org.springframework.webflow.execution
Interface FlowSession

All Known Implementing Classes:

MockFlowSession

public interface FlowSession

A single, local instantiation of a flow definition launched within an overall flow execution.

This object maintains all instance state including session status within exactly one governing FlowExecution, as well as the current flow state. This object also acts as the local "flow scope" data model. Data in flow scope lives for the life of this object and is cleaned up automatically when this object is destroyed. Destruction happens when this session enters an end state.

A flow session will go through several status changes during its lifecycle. Initially it will be FlowSessionStatus.CREATED when a new execution is started.

After passing through the FlowSessionStatus.STARTING status, the flow session is activated (about to be manipulated) and its status becomes FlowSessionStatus.ACTIVE. In the case of a new execution session activation happens immediately after creation to put the "root flow" at the top of the stack and transition it to its start state.

When control returns to the client for user think time the status is updated to FlowSessionStatus.PAUSED. The flow is no longer actively processing then, as it is stored off to a repository waiting on the user to resume.

If a flow session is pushed down in the stack because a subflow is spawned, its status becomes FlowSessionStatus.SUSPENDED until the subflow returns (ends) and is popped off the stack. The resuming flow session then becomes active once again.

When a flow session is terminated because an EndState is reached its status becomes FlowSessionStatus.ENDED, which ends its life. When this happens the session is popped off the stack and discarded, and any allocated resources in "flow scope" are automatically cleaned up.

Note that a flow session is in no way linked to an HTTP session. It just uses the familiar "session" naming convention to denote a stateful object.

Author:

Keith Donald, Erwin Vervaet

See Also:

FlowDefinition, FlowExecution, FlowSessionStatus

Method Summary

FlowDefinition	getDefinition() Returns the flow definition backing this session.
MutableAttributeMap	getFlashMap() Returns the local "flash map".
FlowSession	getParent() Returns the parent flow session in the current flow execution, or null if there is no parent flow session.
MutableAttributeMap	getScope() Return this session's local attributes; the basis for "flow scope" (flow session scope).
StateDefinition	getState() Returns the current state of this flow session.
FlowSessionStatus	getStatus() Returns the current status of this flow session.
boolean	isRoot() Returns whether this flow session is the root flow session in the ongoing flow execution.

Method Detail

getDefinition

FlowDefinition getDefinition()

Returns the flow definition backing this session.

getState

StateDefinition getState()

Returns the current state of this flow session. This value changes as the flow executes.

getStatus

FlowSessionStatus getStatus()

Returns the current status of this flow session. This value changes as the flow executes.

getScope

MutableAttributeMap getScope()

Return this session's local attributes; the basis for "flow scope" (flow session scope).

Returns:

the flow scope attributes

getFlashMap

MutableAttributeMap getFlashMap()

Returns the local "flash map". Attributes in this map are cleared out on the next event signaled in the flow execution, so they survive a refresh.

Returns:

the flash map

getParent

FlowSession getParent()

Returns the parent flow session in the current flow execution, or null if there is no parent flow session.

isRoot

boolean isRoot()

Returns whether this flow session is the root flow session in the ongoing flow execution. The root flow session does not have a parent flow session.