Reference

This section describes the underlying machinery of JANA. This is essentially a launchpad into Doxygen.

Main API

• JApplication: The main entry point into the program

• JObject: Data containers for specific results

• JEventSource : From a file or messaging producer, expose a stream of events. Each event is an aggregate of JObjects

• JFactory : Given an event, calculate a specific result, potentially calling other JFactories recursively to obtain any prereqs

• JEventProcessor: Run desired JFactories over the event stream, writing results to an output file or messaging consumer

Streaming Extensions

• JStreamingEventSource : A starting point for structured, composable streaming

• JTransport : An interface for a generic messaging transport

• JMessage: An interface for a stream buffer

User-facing utilities

• JParameter : Configure the behavior of components at runtime

• JLogger : Publish debugging information to standard out in a structured, convenient, threadsafe way

• JService : Share external (stateful) services such as calibration constants and magnetic field maps

• JCsvWriter : Conveniently debug a JFactory by writing its generated JObjects to CSV

Internal services

• JLoggingService : Furnish the user with a logger already configured for that particular component

• JParameterManager : Furnish the user with parameters extracted from command line flags and configuration files

Parallelism engine

• JProcessingController : The interface which any parallelism engine must adhere to

• JArrowProcessingController : The entry point into the “Arrow” engine

• JWorker : Contains the loop for each worker thread, along with startup/shutdown logic and encapsulated worker state.

• JScheduler : Contains the logic for giving a worker a new assignment