ee.telekom.workflow.graph

Interface GraphEngineFacade

All Known Subinterfaces:

GraphEngine

All Known Implementing Classes:

GraphEngineImpl

public interface GraphEngineFacade

A GraphEngineFacade is the interface that external systems should use to communicated with a graph engine.

An graph engine executes a workflow. A Graph specifies how it should be executed and a GraphInstance tracks the current state of execution. It is an graph engine which creates instances of GraphInstance and Token. Engines must be thread-safe. Thus implementations of interface may be safely shared among threads.

Method Summary

Modifier and Type	Method and Description
void	abort(GraphInstance instance) Aborts the given GraphInstance's execution and cancels all associated tokens and work items.
void	complete(GraphWorkItem workItem) Completes the executed work item and continues execution until another wait state is reached or until the graph instance is completed.
BeanResolver	getBeanResolver() Returns the engine's BeanResolver, or null if the engine does not support to resolve beans.
NewGraphInstanceCreator	getNewGraphInstanceCreator() Returns the engine's NewGraphInstanceCreator, or null if the engine does not support to create sub graph instances.
GraphRepository	getRepository() Returns the engine's GraphRepository.
void	registerInstanceEventListener(GraphInstanceEventListener listener) Adds a GraphInstanceEventListener to the engine.
void	registerNodeEventListener(NodeEventListener listener) Adds a NodeEventListener to the engine.
void	registerWorkItemEventListener(GraphWorkItemEventListener listener) Adds a GraphWorkItemEventListener to the engine.
GraphInstance	start(Graph graph) A shorthand for #start(Graph, Environment, String) using an empty initial environment and a null external id.
GraphInstance	start(Graph graph, Environment initialEnvironment)
GraphInstanceImpl	start(Graph graph, Environment initialEnvironment, Long externalId) Starts a GraphInstance of the given Graph using the given Environment.
GraphInstance	start(String graphName) A shorthand for #start(String, Integer, Environment, String) using the latest graph with the given name and an empty initial environment and a null external id.
GraphInstance	start(String graphName, Integer version) A shorthand for #start(String, Integer, Environment, String) using an empty initial environment and a null external id.
GraphInstance	start(String graphName, Integer version, Environment initialEnvironment) A shorthand for #start(String, Integer, Environment, String) using a null external id.
GraphInstance	start(String graphName, Integer version, Environment initialEnvironment, Long externalId) Starts a GraphInstance of the Graph with the given name and version and using the given Environment and associates the created GraphInstance with the given external.

Method Detail

start

GraphInstance start(String graphName)

A shorthand for #start(String, Integer, Environment, String) using the latest graph with the given name and an empty initial environment and a null external id.

start

GraphInstance start(String graphName,
                    Integer version)

A shorthand for #start(String, Integer, Environment, String) using an empty initial environment and a null external id.

start

GraphInstance start(String graphName,
                    Integer version,
                    Environment initialEnvironment)

A shorthand for #start(String, Integer, Environment, String) using a null external id.

start

GraphInstance start(String graphName,
                    Integer version,
                    Environment initialEnvironment,
                    Long externalId)

Starts a GraphInstance of the Graph with the given name and version and using the given Environment and associates the created GraphInstance with the given external. Is the equivalent of doing

 Graph graph = engine.getRepository().getLatestGraph(graphName);
 GraphInstance graphInstance = engine.start(graph, initialEnvironment,
                externalId);
 

If no graph is found for the given graphName, a WorkflowException will be thrown.

Parameters:

graphName - the name of the graph to execute

version - the version of the graph to execute of null for the latest graph with the given name.

initialEnvironment - A starting environment for the GraphInstance. All attributes from this environment will be copied into the new graph instance's environment before execution starts.

externalId - the external id that the graph instance is associated with

Returns:

a GraphInstance of the latest Graph with the given name and using the given Environment which has already been started (and, given that no wait states were entered, is already completed).

Throws:

WorkflowException - If no graph is found with the given graphName

start

GraphInstance start(Graph graph)

A shorthand for #start(Graph, Environment, String) using an empty initial environment and a null external id.

start

GraphInstance start(Graph graph,
                    Environment initialEnvironment)

start

GraphInstanceImpl start(Graph graph,
                        Environment initialEnvironment,
                        Long externalId)

Starts a GraphInstance of the given Graph using the given Environment. A Token will be generated for the start node (determined by Graph.getStartNode()), and this token will be executed. If the graph does not contain nodes which go into a wait state, the GraphInstance returned will be completed.

Before the graph instance is started, the given initial environment will be copied into the one of the new graph instance.

Parameters:

graph - the graph to create a graph instance of

initialEnvironment - an initial environment for the graph instance

externalId - the external id that the graph instance is associated with

abort

void abort(GraphInstance instance)

Aborts the given GraphInstance's execution and cancels all associated tokens and work items.

Parameters:

instance - the graph instance to abort

complete

void complete(GraphWorkItem workItem)

Completes the executed work item and continues execution until another wait state is reached or until the graph instance is completed.

Parameters:

workItem - the work item to complete

getRepository

GraphRepository getRepository()

Returns the engine's GraphRepository.

Returns:

the engine's GraphRepository

getBeanResolver

BeanResolver getBeanResolver()

Returns the engine's BeanResolver, or null if the engine does not support to resolve beans.

Returns:

the engine's BeanResolver, or null if the engine does not support to resolve beans.

getNewGraphInstanceCreator

NewGraphInstanceCreator getNewGraphInstanceCreator()

Returns the engine's NewGraphInstanceCreator, or null if the engine does not support to create sub graph instances.

Returns:

the engine's NewGraphInstanceCreator, or null if the engine does not support to create sub graph instances.

registerInstanceEventListener

void registerInstanceEventListener(GraphInstanceEventListener listener)

Adds a GraphInstanceEventListener to the engine.

Parameters:

listener - listener to be added

registerWorkItemEventListener

void registerWorkItemEventListener(GraphWorkItemEventListener listener)

Adds a GraphWorkItemEventListener to the engine.

Parameters:

listener - listener to be added

registerNodeEventListener

void registerNodeEventListener(NodeEventListener listener)

Adds a NodeEventListener to the engine.

Parameters:

listener - listener to be added