Detailed Description

Performs a computation on input events to produce output events.

This is the direct descendant of Processor, and probably the one you'll want to inherit from when creating your own processors. While Processor takes care of input and output queues, SynchronousProcessor also implements Pullables and Pushables. These take care of collecting input events, waiting until one new event is received from all input traces before triggering the computation, pulling and buffering events from all outputs when either of the Pullables is being called, etc.

The only thing that is left undefined is what to do when new input events have been received from all input traces. This is the task of abstract method compute(Object[], Queue), which descendants of this class must implement.

In early versions of the library, this class was called SingleProcessor.

Author: Sylvain Hallé

Since: 0.1

Definition at line 50 of file SynchronousProcessor.java.

Classes
class	InputPushable
	Implementation of a `Pushable` for a single processor. More...
class	OutputPullable
	Implementation of a `Pullable` for a single processor. More...

Public Member Functions
	SynchronousProcessor (int in_arity, int out_arity)
	Initializes a processor.
Pushable	getPushableInput (int index)
	Returns the `Pushable` corresponding to the processor's i-th input trace.
Pullable	getPullableOutput (int index)
	Returns the `Pullable` corresponding to the processor's i-th output trace.
final SynchronousProcessor	setEventTracker (EventTracker tracker)
	Associates an event tracker to this processor.
Public Member Functions inherited from ca.uqac.lif.cep.Processor
	Processor (int in_arity, int out_arity)
	Initializes a processor.
final Object	getContext (String key)
	Retrieves an object from the processor's context.
Context	getContext ()
	Gets the context associated to this object.
void	setContext (String key, Object value)
	Adds an object to the object's context.
void	setContext (Context context)
	Adds a complete context to this object.
final int	hashCode ()
	Implementation of `hashCode()` specific to processors.
final boolean	equals (Object o)
	Implementation of `equals()` specific to processors.
final int	getId ()
	Fetches the processor instance's unique ID.
void	reset ()
	Resets the processor.
final Pushable	getPushableInput ()
	Returns the `Pushable` corresponding to the processor's first input trace.
final Pullable	getPullableOutput ()
	Returns the `Pullable` corresponding to the processor's first output trace.
void	setPullableInput (int i, Pullable p)
	Assigns a `Pullable` to the processor's i-th input.
Pullable	getPullableInput (int i)
	Returns the `Pullable` corresponding to the processor's i-th input.
void	setPushableOutput (int i, Pushable p)
	Assigns a `Pushable` to the processor's i-th output.
Pushable	getPushableOutput (int i)
	Retrieves the `Pushable` associated to the processor's i-th output.
final int	getInputArity ()
	Returns the processor's input arity.
final int	getOutputArity ()
	Returns the processor's output arity.
void	duplicateInto (Processor p)
	Copies the contents and state of the current processor into another.
final Set< Class<?> >	getInputType (int index)
	Gets the type of events the processor accepts for its i-th input trace.
void	getInputTypesFor (Set< Class<?> > classes, int index)
	Populates the set of classes accepted by the processor for its i-th input.
Class<?>	getOutputType (int index)
	Returns the type of the events produced by the processor for its i-th output.
void	start ()
	Starts the processor.
void	stop ()
	Stops the processor.
final EventTracker	getEventTracker ()
	Gets the instance of event tracker associated to this processor.
void	associateToInput (int in_stream_index, int in_stream_pos, int out_stream_index, int out_stream_pos)
	Associates an input event to an output event.
void	associateTo (NodeFunction f, int out_stream_index, int out_stream_pos)
	Associates a node function to a particular event of processor's output stream.
void	associateToOutput (int in_stream_index, int in_stream_pos, int out_stream_index, int out_stream_pos)
	Associates an input event to an output event.
final int	getInputCount ()
	Gets the number of event fronts received so far by this processor.
final int	getOutputCount ()
	Gets the number of event fronts produced so far by this processor.
final Object	print (ObjectPrinter<?> printer) throws ProcessorException
	Prints the contents of this processor into an object printer.
final Processor	read (ObjectReader<?> reader, Object o) throws ProcessorException
	Reads the content of a processor from a serialized object.
final Processor	duplicate ()
	Duplicates an object and sets it to its initial state.
void	copyInputQueue (int index, Collection< Object > to)
	Copies the content of one of the processor's input queue to a collection.
void	copyOutputQueue (int index, Collection< Object > to)
	Copies the content of one of the processor's output queue to a collection.
abstract Processor	duplicate (boolean with_state)
	Duplicates an object.
Processor	or (Processor p)
	Connects the first output pipe of this processor to the first input pipe of another processor.
Processor	or (CallAfterConnect c)
	Operates similar to `or(Processor)`, but also calls a method after the connection has been established.
Processor	or (SelectedInputPipe p)
	Connects the output at index 0 of the current processor to the input of another processor.
PipeSelector	getAt (int index)
	Gets the `PipeSelector` object corresponding to the processor's input or output pipe for a given index.
Pushable	rightShift (int index)
Pullable	leftShift (int index)
Queue< Object >	getInputQueue (int index)
	Gets the content of the processor's input queue at a given index.
Queue< Object >	getOutputQueue (int index)
	Gets the content of the processor's output queue at a given index.

Protected Member Functions
abstract boolean	compute (Object[] inputs, Queue< Object[]> outputs)
	Computes one or more output events from its input events.
Protected Member Functions inherited from ca.uqac.lif.cep.Processor
boolean	allNotifiedEndOfTrace ()
	Determines if all the upstream pushables have sent the end of trace notification.
final Context	newContext ()
	Creates a new empty context map.
boolean	onEndOfTrace (Queue< Object[]> outputs) throws ProcessorException
	Allows to describe a specific behavior when the trace of input fronts has reached its end.
Object	printState ()
	Produces an object that represents the state of the current processor.
Processor	readState (Object o)
	Reads the state of a processor and uses it to create a new instance.

Protected Attributes
final transient Queue< Object[]>	m_tempQueue
	A queue object that will be passed to the `compute(Object[], Queue)` method.
final transient Pushable[]	m_inputPushables
	An array of input pushables.
transient Pullable[]	m_outputPullables
	An array of output pullables.
Protected Attributes inherited from ca.uqac.lif.cep.Processor
int	m_inputArity
	The processor's input arity, i.e.
int	m_outputArity
	The processor's output arity, i.e.
transient Queue< Object >[]	m_inputQueues
	An array of input event queues.
transient EventTracker	m_eventTracker = null
	An object that keeps track of the relationship between input and output events.
transient Queue< Object >[]	m_outputQueues
	An array of output event queues.
transient Pullable[]	m_inputPullables
	An array of `Pullable`s, one for each input trace this processor receives.
transient Pushable[]	m_outputPushables
	An array of `Pushable`s, one for each output trace this processor produces.
int	m_inputCount = 0
	A counter incremented upon each input front processed.
int	m_outputCount = 0
	A counter incremented upon each output front processed.
Context	m_context = null
	The context in which the processor is instantiated.
boolean[]	m_hasBeenNotifiedOfEndOfTrace
	Indicates whether the processor has been notified of the end of trace or not.
boolean	m_notifiedEndOfTraceDownstream
	Indicates whether the processor has notified the end of the trace to the downstream processors it is connected to.

Additional Inherited Members
Static Public Member Functions inherited from ca.uqac.lif.cep.Processor
static boolean	allNull (Object[] v)
	Checks if all objects in the array are null.
static Queue< Object[]>	getEmptyQueue ()
	Gets an instance of an empty event queue.
static void	startAll (Processor ... procs)
	Starts all processors given as an argument.
static void	stopAll (Processor ... procs)
	Stops all processors given as an argument.
static List< ProvenanceNode >	getLeaves (ProvenanceNode root)
	Gets the leaves of a provenance tree.
Static Public Attributes inherited from ca.uqac.lif.cep.Processor
static final transient String	s_versionString = "0.11.2"
	A string used to identify the program's version.
static final transient int	MAX_PULL_RETRIES = 10000000
	Number of times the `Pullable#hasNext()` method tries to produce an output from the input before giving up.
Static Protected Member Functions inherited from ca.uqac.lif.cep.Processor
static void	getLeaves (ProvenanceNode root, List< ProvenanceNode > leaves)
	Accumulates the leaves of a provenance tree in a list.

Constructor & Destructor Documentation

◆ SynchronousProcessor()

ca.uqac.lif.cep.SynchronousProcessor.SynchronousProcessor	(	int	in_arity,
		int	out_arity )

Initializes a processor.

Parameters

in_arity	The input arity
out_arity	The output arity

Definition at line 76 of file SynchronousProcessor.java.

Member Function Documentation

◆ compute()

abstract boolean ca.uqac.lif.cep.SynchronousProcessor.compute	(	Object[]	inputs,
		Queue< Object[]>	outputs )

abstractprotected

Computes one or more output events from its input events.

Parameters

inputs	An array of input events; its length corresponds to the processor's input arity
outputs	A queue of arrays of objects. The processor should push arrays into this queue for every output front it produces. The size of each array should be equal to the processor's output arity, although this is not enforced.

Returns: true if this processor may output other events in the future, false otherwise

◆ getPullableOutput()

Pullable ca.uqac.lif.cep.SynchronousProcessor.getPullableOutput ( int index )

Returns the Pullable corresponding to the processor's i-th output trace.

Parameters

index The index. Should be between 0 and the processor's output arity - 1 (since indices start at 0).

Returns: The pullable if the index is within the appropriate range, null otherwise.

Reimplemented from ca.uqac.lif.cep.Processor.

Reimplemented in ca.uqac.lif.cep.io.ReadInputStream, ca.uqac.lif.cep.UniformProcessor, and ca.uqac.lif.cep.util.Lists.TimePack.

Definition at line 95 of file SynchronousProcessor.java.

◆ getPushableInput()

Pushable ca.uqac.lif.cep.SynchronousProcessor.getPushableInput ( int index )

Returns the Pushable corresponding to the processor's i-th input trace.

Parameters

index The index. Should be between 0 and the processor's input arity - 1 (since indices start at 0).

Returns: The pushable if the index is within the appropriate range. Outside of the range,

Reimplemented from ca.uqac.lif.cep.Processor.

Reimplemented in ca.uqac.lif.cep.UniformProcessor.

Definition at line 85 of file SynchronousProcessor.java.

◆ setEventTracker()

final SynchronousProcessor ca.uqac.lif.cep.SynchronousProcessor.setEventTracker ( EventTracker tracker )

Associates an event tracker to this processor.

Parameters

tracker The event tracker, or null to remove the association to an existing tracker

Returns: This processor

Reimplemented from ca.uqac.lif.cep.Processor.

Definition at line 583 of file SynchronousProcessor.java.

Member Data Documentation

◆ m_inputPushables

final transient Pushable [] ca.uqac.lif.cep.SynchronousProcessor.m_inputPushables

protected

An array of input pushables.

Definition at line 61 of file SynchronousProcessor.java.

◆ m_outputPullables

transient Pullable [] ca.uqac.lif.cep.SynchronousProcessor.m_outputPullables

protected

An array of output pullables.

Definition at line 66 of file SynchronousProcessor.java.

◆ m_tempQueue

final transient Queue<Object[]> ca.uqac.lif.cep.SynchronousProcessor.m_tempQueue

protected

A queue object that will be passed to the compute(Object[], Queue) method.

Definition at line 56 of file SynchronousProcessor.java.

The documentation for this class was generated from the following file:

/home/sylvain/Workspaces/beepbeep/core/src/ca/uqac/lif/cep/SynchronousProcessor.java

Detailed Description

Classes

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ SynchronousProcessor()

Member Function Documentation

◆ compute()

◆ getPullableOutput()

◆ getPushableInput()

◆ setEventTracker()

Member Data Documentation

◆ m_inputPushables

◆ m_outputPullables

◆ m_tempQueue