public override EPStatementStartResult StartInternal(
EPServicesContext services,
StatementContext statementContext,
bool isNewStatement,
bool isRecoveringStatement,
bool isRecoveringResilient)
{
var createDesc = _statementSpec.CreateVariableDesc;
VariableServiceUtil.CheckAlreadyDeclaredTable(createDesc.VariableName, services.TableService);
// Get assignment value
object value = null;
if (createDesc.Assignment != null)
{
// Evaluate assignment expression
StreamTypeService typeService = new StreamTypeServiceImpl(
new EventType[0], new string[0], new bool[0], services.EngineURI, false);
var evaluatorContextStmt = new ExprEvaluatorContextStatement(statementContext, false);
var validationContext = new ExprValidationContext(
typeService,
statementContext.MethodResolutionService, null,
statementContext.SchedulingService,
statementContext.VariableService,
statementContext.TableService, evaluatorContextStmt,
statementContext.EventAdapterService,
statementContext.StatementName, statementContext.StatementId,
statementContext.Annotations,
statementContext.ContextDescriptor,
statementContext.ScriptingService,
false, false, false, false, null, false);
var validated = ExprNodeUtility.GetValidatedSubtree(
ExprNodeOrigin.VARIABLEASSIGN, createDesc.Assignment, validationContext);
value = validated.ExprEvaluator.Evaluate(new EvaluateParams(null, true, evaluatorContextStmt));
}
// Create variable
try
{
services.VariableService.CreateNewVariable(
_statementSpec.OptionalContextName, createDesc.VariableName, createDesc.VariableType, createDesc.IsConstant,
createDesc.IsArray, createDesc.IsArrayOfPrimitive, value, services.EngineImportService);
}
catch (VariableExistsException ex)
{
// for new statement we don't allow creating the same variable
if (isNewStatement)
{
throw new ExprValidationException("Cannot create variable: " + ex.Message, ex);
}
}
catch (VariableDeclarationException ex)
{
throw new ExprValidationException("Cannot create variable: " + ex.Message, ex);
}
var destroyMethod = new EPStatementDestroyCallbackList();
destroyMethod.AddCallback(new ProxyDestroyCallback(() =>
{
try
{
services.StatementVariableRefService.RemoveReferencesStatement(statementContext.StatementName);
}
catch (Exception ex)
{
Log.Error("Error removing variable '" + createDesc.VariableName + "': " + ex.Message);
}
}));
var stopMethod = new ProxyEPStatementStopMethod(() => { });
var variableMetaData = services.VariableService.GetVariableMetaData(createDesc.VariableName);
Viewable outputView;
var eventType = CreateVariableView.GetEventType(
statementContext.StatementId, services.EventAdapterService, variableMetaData);
var contextFactory =
new StatementAgentInstanceFactoryCreateVariable(
createDesc, _statementSpec, statementContext, services, variableMetaData, eventType);
statementContext.StatementAgentInstanceFactory = contextFactory;
if (_statementSpec.OptionalContextName != null)
{
var mergeView = new ContextMergeView(eventType);
outputView = mergeView;
var statement =
new ContextManagedStatementCreateVariableDesc(_statementSpec, statementContext, mergeView, contextFactory);
services.ContextManagementService.AddStatement(
_statementSpec.OptionalContextName, statement, isRecoveringResilient);
var contextManagementService = services.ContextManagementService;
destroyMethod.AddCallback(new ProxyDestroyCallback(() => contextManagementService.DestroyedStatement(
_statementSpec.OptionalContextName, statementContext.StatementName,
statementContext.StatementId)));
}
else
{
var resultOfStart =
(StatementAgentInstanceFactoryCreateVariableResult)
contextFactory.NewContext(GetDefaultAgentInstanceContext(statementContext), isRecoveringResilient);
outputView = resultOfStart.FinalView;
if (statementContext.StatementExtensionServicesContext != null &&
statementContext.StatementExtensionServicesContext.StmtResources != null)
{
var holder =
statementContext.StatementExtensionServicesContext.ExtractStatementResourceHolder(resultOfStart);
statementContext.StatementExtensionServicesContext.StmtResources.Unpartitioned = holder;
statementContext.StatementExtensionServicesContext.PostProcessStart(resultOfStart, isRecoveringResilient);
}
}
services.StatementVariableRefService.AddReferences(
statementContext.StatementName, Collections.SingletonList(createDesc.VariableName), null);
return(new EPStatementStartResult(outputView, stopMethod, destroyMethod));
}
public override EPStatementStartResult StartInternal(EPServicesContext services, StatementContext statementContext, bool isNewStatement, bool isRecoveringStatement, bool isRecoveringResilient)
{
var createDesc = StatementSpec.CreateVariableDesc;
VariableServiceUtil.CheckAlreadyDeclaredTable(createDesc.VariableName, services.TableService);
// Get assignment value
Object value = null;
if (createDesc.Assignment != null)
{
// Evaluate assignment expression
var typeService = new StreamTypeServiceImpl(new EventType[0], new String[0], new bool[0], services.EngineURI, false);
var evaluatorContextStmt = new ExprEvaluatorContextStatement(statementContext, false);
var validationContext = new ExprValidationContext(
typeService,
statementContext.MethodResolutionService, null,
statementContext.SchedulingService,
statementContext.VariableService,
statementContext.TableService, evaluatorContextStmt,
statementContext.EventAdapterService,
statementContext.StatementName,
statementContext.StatementId,
statementContext.Annotations,
statementContext.ContextDescriptor,
statementContext.ScriptingService,
false, false, false, false, null, false);
var validated = ExprNodeUtility.GetValidatedSubtree(ExprNodeOrigin.VARIABLEASSIGN, createDesc.Assignment, validationContext);
value = validated.ExprEvaluator.Evaluate(new EvaluateParams(null, true, evaluatorContextStmt));
}
// Create variable
try
{
services.VariableService.CreateNewVariable(
StatementSpec.OptionalContextName,
createDesc.VariableName,
createDesc.VariableType,
createDesc.IsConstant,
createDesc.IsArray,
createDesc.IsArrayOfPrimitive,
value,
services.EngineImportService);
}
catch (VariableExistsException ex)
{
// for new statement we don't allow creating the same variable
if (isNewStatement)
{
throw new ExprValidationException("Cannot create variable: " + ex.Message, ex);
}
}
catch (VariableDeclarationException ex)
{
throw new ExprValidationException("Cannot create variable: " + ex.Message, ex);
}
var destroyMethod = new EPStatementDestroyCallbackList();
destroyMethod.AddCallback(
() =>
{
try
{
services.StatementVariableRefService.RemoveReferencesStatement(statementContext.StatementName);
}
catch (Exception ex)
{
Log.Error("Error removing variable '" + createDesc.VariableName + "': " + ex.Message);
}
});
var stopMethod = new EPStatementStopMethod(() => { });
VariableMetaData variableMetaData = services.VariableService.GetVariableMetaData(createDesc.VariableName);
Viewable outputView;
if (StatementSpec.OptionalContextName != null)
{
EventType eventType = CreateVariableView.GetEventType(statementContext.StatementId, services.EventAdapterService, variableMetaData);
var contextFactory = new StatementAgentInstanceFactoryCreateVariable(statementContext, services, variableMetaData, eventType);
var mergeView = new ContextMergeView(eventType);
outputView = mergeView;
var statement = new ContextManagedStatementCreateVariableDesc(StatementSpec, statementContext, mergeView, contextFactory);
services.ContextManagementService.AddStatement(StatementSpec.OptionalContextName, statement, isRecoveringResilient);
ContextManagementService contextManagementService = services.ContextManagementService;
destroyMethod.AddCallback(() => contextManagementService.DestroyedStatement(StatementSpec.OptionalContextName, statementContext.StatementName, statementContext.StatementId));
}
else
{
// allocate
services.VariableService.AllocateVariableState(createDesc.VariableName, VariableServiceConstants.NOCONTEXT_AGENTINSTANCEID, statementContext.StatementExtensionServicesContext);
var createView = new CreateVariableView(statementContext.StatementId, services.EventAdapterService, services.VariableService, createDesc.VariableName, statementContext.StatementResultService);
services.VariableService.RegisterCallback(createDesc.VariableName, 0, createView.Update);
statementContext.StatementStopService.StatementStopped +=
() => services.VariableService.UnregisterCallback(createDesc.VariableName, 0, createView.Update);
// Create result set processor, use wildcard selection
StatementSpec.SelectClauseSpec.SetSelectExprList(new SelectClauseElementWildcard());
StatementSpec.SelectStreamDirEnum = SelectClauseStreamSelectorEnum.RSTREAM_ISTREAM_BOTH;
StreamTypeService typeService = new StreamTypeServiceImpl(new EventType[] { createView.EventType }, new String[] { "create_variable" }, new bool[] { true }, services.EngineURI, false);
var agentInstanceContext = GetDefaultAgentInstanceContext(statementContext);
var resultSetProcessorPrototype = ResultSetProcessorFactoryFactory.GetProcessorPrototype(
StatementSpec, statementContext, typeService, null, new bool[0], true, ContextPropertyRegistryImpl.EMPTY_REGISTRY, null, services.ConfigSnapshot);
var resultSetProcessor = EPStatementStartMethodHelperAssignExpr.GetAssignResultSetProcessor(agentInstanceContext, resultSetProcessorPrototype);
// Attach output view
var outputViewFactory = OutputProcessViewFactoryFactory.Make(StatementSpec, services.InternalEventRouter, agentInstanceContext.StatementContext, resultSetProcessor.ResultEventType, null, services.TableService, resultSetProcessorPrototype.ResultSetProcessorFactory.ResultSetProcessorType);
var outputViewBase = outputViewFactory.MakeView(resultSetProcessor, agentInstanceContext);
createView.AddView(outputViewBase);
outputView = outputViewBase;
}
services.StatementVariableRefService.AddReferences(statementContext.StatementName, Collections.SingletonList(createDesc.VariableName), null);
return(new EPStatementStartResult(outputView, stopMethod, destroyMethod.Destroy));
}
