org.springframework.webflow.engine
Class SubflowState

java.lang.Object
  org.springframework.webflow.engine.AnnotatedObject
      org.springframework.webflow.engine.State
          org.springframework.webflow.engine.TransitionableState
              org.springframework.webflow.engine.SubflowState

All Implemented Interfaces:

Annotated, StateDefinition, TransitionableStateDefinition

public class SubflowState
extends TransitionableState

A transitionable state that spawns a subflow when executed. When the subflow this state spawns ends, the ending result is used as grounds for a state transition out of this state.

A subflow state may be configured to map input data from its flow -- acting as the parent flow -- down to the subflow when the subflow is spawned. In addition, output data produced by the subflow may be mapped up to the parent flow when the subflow ends and the parent flow resumes. See the FlowAttributeMapper interface definition for more information on how to do this. The logic for ending a subflow is located in the EndState implementation.

Author:

Keith Donald, Erwin Vervaet

See Also:

FlowAttributeMapper, EndState

Field Summary

Fields inherited from class org.springframework.webflow.engine.State

logger

Fields inherited from class org.springframework.webflow.engine.AnnotatedObject

CAPTION_PROPERTY, DESCRIPTION_PROPERTY

Constructor Summary

SubflowState(Flow flow, java.lang.String id, Flow subflow)
Create a new subflow state.

Method Summary

protected void	appendToString(org.springframework.core.style.ToStringCreator creator) Subclasses may override this hook method to stringify their internal state.
protected MutableAttributeMap	createSubflowInput(RequestContext context) Create the input data map for the spawned subflow session.
protected ViewSelection	doEnter(RequestControlContext context) Specialization of State's doEnter template method that executes behaviour specific to this state type in polymorphic fashion.
FlowAttributeMapper	getAttributeMapper() Returns the attribute mapper used to map data between the parent and child flow, or null if no mapping is needed.
Flow	getSubflow() Returns the subflow spawned by this state.
ViewSelection	onEvent(RequestControlContext context) Called on completion of the subflow to handle the subflow result event as determined by the end state reached by the subflow.
void	setAttributeMapper(FlowAttributeMapper attributeMapper) Set the attribute mapper used to map model data between the parent and child flow.

Methods inherited from class org.springframework.webflow.engine.TransitionableState

exit, getExitActionList, getRequiredTransition, getTransitions, getTransitionSet, reenter

Methods inherited from class org.springframework.webflow.engine.State

enter, equals, getEntryActionList, getExceptionHandlerSet, getFlow, getId, getOwner, handleException, hashCode, isStartState, toString

Methods inherited from class org.springframework.webflow.engine.AnnotatedObject

getAttributeMap, getAttributes, getCaption, getDescription, setCaption, setDescription

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.springframework.webflow.definition.StateDefinition

getId, getOwner

Methods inherited from interface org.springframework.webflow.definition.Annotated

getAttributes, getCaption, getDescription

Constructor Detail

SubflowState

public SubflowState(Flow flow,
                    java.lang.String id,
                    Flow subflow)
             throws java.lang.IllegalArgumentException

Create a new subflow state.

Parameters:

flow - the owning flow

id - the state identifier (must be unique to the flow)

subflow - the subflow to spawn

Throws:

java.lang.IllegalArgumentException - when this state cannot be added to given flow, e.g. because the id is not unique

See Also:

setAttributeMapper(FlowAttributeMapper)

Method Detail

getSubflow

public Flow getSubflow()

Returns the subflow spawned by this state.

getAttributeMapper

public FlowAttributeMapper getAttributeMapper()

Returns the attribute mapper used to map data between the parent and child flow, or null if no mapping is needed.

setAttributeMapper

public void setAttributeMapper(FlowAttributeMapper attributeMapper)

Set the attribute mapper used to map model data between the parent and child flow. Can be null if no mapping is needed.

doEnter

protected ViewSelection doEnter(RequestControlContext context)
                         throws FlowExecutionException

Specialization of State's doEnter template method that executes behaviour specific to this state type in polymorphic fashion.

Entering this state, creates the subflow input map and spawns the subflow in the current flow execution.

Specified by:

doEnter in class State

Parameters:

context - the control context for the currently executing flow, used by this state to manipulate the flow execution

Returns:

a view selection containing model and view information needed to render the results of the state execution

Throws:

FlowExecutionException - if an exception occurs in this state

createSubflowInput

protected MutableAttributeMap createSubflowInput(RequestContext context)

Create the input data map for the spawned subflow session. The returned map will be passed to Flow.start(RequestControlContext, MutableAttributeMap).

onEvent

public ViewSelection onEvent(RequestControlContext context)

Called on completion of the subflow to handle the subflow result event as determined by the end state reached by the subflow.

Overrides:

onEvent in class TransitionableState

Parameters:

context - the flow execution control context

Returns:

the selected view

appendToString

protected void appendToString(org.springframework.core.style.ToStringCreator creator)

Description copied from class: State

Subclasses may override this hook method to stringify their internal state. This default implementation does nothing.

Overrides:

appendToString in class TransitionableState

Parameters:

creator - the toString creator, to stringify properties