly one flow execution locally from exactly one request. A FlowExecutionContext provides information about a single flow execution (conversation), and it's scope is not local to a specific request (or thread).

Author:

Keith Donald, Erwin Vervaet

See Also:

Flow, State, FlowExecution, FlowExecutionContext

Method Summary

Methods

Modifier and Type	Method and Description
FlowExecutionKey	assignFlowExecutionKey() Assign the ongoing flow execution its flow execution key.
void	endActiveFlowSession(java.lang.String outcome, MutableAttributeMap output) End the active flow session of the current flow execution.
boolean	execute(Transition transition) Execute this transition out of the current source state.
boolean	getEmbeddedMode() Returns true if the flow current flow execution was launched in embedded page mode.
boolean	getRedirectInSameState() Returns the value of the 'redirect in same state' flow execution attribute if set or otherwise it falls back on the value returned by getRedirectOnPause().
boolean	getRedirectOnPause() Returns true if the 'redirect on pause' flow execution attribute is set to true, false otherwise.
boolean	handleEvent(Event event) Signals the occurrence of an event in the current state of this flow execution request context.
void	removeAllFlowExecutionSnapshots() Remove all flow execution snapshots associated with the ongoing conversation.
void	removeCurrentFlowExecutionSnapshot() Remove the current flow execution snapshot to invalidate the current state.
void	setCurrentState(State state) Record the current state that has entered in the executing flow.
void	setCurrentTransition(Transition transition) Record the transition executing in the flow.
void	setCurrentView(View view) Sets the current view.
void	start(Flow flow, MutableAttributeMap input) Spawn a new flow session and activate it in the currently executing flow.
void	updateCurrentFlowExecutionSnapshot() Update the current flow execution snapshot to save the current state.
void	viewRendered(View view) Called when the current view has completed rendering in the current view state.
void	viewRendering(View view) Called when the current view is about to be rendered in the current view state.

Methods inherited from interface org.springframework.webflow.execution.RequestContext

getActiveFlow, getAttributes, getConversationScope, getCurrentEvent, getCurrentState, getCurrentTransition, getCurrentView, getExternalContext, getFlashScope, getFlowExecutionContext, getFlowExecutionUrl, getFlowScope, getMatchingTransition, getMessageContext, getRequestParameters, getRequestScope, getViewScope, inViewState

Method Detail

setCurrentState

void setCurrentState(State state)

Record the current state that has entered in the executing flow. This method will be called as part of entering a new state by the State type itself.

Parameters:

state - the current state

See Also:

State.enter(RequestControlContext)

assignFlowExecutionKey

FlowExecutionKey assignFlowExecutionKey()

Assign the ongoing flow execution its flow execution key. This method will be called before a state is about to render a view and pause the flow execution.

setCurrentView

void setCurrentView(View view)

Sets the current view.

Parameters:

view - the current view, or null to mark the current view as null

viewRendering

void viewRendering(View view)

Called when the current view is about to be rendered in the current view state.

Parameters:

view - the view to be rendered

viewRendered

void viewRendered(View view)

Called when the current view has completed rendering in the current view state.

Parameters:

view - the view that rendered

handleEvent

boolean handleEvent(Event event)
                    throws FlowExecutionException

Signals the occurrence of an event in the current state of this flow execution request context. This method should be called by clients that report internal event occurrences, such as action states. The onEvent() method of the flow involved in the flow execution will be called.

Parameters:

event - the event that occurred

Returns:

a boolean indicating if handling this event caused the current state to exit and a new state to enter

Throws:

FlowExecutionException - if an exception was thrown within a state of the flow during execution of this signalEvent operation

See Also:

Flow.handleEvent(RequestControlContext)

execute

boolean execute(Transition transition)

Execute this transition out of the current source state. Allows for privileged execution of an arbitrary transition.

Parameters:

transition - the transition

See Also:

Transition.execute(State, RequestControlContext)

setCurrentTransition

void setCurrentTransition(Transition transition)

Record the transition executing in the flow. This method will be called as part of executing a transition from one state to another.

Parameters:

transition - the transition being executed

See Also:

Transition.execute(State, RequestControlContext)

updateCurrentFlowExecutionSnapshot

void updateCurrentFlowExecutionSnapshot()

Update the current flow execution snapshot to save the current state.

removeCurrentFlowExecutionSnapshot

void removeCurrentFlowExecutionSnapshot()

Remove the current flow execution snapshot to invalidate the current state.

removeAllFlowExecutionSnapshots

void removeAllFlowExecutionSnapshots()

Remove all flow execution snapshots associated with the ongoing conversation. Invalidates previous states.

start

void start(Flow flow,
         MutableAttributeMap input)
           throws FlowExecutionException

Spawn a new flow session and activate it in the currently executing flow. Also transitions the spawned flow to its start state. This method should be called by clients that wish to spawn new flows, such as subflow states.

This will start a new flow session in the current flow execution, which is already active.

Parameters:

flow - the flow to start, its start() method will be called

input - initial contents of the newly created flow session (may be null, e.g. empty)

Throws:

FlowExecutionException - if an exception was thrown within a state of the flow during execution of this start operation

See Also:

Flow.start(RequestControlContext, MutableAttributeMap)

endActiveFlowSession

void endActiveFlowSession(java.lang.String outcome,
                        MutableAttributeMap output)
                          throws java.lang.IllegalStateException

End the active flow session of the current flow execution. This method should be called by clients that terminate flows, such as end states. The end() method of the flow involved in the flow execution will be called.

Parameters:

outcome - the logical outcome the ending session should return

output - output the ending session should return

Throws:

java.lang.IllegalStateException - when the flow execution is not active

See Also:

Flow.end(RequestControlContext, String, MutableAttributeMap)

getRedirectOnPause

boolean getRedirectOnPause()

Returns true if the 'redirect on pause' flow execution attribute is set to true, false otherwise.

Returns:

true or false

getRedirectInSameState

boolean getRedirectInSameState()

Returns the value of the 'redirect in same state' flow execution attribute if set or otherwise it falls back on the value returned by getRedirectOnPause().

Returns:

true or false

getEmbeddedMode

boolean getEmbeddedMode()

Returns true if the flow current flow execution was launched in embedded page mode. When a flow is embedded on a page it can make different assumptions with regards to whether redirect after post is necessary.