gov.nasa.arc.brahms.common.rt
Class UnavailableCtx

java.lang.Object
  gov.nasa.arc.brahms.common.rt.BrahmsObjectCtx
      gov.nasa.arc.brahms.common.rt.FrameStateCtx
          gov.nasa.arc.brahms.common.rt.UnavailableCtx

All Implemented Interfaces:

IBrahmsObjectCtx, IRuntimeConstants, java.io.Serializable

public class UnavailableCtx
extends FrameStateCtx

The UnavailableCtx manages information about the unavailable state of a frame. The unavailable state is entered by a frame when the frame was available and one or more of its preconditions evaluated to false due to a change in the belief or fact set. This context maintains when the frame enters the unavailable state and when the frame leaves the unavailable state. This context also defines the contexts of the beliefs or facts (statement) that caused a precondition to evaluate to false.

Version:

28 July 2000

Author:

Ron van Hoof

See Also:

FrameStateCtx, Serialized Form

Field Summary

static byte	DETECTABLE Indicates as the cause for unavailability the end of a composite activity caused by a detectable (abort or complete)
static byte	RETRACTION Indicates as the cause for unavailability a retracted statement

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

UnavailableCtx(IFrameCtx frame)
Constructor, creates a new UnavailableCtx for the specified frame

Method Summary

void	addCausingStatement(StatementCtx statement) Adds the specified statement (belief or fact) as a statement causing a precondition to evaluate to false.
byte	getCause() Returns the cause of the unavailability, either RETRACTION when a statement was retracted causing the frame to become unavailable or DETECTABLE when a composite activity was aborted or completed by a detectable.
DetectableCtx	getCausingDetectable() Returns the detectable causing the unavailability of the frame.
java.util.Enumeration	getCausingStatements() Returns a list of all the statements (facts or beliefs) causing a precondition to evaluate to false.
int	getState() Returns the state identifier
java.lang.String	getStateName() Returns the name of the state
void	removeCausingStatement(StatementCtx statement) Removes the specified statement (belief or fact) as a statement causing a precondition to evaluate to false.
void	setCause(byte cause) Sets the cause of the unavailability, either RETRACTION when a statement was retracted causing the frame to become unavailable or DETECTABLE when a composite activity was aborted or completed by a detectable.
void	setCausingDetectable(DetectableCtx detectable) Sets the detectable causing the unavailability of the frame.

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

getFrame, getNextFrameState, getPreviousFrameState, setFrame, setNextFrameState, setPreviousFrameState

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, toString, wait, wait, wait

Field Detail

RETRACTION

public static final byte RETRACTION

Indicates as the cause for unavailability a retracted statement

See Also:

Constant Field Values

DETECTABLE

public static final byte DETECTABLE

Indicates as the cause for unavailability the end of a composite activity caused by a detectable (abort or complete)

See Also:

Constant Field Values

Constructor Detail

UnavailableCtx

public UnavailableCtx(IFrameCtx frame)
               throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Constructor, creates a new UnavailableCtx for the specified frame

Parameters:

frame - the IFrameCtx that is set to unavailable

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if frame specified is null

Method Detail

getState

public int getState()

Returns the state identifier

Overrides:

getState in class FrameStateCtx

Returns:

int the state id

getStateName

public java.lang.String getStateName()

Returns the name of the state

Overrides:

getStateName in class FrameStateCtx

Returns:

String the name of the state

setCause

public void setCause(byte cause)
              throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Sets the cause of the unavailability, either RETRACTION when a statement was retracted causing the frame to become unavailable or DETECTABLE when a composite activity was aborted or completed by a detectable.

Parameters:

cause - the cause for the unavailability

Throws:

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

See Also:

RETRACTION, DETECTABLE

getCause

public byte getCause()
              throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Returns the cause of the unavailability, either RETRACTION when a statement was retracted causing the frame to become unavailable or DETECTABLE when a composite activity was aborted or completed by a detectable. The methods getCausingStatements or getCausingDetectable provide the detailed information for the cause.

Parameters:

cause - the cause for the unavailability

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if no cause is specified

See Also:

RETRACTION, DETECTABLE, getCausingStatements(), getCausingDetectable()

addCausingStatement

public void addCausingStatement(StatementCtx statement)
                         throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Adds the specified statement (belief or fact) as a statement causing a precondition to evaluate to false.

Parameters:

statement - the statement (BeliefCtx or FactCtx) to be added

Throws:

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

removeCausingStatement

public void removeCausingStatement(StatementCtx statement)
                            throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Removes the specified statement (belief or fact) as a statement causing a precondition to evaluate to false.

Parameters:

statement - the statement to be removed

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if statement is null, no statements are present, or the statements is not found

getCausingStatements

public java.util.Enumeration getCausingStatements()
                                           throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Returns a list of all the statements (facts or beliefs) causing a precondition to evaluate to false.

Returns:

Enumeration an enumeration of BeliefCtx or FactCtx

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if there are no statements

setCausingDetectable

public void setCausingDetectable(DetectableCtx detectable)
                          throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Sets the detectable causing the unavailability of the frame.

Parameters:

detectable - the DetectableCtx for the detectable causing the unavailability

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if no detectable is specified.

getCausingDetectable

public DetectableCtx getCausingDetectable()
                                   throws gov.nasa.arc.brahms.common.exceptions.BrahmsException

Returns the detectable causing the unavailability of the frame.

Returns:

DetectableCtx the context for the detectable causing the unavailability

Throws:

gov.nasa.arc.brahms.common.exceptions.BrahmsException - if no detectable is specified.