zeus.actors
Class ExecutionMonitor

java.lang.Object
  java.lang.Thread
      zeus.actors.ExecutionMonitor

All Implemented Interfaces:

java.lang.Runnable

public class ExecutionMonitor

extends java.lang.Thread

This component controls the invocation of the domain functions that implement the agent's task abilities. Domain functions are typically external program code or legacy systems that implement the methods of the ZeusTask interface. A domain function is invoked with the task's preconditions as its input arguments, and upon completion its declared effects will be passed back to the agent through this component.

Another important role of the Execution Monitor is to detect failure during the scheduled execution of a plan. This can occur for a number of reasons:

1. a resource reserved by an task might have been deleted,
2. an operator might begin execution but fail to complete for some reason,
3. an operator might successfully complete execution but return the wrong or incomplete results, or
4. some promised resource from another agent might not arrive on time

Should any of the above occur, the Execution Monitor will trigger remedial action, which may involve replanning.

Field Summary

protected AgentContext	context
private HSet[]	eventMonitor
protected boolean	monitoring
static int	TICK
static double	UPDATE_FRACTION

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

ExecutionMonitor()

ExecutionMonitor(AgentContext context)

Method Summary

void	addClockMonitor(ClockMonitor monitor, long type)
AgentContext	getAgentContext()
protected void	notifyMonitors(int tick, int event_type)
void	removeClockMonitor(ClockMonitor monitor, long type)
void	run()
void	stopMonitoring()

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getContextClassLoader, getName, getPriority, getThreadGroup, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setName, setPriority, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

TICK

public static final int TICK

See Also:

Constant Field Values

UPDATE_FRACTION

public static final double UPDATE_FRACTION

See Also:

Constant Field Values

eventMonitor

private HSet[] eventMonitor

monitoring

protected boolean monitoring

context

protected AgentContext context

Constructor Detail

ExecutionMonitor

public ExecutionMonitor()

ExecutionMonitor

public ExecutionMonitor(AgentContext context)

Method Detail

getAgentContext

public AgentContext getAgentContext()

stopMonitoring

public void stopMonitoring()

run

public void run()

addClockMonitor

public void addClockMonitor(ClockMonitor monitor,
                            long type)

removeClockMonitor

public void removeClockMonitor(ClockMonitor monitor,
                               long type)

notifyMonitors

protected void notifyMonitors(int tick,
                              int event_type)