gov.nasa.arc.brahms.vm.rt
Class VMWorkframeCtx

java.lang.Object
  gov.nasa.arc.brahms.common.rt.BrahmsObjectCtx
      gov.nasa.arc.brahms.common.rt.FrameCtx
          gov.nasa.arc.brahms.vm.rt.VMFrameCtx
              gov.nasa.arc.brahms.vm.rt.VMWorkframeCtx

All Implemented Interfaces:

IBrahmsObjectCtx, IFrameCtx, IRuntimeConstants, IWorkframeCtx, gov.nasa.arc.brahms.vm.events.IDiscreteEventData, gov.nasa.arc.brahms.vm.events.IDiscreteEventHandler, java.io.Serializable

public class VMWorkframeCtx
extends VMFrameCtx
implements IWorkframeCtx

The VMWorkframeCtx maintains the state for a workframe and has extensions for use in the virtual machine. In addition to keeping track of the state information as defined in the VMFrameCtx the workframe context also tracks the activity currently executed in the frame, the activities that have completed and the detectable contexts defining the detectables that were executed in the context of the workframe.

Version:

$Revision: 1.4 $ $Date: 2011/10/28 13:36:26 $ $Author: rvanhoof $

Author:

Ron van Hoof

See Also:

VMFrameCtx, Serialized Form

Field Summary

static java.lang.String	DETECTABLE property name used with DiscreteEvent to indicate a detectable causing a state change
static java.lang.String	IMPASSE_RESOLVING_BELIEF property name used with DiscreteEvent to indicate a belief resolving the impasse
static java.lang.String	INTERRUPTING_FRAME Property name used with DiscreteEvent to indicate an interrupting frame

Fields inherited from interface gov.nasa.arc.brahms.common.rt.IRuntimeConstants

ABORTED, ACTIVE, ACTIVITY, AVAILABLE, COMPLETED, CONSEQUENCE, ENDED, ENGINE, EXTERNAL_AGENT, FROM, IMPASSED, INITIAL, INTERRUPTED, JAVA_PROPERTY, sABORTED, sACTIVE, sAVAILABLE, sCOMPLETED, sENDED, sIMPASSED, sINTERRUPTED, sUNAVAILABLE, TO, TRANSFER, UNAVAILABLE

Constructor Summary

VMWorkframeCtx(VMWorkframe frame)
Constructor, creates a new context for the specified workframe.

VMWorkframeCtx(VMWorkframe frame, VMActiveInstanceCtx agent)
Constructor, creates a new context for the specified frame setting the specified agent as the agent working on frame.

Method Summary

void	addActiveDetectable(IDetectableCtx detectable) Adds the specified detectable as an active detectable to the list of active detectables.
void	addCompletedActivity(ActivityCtx act) Adds the specified activity as a completed activity to the list of completed activities.
protected void	doWork(long currentTime) Executes work up to the time higher then the time currently being executed.
java.util.ListIterator	getActiveDetectables() Returns the list of active detectables.
java.util.ListIterator	getCompletedActivities() Returns the list of completed activities.
ActivityCtx	getCurrentActivity() Returns the activity currently active in the workframe
VMWorkframeCtx	getLowestCurrentWork() Returns the workframe context lowest in the frame hierarchy using this workframe context as the starting point.
protected int	getPreviousStatus() Returns the previous status, the status the frame had before the current status.
int	getPriority() Returns the priority of the frame context.
boolean	handleDiscreteEvent(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Process the specified discrete event.
void	onAbort(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is aborted.
void	onComplete(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is to be completed.
void	onCompleteFinal(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context was completed by a detectable and all remaining consequences have been fired and their events processed.
void	onContinue(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is continued from an interrupt.
void	onContinueFromImpasse(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is continued from an impasse.
void	onEnd(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when a frame terminated under normal conditions meaning that there was nothing more to work on.
void	onImpasse(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is impassed.
void	onInterrupt(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is interrupted.
void	onStart(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt) Called when the frame context is started for the first time.
void	removeActiveDetectable(IDetectableCtx detectable) Removes the specified detectable as an active detectable from the list of active detectables.
void	removeCompletedActivity(ActivityCtx act) Removes the specified activity as a completed activity from the list of completed activities.
void	setCurrentActivity(ActivityCtx act) Sets the activity currently active in the workframe
void	setStatus(int status) Sets the frame's current status.
protected void	setTestEndCompositeActivity(boolean test) Sets the flag indicating whether or not this workframe should test if its current composite activity should be ended due to no more work being available.
protected void	updateDeltaEventTime(IActivityCtx activity, long deltaTime) Update the delta event time for the end activity event for the specified activity.

Methods inherited from class gov.nasa.arc.brahms.vm.rt.VMFrameCtx

addFrameStatusListener, fireStatusChanged, handleDiscreteEvent, onAvailable, onUnavailable, removeFrameStatusListener

Methods inherited from class gov.nasa.arc.brahms.common.rt.FrameCtx

addBinding, addFiredConsequence, getBinding, getBindings, getFiredConsequences, getPerformedBy, getPerformedIn, getState, getStatus, getTimeAvailable, removeBinding, removeFiredConsequence, setPerformedBy, setPerformedIn, setPriority, setState, setState, setTimeAvailable, toString

Methods inherited from class gov.nasa.arc.brahms.common.rt.BrahmsObjectCtx

addNote, getContextFor, getEndTime, getID, getNote, getNotes, getStartTime, removeNote, setContextFor, setEndTime, setID, setStartTime

Methods inherited from class java.lang.Object

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

Methods inherited from interface gov.nasa.arc.brahms.common.rt.IFrameCtx

addBinding, addFiredConsequence, getBinding, getBindings, getFiredConsequences, getPerformedBy, getPerformedIn, getState, getStatus, getTimeAvailable, removeBinding, removeFiredConsequence, setPerformedBy, setPerformedIn, setPriority, setState, setState, setTimeAvailable

Methods inherited from interface gov.nasa.arc.brahms.common.rt.IBrahmsObjectCtx

addNote, getContextFor, getEndTime, getID, getNote, getNotes, getStartTime, removeNote, setEndTime, setID, setStartTime

Field Detail

INTERRUPTING_FRAME

public static final java.lang.String INTERRUPTING_FRAME

Property name used with DiscreteEvent to indicate an interrupting frame

See Also:

Constant Field Values

DETECTABLE

public static final java.lang.String DETECTABLE

property name used with DiscreteEvent to indicate a detectable causing a state change

See Also:

Constant Field Values

IMPASSE_RESOLVING_BELIEF

public static final java.lang.String IMPASSE_RESOLVING_BELIEF

property name used with DiscreteEvent to indicate a belief resolving the impasse

See Also:

Constant Field Values

Constructor Detail

VMWorkframeCtx

public VMWorkframeCtx(VMWorkframe frame)

Constructor, creates a new context for the specified workframe.

Parameters:

frame - the Workframe for which this frame context is a context

VMWorkframeCtx

public VMWorkframeCtx(VMWorkframe frame,
                      VMActiveInstanceCtx agent)

Constructor, creates a new context for the specified frame setting the specified agent as the agent working on frame.

Parameters:

frame - the Workframe for which this frame context is a context

agent - the agent working on the frame

Method Detail

getPriority

public int getPriority()
                throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Returns the priority of the frame context. The priority is calculated by the virtual machine based on the priorities of its activities.

Specified by:

getPriority in interface IFrameCtx

Overrides:

getPriority in class FrameCtx

Returns:

int the frame context's priority

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if no priority is set

setTestEndCompositeActivity

protected void setTestEndCompositeActivity(boolean test)

Sets the flag indicating whether or not this workframe should test if its current composite activity should be ended due to no more work being available. This flag is set by the composite activity.

Parameters:

test - true if the test should be performed, false otherwise.

doWork

protected void doWork(long currentTime)

Executes work up to the time higher then the time currently being executed.

Specified by:

doWork in class VMFrameCtx

Parameters:

currentTime - the time at which and for which work can be executed

Throws:

VMError - if an unexpected error occurs in executing the work

setStatus

public void setStatus(int status)
               throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Sets the frame's current status.

Specified by:

setStatus in interface IFrameCtx

Overrides:

setStatus in class VMFrameCtx

Parameters:

status - the status of the frame context

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if status is an invalid status

See Also:

IRuntimeConstants.UNAVAILABLE, IRuntimeConstants.AVAILABLE, IRuntimeConstants.ACTIVE, IRuntimeConstants.INTERRUPTED, IRuntimeConstants.IMPASSED, IRuntimeConstants.ABORTED, IRuntimeConstants.COMPLETED, IRuntimeConstants.ENDED

getPreviousStatus

protected int getPreviousStatus()

Returns the previous status, the status the frame had before the current status. After the frame performed work the previous status is set to the current status to keep track of whether the frame is continuing its work or if it is continuing work after an interrupt.

Returns:

int the previous status of the frame context

See Also:

IRuntimeConstants.UNAVAILABLE, IRuntimeConstants.AVAILABLE, IRuntimeConstants.ACTIVE, IRuntimeConstants.INTERRUPTED, IRuntimeConstants.IMPASSED, IRuntimeConstants.ABORTED, IRuntimeConstants.COMPLETED, IRuntimeConstants.ENDED

setCurrentActivity

public void setCurrentActivity(ActivityCtx act)

Sets the activity currently active in the workframe

Specified by:

setCurrentActivity in interface IWorkframeCtx

Parameters:

act - the current activity (ActivityCtx)

getCurrentActivity

public ActivityCtx getCurrentActivity()

Returns the activity currently active in the workframe

Specified by:

getCurrentActivity in interface IWorkframeCtx

Returns:

ActivityCtx the current activity (ActivityCtx) of the workframe context, null if the workframe context has no activity active

getLowestCurrentWork

public VMWorkframeCtx getLowestCurrentWork()

Returns the workframe context lowest in the frame hierarchy using this workframe context as the starting point. This method returns the lowest current work in the current activity if the activity is a composite activity that has current work specified. If the current activity is not a composite activity or the composite activity has no current work then this workframe context is returned.

Returns:

VMWorkframeCtx the lowest current workframe context

addCompletedActivity

public void addCompletedActivity(ActivityCtx act)
                          throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Adds the specified activity as a completed activity to the list of completed activities.

Specified by:

addCompletedActivity in interface IWorkframeCtx

Parameters:

act - the ActivityCtx for the activity completed in the workframe

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if the activity is null

removeCompletedActivity

public void removeCompletedActivity(ActivityCtx act)
                             throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Removes the specified activity as a completed activity from the list of completed activities.

Specified by:

removeCompletedActivity in interface IWorkframeCtx

Parameters:

act - the ActivityCtx for the activity to be removed as a completed activity

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if the activity is null or no completed activities exist or the specified activity is not found

getCompletedActivities

public java.util.ListIterator getCompletedActivities()
                                              throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Returns the list of completed activities.

Specified by:

getCompletedActivities in interface IWorkframeCtx

Returns:

ListIterator the list of completed activities (ActivityCtx)

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if no completed activities exist

addActiveDetectable

public void addActiveDetectable(IDetectableCtx detectable)
                         throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Adds the specified detectable as an active detectable to the list of active detectables. An active detectable is actively checked while the workframe is active.

Specified by:

addActiveDetectable in interface IWorkframeCtx

Parameters:

detectable - the IDetectableCtx for the detectable active in the workframe

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if the detectable is null

removeActiveDetectable

public void removeActiveDetectable(IDetectableCtx detectable)
                            throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Removes the specified detectable as an active detectable from the list of active detectables.

Specified by:

removeActiveDetectable in interface IWorkframeCtx

Parameters:

detectable - the IDetectableCtx for the detectable to be removed as an active detectable

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if the detectable is null or no active detectables exist or the specified detectable is not found

getActiveDetectables

public java.util.ListIterator getActiveDetectables()
                                            throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Returns the list of active detectables.

Specified by:

getActiveDetectables in interface IWorkframeCtx

Returns:

ListIterator the list of active detectables (IDetectableCtx)

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if no active detectables exist

handleDiscreteEvent

public boolean handleDiscreteEvent(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Process the specified discrete event.

Specified by:

handleDiscreteEvent in interface gov.nasa.arc.brahms.vm.events.IDiscreteEventHandler

Overrides:

handleDiscreteEvent in class VMFrameCtx

Parameters:

evt - the DiscreteEvent to be processed.

Returns:

boolean true if the event could be processed, false if not

onStart

public void onStart(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is started for the first time.

Overrides:

onStart in class VMFrameCtx

Parameters:

evt - the DiscreteEvent that initiated the start of the frame

onEnd

public void onEnd(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when a frame terminated under normal conditions meaning that there was nothing more to work on.

Overrides:

onEnd in class VMFrameCtx

Parameters:

evt - the DiscreteEvent that initiated the end of the frame

onInterrupt

public void onInterrupt(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is interrupted. Sets the status and notifies the event notifier of the interruption.

Parameters:

evt - the DiscreteEvent that initiated the interruption of the frame

onContinue

public void onContinue(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is continued from an interrupt. Sets the status and notifies the event notifier of the continuation.

Parameters:

evt - the DiscreteEvent that initiated the continuation of the frame

onImpasse

public void onImpasse(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is impassed. Sets the status and notifies the event notifier of the impasse.

Parameters:

evt - the DiscreteEvent that initiated the impasse of the frame

onContinueFromImpasse

public void onContinueFromImpasse(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is continued from an impasse. Sets the status and notifies the event notifier of the continuation after the impasse. Continuation from an impasse means that the frame is moved from the state impasse to the state interrupted.

Parameters:

evt - the DiscreteEvent that initiated the continuation of the frame from an impasse

onAbort

public void onAbort(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is aborted. Sets the status and notifies the event notifier of the abort. An abort terminates the frame context immediately without completing any activities or consequences.

Parameters:

evt - the DiscreteEvent that initiated the abort of the frame

onComplete

public void onComplete(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context is to be completed. Sets the status and notifies the event notifier of the completion. Completion of a frame context causes the frame to terminate the current activity, skip over any remaining activities, but to fire all consequences following the terminated activity and that are listed in the frame.

Parameters:

evt - the DiscreteEvent that initiated the completion of the frame

onCompleteFinal

public void onCompleteFinal(gov.nasa.arc.brahms.vm.events.DiscreteEvent evt)

Called when the frame context was completed by a detectable and all remaining consequences have been fired and their events processed.

Parameters:

evt - the DiscreteEvent that initiated the completion of the frame

updateDeltaEventTime

protected void updateDeltaEventTime(IActivityCtx activity,
                                    long deltaTime)

Update the delta event time for the end activity event for the specified activity. This method can only be used while the events are still in the next event queue before they are asserted on the active instance's event queue. This method should only be used by activities onContinue. This method is currently only used by the move activities to correct the end time after a move has been interrupted and the agent had moved to a different location while the frame was interrupted.

Parameters:

activity - the activity for which to update the event

deltaTime - the new delta time