final List<StopCallback> stopCallbacks = new LinkedList<StopCallback>();
final EPStatementStopMethod stopMethod = new EPStatementStopMethodImpl(statementContext, stopCallbacks);
// determine context
final String contextName = statementSpec.getOptionalContextName();
final ContextPropertyRegistry contextPropertyRegistry = (contextName != null) ? services.getContextManagementService().getContextDescriptor(contextName).getContextPropertyRegistry() : null;
// Determine stream names for each stream - some streams may not have a name given
String[] streamNames = EPStatementStartMethodHelperUtil.determineStreamNames(statementSpec.getStreamSpecs());
int numStreams = streamNames.length;
final boolean isJoin = statementSpec.getStreamSpecs().size() > 1;