JStreamingEventSource is a class template which simplifies streaming events into JANA. More...
#include <JStreamingEventSource.h>
Public Member Functions | |
| JStreamingEventSource (std::unique_ptr< JTransport > &&transport) | |
| The constructor requires a unique pointer to a JTransport implementation. More... | |
| void | Open () override |
| Open delegates down to the transport, which will open a network socket or similar. | |
| Result | Emit (JEvent &event) override |
| GetEvent attempts to receive a JEventMessage. More... | |
 Public Member Functions inherited from JEventSource | |
| JEventSource (std::string resource_name, JApplication *app=nullptr) | |
| virtual void | Init () |
| virtual void | Preprocess (const JEvent &) const |
| For work that should be done in parallel on a JEvent, but is tightly coupled to the JEventSource for some reason. More... | |
| virtual void | FinishEvent (JEvent &) |
FinishEvent is used to notify the JEventSource that an event has been completely processed. More... | |
| virtual void | Close () |
Close is called by JANA when it is finished accepting events from this event source. More... | |
| virtual void | GetEvent (std::shared_ptr< JEvent >) |
GetEvent is called by JANA in order to emit a fresh event into the stream. More... | |
| virtual bool | GetObjects (const std::shared_ptr< const JEvent > &, JFactory *) |
GetObjects was historically used for lazily unpacking data from a JEvent and putting it into a "dummy" JFactory. More... | |
| std::string | GetResourceName () const |
| uint64_t | GetEventCount () const |
| uint64_t | GetEmittedEventCount () const |
| uint64_t | GetFinishedEventCount () const |
| virtual std::string | GetType () const |
| std::string | GetName () const |
| bool | IsGetObjectsEnabled () const |
| bool | IsFinishEventEnabled () const |
| bool | IsPreprocessEnabled () const |
| uint64_t | GetNSkip () |
| uint64_t | GetNEvents () |
| virtual std::string | GetVDescription () const |
| Optional for getting description via source rather than JEventSourceGenerator. | |
| void | SetResourceName (std::string resource_name) |
| void | EnableFinishEvent (bool enable=true) |
| EnableFinishEvent() is intended to be called by the user in the constructor in order to tell JANA to call the provided FinishEvent method after all JEventProcessors have finished with a given event. More... | |
| void | EnableGetObjects (bool enable=true) |
| void | EnablePreprocess (bool enable=true) |
| void | SetNEvents (uint64_t nevents) |
| void | SetNSkip (uint64_t nskip) |
| void | DoInitialize () |
| virtual void | DoInit () |
| void | DoOpen (bool with_lock=true) |
| void | DoClose (bool with_lock=true) |
| Result | DoNext (std::shared_ptr< JEvent > event) |
| Result | DoNextCompatibility (std::shared_ptr< JEvent > event) |
| void | DoFinish (JEvent &event) |
| void | Summarize (JComponentSummary &summary) const override |
| Public Member Functions inherited from jana::components::JComponent | |
| void | SetLevel (JEventLevel level) |
| void | SetCallbackStyle (CallbackStyle style) |
| void | SetPrefix (std::string prefix) |
| void | SetTypeName (std::string type_name) |
| For convenience, we provide a NAME_OF_THIS macro so that the user doesn't have to store the type name as a string, because that could get out of sync if automatic refactoring tools are used. | |
| JApplication * | GetApplication () const |
| JLogger & | GetLogger () |
| std::string | GetPrefix () const |
| JEventLevel | GetLevel () const |
| std::string | GetLoggerName () const |
| std::string | GetPluginName () const |
| void | SetLoggerName (std::string logger_name) |
| void | SetPluginName (std::string plugin_name) |
| std::string | GetTypeName () const |
| CallbackStyle | GetCallbackStyle () const |
| Status | GetStatus () const |
| void | SetApplication (JApplication *app) |
| void | SetLogger (JLogger logger) |
| template<typename F > | |
| void | CallWithJExceptionWrapper (std::string func_name, F func) |
| void | RegisterParameter (ParameterBase *parameter) |
| void | RegisterService (ServiceBase *service) |
| void | ConfigureAllParameters (std::map< std::string, std::string > fields) |
Static Public Member Functions | |
| static std::string | GetDescription () |
Additional Inherited Members | |
| Public Types inherited from JEventSource | |
| enum class | Result { Success , FailureTryAgain , FailureFinished } |
| Result describes what happened the last time a GetEvent() was attempted. More... | |
| enum class | RETURN_STATUS { kSUCCESS , kNO_MORE_EVENTS , kBUSY , kTRY_AGAIN , kERROR , kUNKNOWN } |
| The user is supposed to throw RETURN_STATUS::kNO_MORE_EVENTS or kBUSY from GetEvent() | |
| Public Types inherited from jana::components::JComponent | |
| enum class | Status { Uninitialized , Initialized , Opened , Closed , Finalized } |
| enum class | CallbackStyle { LegacyMode , ExpertMode , DeclarativeMode } |
| Protected Member Functions inherited from jana::components::JHasOutputs | |
| void | RegisterOutput (OutputBase *output) |
| Protected Attributes inherited from jana::components::JComponent | |
| std::vector< ParameterBase * > | m_parameters |
| std::vector< ServiceBase * > | m_services |
| JEventLevel | m_level = JEventLevel::PhysicsEvent |
| CallbackStyle | m_callback_style = CallbackStyle::LegacyMode |
| std::string | m_prefix |
| std::string | m_plugin_name |
| std::string | m_logger_name |
| std::string | m_type_name |
| Status | m_status = Status::Uninitialized |
| std::mutex | m_mutex |
| JApplication * | m_app = nullptr |
| JLogger | m_logger |
| Protected Attributes inherited from jana::components::JHasOutputs | |
| std::vector< OutputBase * > | m_outputs |
Detailed Description
template<class MessageT>
class JStreamingEventSource< MessageT >
JStreamingEventSource is a class template which simplifies streaming events into JANA.
JStreamingEventSource makes it convenient to stream existing events into JANA by handling transport and message format as separate, orthogonal concerns. The user need only implement classes satisfying the JTransport and JEventMessage interfaces, and then they get a JStreamingEventSource 'for free'.
JStreamingEventSource<T> is templated on some message type T, which is a subclass of JEventMessage. This is needed so that it can construct new message objects of the appropriate subclass. As a result, JStreamingEventSource<T> only emits JEvents containing JEventMessages of type T, which means that every message produced upstream must be compatible with that message format. This shouldn't be a problem: it is always possible to make the message format more flexible, and any associated complexity is fundamentally a property of the message format anyway. However, if we are using JStreamingEventSource, it is essential that each message corresponds to one JEvent.
The JStreamingEventSource owns its JTransport, but passes ownership of each JMessage to its enclosing JEvent.
Constructor & Destructor Documentation
◆ JStreamingEventSource()
|
inlineexplicit |
The constructor requires a unique pointer to a JTransport implementation.
This is a reasonable assumption to make because each JEventSource already corresponds to some unique resource. JStreamingEventSource should be free to destroy its transport object whenever it likes, so try to keep the JTransport free of weird shared state.
Member Function Documentation
◆ Emit()
|
inlineoverridevirtual |
GetEvent attempts to receive a JEventMessage.
If it succeeds, it inserts it into the JEvent and sets the event number and run number appropriately.
Reimplemented from JEventSource.
The documentation for this class was generated from the following file:
- JStreamingEventSource.h
