com.xatkit.core

Class ExecutionService

java.lang.Object

org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter

com.xatkit.core.ExecutionService

All Implemented Interfaces:

org.eclipse.xtext.xbase.interpreter.IExpressionInterpreter

public class ExecutionService
extends org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter

A service that handles EventInstances and executes the corresponding RuntimeActions defined in the provided ExecutionModel.

This class defines Xatkit' execution logic: RuntimeEventProviders typically call the handleEventInstance(EventInstance, XatkitSession) method to process a retrieved EventInstance, and trigger the RuntimeActions that are associated to it in the ExecutionModel.

The ExecutionService is initialized by the XatkitCore instance, that loads the ExecutionModel and initializes the RuntimePlatformRegistry.

See Also:

EventInstance, XatkitCore

Field Summary

Fields

Modifier and Type	Field and Description
static String	MATCHED_EVENT_SESSION_KEY The XatkitSession key used to store the matched event.

Constructor Summary

Constructors

Constructor and Description
ExecutionService(com.xatkit.execution.ExecutionModel executionModel, RuntimePlatformRegistry runtimePlatformRegistry, Configuration configuration) Constructs a new ExecutionService based on the provided executionModel and runtimePlatformRegistry.

Method Summary

Modifier and Type	Method and Description
protected Object	doEvaluate(org.eclipse.xtext.xbase.XExpression expression, org.eclipse.xtext.xbase.interpreter.IEvaluationContext context, org.eclipse.xtext.util.CancelIndicator indicator) Evaluates the provided expression.
com.xatkit.execution.ExecutionModel	getExecutionModel() Returns the ExecutionModel associated to this ExecutionService.
protected ExecutorService	getExecutorService() Returns the ExecutorService used to process RuntimeActions.
RuntimePlatformRegistry	getRuntimePlatformRegistry() Returns the RuntimePlatformRegistry associated to this ExecutionService.
void	handleEventInstance(com.xatkit.intent.EventInstance eventInstance, XatkitSession session) Handles the provided eventInstance and executes the corresponding RuntimeActions defined in the ExecutionModel.
boolean	isShutdown() Returns whether the ExecutionService is shutdown.
void	shutdown() Shuts down the underlying ExecutorService.

Methods inherited from class org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter

_assignValueTo, _assignValueTo, _assignValueTo, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _doEvaluate, _invokeFeature, _invokeFeature, _invokeFeature, applyGetAndAssignOperator, assignValueTo, castToPrimitiveType, coerceArgumentType, createContext, eq, evaluate, evaluate, evaluateArgumentExpressions, evaluateGetAndAssign, featureCallField, getActualArguments, getActualReceiver, getClass, getClassFinder, getDefaultObjectValue, getJavaReflectAccess, getJavaType, getReceiver, internalEvaluate, invokeFeature, invokeOperation, invokeOperation, isGetAndAssign, isInstanceoOf, isType, resolveType, setClassLoader, setFeatureNameProvider, throwClassCastException, throwNullPointerException, translateJvmTypeToResult, wrapOrUnwrapArray

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MATCHED_EVENT_SESSION_KEY

public static final String MATCHED_EVENT_SESSION_KEY

The XatkitSession key used to store the matched event.

The value associated to this key is an EventInstance.

See Also:

Constant Field Values

Constructor Detail

ExecutionService

public ExecutionService(com.xatkit.execution.ExecutionModel executionModel,
                        RuntimePlatformRegistry runtimePlatformRegistry,
                        Configuration configuration)

Constructs a new ExecutionService based on the provided executionModel and runtimePlatformRegistry.

This constructor also takes care of resolving all the proxies in the provided ExecutionModel, ensuring that concurrent accesses of the model will not produce unexpected behaviors (see this post)

Parameters:

executionModel - the ExecutionModel representing the intent-to-action bindings to use

runtimePlatformRegistry - the RuntimePlatformRegistry used to create the RuntimeActions to execute

configuration - the Xatkit configuration

Throws:

NullPointerException - if the provided executionModel or runtimePlatformRegistry is null

Method Detail

getExecutorService

protected ExecutorService getExecutorService()

Returns the ExecutorService used to process RuntimeActions.

Note: this method is designed to ease testing, and should not be accessed by client applications. Manipulating XatkitCore's ExecutorService may create consistency issues on currently executed RuntimeActions.

Returns:

the ExecutorService used to process RuntimeActions

getExecutionModel

public com.xatkit.execution.ExecutionModel getExecutionModel()

Returns the ExecutionModel associated to this ExecutionService.

Returns:

the ExecutionModel associated to this ExecutionService

getRuntimePlatformRegistry

public RuntimePlatformRegistry getRuntimePlatformRegistry()

Returns the RuntimePlatformRegistry associated to this ExecutionService.

Returns:

the RuntimePlatformRegistry associated to this ExecutionService

handleEventInstance

public void handleEventInstance(com.xatkit.intent.EventInstance eventInstance,
                                XatkitSession session)

Handles the provided eventInstance and executes the corresponding RuntimeActions defined in the ExecutionModel.

This method creates an asynchronous task that retrieves the RuntimeActions to execute from the ExecutionModel, and executes them sequentially. Note that all the RuntimeActions are executed in the same Thread, in order to ensure that their pre-conditions are respected (i.e. the context variables defined by an action are available for the next ones).

Exceptions thrown from the computed RuntimeActions are logged and ignored, so the calling RuntimeEventProvider does not have to handle the exception, and can process the next event.

The created task also registers the output context values to the provided session, making them available for the computed actions.

Parameters:

eventInstance - the EventInstance to handle

session - the XatkitSession used to define and access context variables

Throws:

NullPointerException - if the provided eventInstance or session is null

See Also:

executeExecutionRule(ExecutionRule, XatkitSession)

doEvaluate

protected Object doEvaluate(org.eclipse.xtext.xbase.XExpression expression,
                            org.eclipse.xtext.xbase.interpreter.IEvaluationContext context,
                            org.eclipse.xtext.util.CancelIndicator indicator)

Evaluates the provided expression.

This methods delegates to the XbaseInterpreter the computation of all XExpressions, excepted XMemberFeatureCalls representing platform's action call. For these specific expressions the interpreter takes care of constructing the corresponding RuntimeAction, evaluates its parameters, and invoke it.

Overrides:

doEvaluate in class org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter

Parameters:

expression - the XExpression to evaluate

context - the IEvaluationContext containing the information already computed during the evaluation

indicator - the indicator

Returns:

the result of the evaluation

See Also:

executeRuntimeAction(RuntimeAction)

shutdown

public void shutdown()

Shuts down the underlying ExecutorService.

Shutting down the ExecutionService invalidates it and does not allow to process new RuntimeActions.

isShutdown

public boolean isShutdown()

Returns whether the ExecutionService is shutdown.

Returns:

whether the ExecutionService is shutdown