ee.telekom.workflow.graph

Interface Node

All Known Implementing Classes:

AbstractConditionalGateway, AbstractGateway, AbstractNode, AndFork, AndJoin, BeanAsyncCallActivity, BeanCallActivity, CancellingDiscriminator, CatchSignal, CatchTimer, CreateNewInstanceActivity, HumanTaskActivity, ObjectCallActivity, OrFork, ScriptActivity, SetAttributeActivity, ThrowEscalation, ValidateAttributeActivity, XorFork, XorJoin

public interface Node

A Node corresponds to an action in a workflow definition. E.g. it may perform some function. In some cases it may not complete immediately, but enter a wait state. At some point it will be completed and the execution can continue.

Every node may have multiple outgoing Transitions. When a node is completed, it may pick which transition(s) to proceed trough.

Note, that node implementations may not contain any GraphInstance specific execution state. If a node implementation requires such state, this state either must reside in the Token implementation or in the graph instance's Environment.

Method Summary

Modifier and Type	Method and Description
void	cancel(GraphEngine engine, Token token) Called when the GraphEngine cancels the execution of a Token, that is currently pointing to this node and is in a wait state.
void	execute(GraphEngine engine, Token token) Performs node specific logic.
int	getId() Returns the node's unique id.
String	getName() Returns the node's name.
void	store(Environment environment, Object result) When a token execution on a node completes and returns control back to the engine, then the engine mandates the node to store the node execution result into the graph instance's environment.

Method Detail

getId

int getId()

Returns the node's unique id. The id must be unique to the containing Graph.

Returns:

the node's unique id

getName

String getName()

Returns the node's name. A node may have a name describing it within the workflow.

Returns:

the node's name

execute

void execute(GraphEngine engine,
             Token token)

Performs node specific logic. Either from the execute method, or later from the outside, the GraphEngineFacade#complete(WorkItem) method must be called to continue executing the GraphInstance.

Parameters:

engine - the GraphEngine which is performing the execution

token - the Token which is currently executing in this node

cancel

void cancel(GraphEngine engine,
            Token token)

Called when the GraphEngine cancels the execution of a Token, that is currently pointing to this node and is in a wait state.

Parameters:

engine - the GraphEngine which is performing the execution

token - the Token pointing to this node

store

void store(Environment environment,
           Object result)

When a token execution on a node completes and returns control back to the engine, then the engine mandates the node to store the node execution result into the graph instance's environment.

Parameters:

environment - the environment to store the result in

result - the result to be stored