Package net.ssehub.easy.varModel.cstEvaluation

Class ConstantAccessor

java.lang.Object

net.ssehub.easy.varModel.cstEvaluation.EvaluationAccessor

net.ssehub.easy.varModel.cstEvaluation.ConstantAccessor

public class ConstantAccessor
extends EvaluationAccessor

Implements an accessor for constant values. [public for testing]

Author:

Holger Eichelberger

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	isConstant
static Pool<ConstantAccessor>	POOL
private Value	value

Constructor Summary

Constructors

Modifier	Constructor	Description
private	ConstantAccessor()	Creates an instance.

Method Summary

Modifier and Type	Method	Description
ConstantAccessor	bind(Value value, boolean isConstant, EvaluationContext context)	Binds the accessor to the given value and context.
void	clear()	Clears the accessor for reuse.
Value	getReferenceValue()	Returns the value of a reference to the accessed element.
Value	getValue()	Returns the value of the accessed element.
EvaluationAccessor	getValue(EvaluationAccessor accessor)	Returns a nested value based on the given accessor.
IDecisionVariable	getVariable()	Returns the underlying variable.
boolean	isAssignable()	Returns whether values can be assigned to this evaluator.
boolean	isConstant()	Returns whether this accessor represents a constant in the sense of the evaluation process, i.e., a value that is already evaluated to its very end and not linked to any decision variable.
void	release()	Releases this instance.
boolean	setValue(Value value, boolean asAssignment)	Defines a new value for the accessed element.
java.lang.String	toString()

Methods inherited from class net.ssehub.easy.varModel.cstEvaluation.EvaluationAccessor

addBoundContainerElement, addBoundContainerElement, bind, bindContainer, bindContainer, clearContainerElements, dereferenceIfNeeded, getBoundContainerElement, getBoundContainerElementCount, getContext, getDereferencedValue, isAssigned, release, setValue, validateContext

Methods inherited from class java.lang.Object

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

Field Detail

POOL

public static final Pool<ConstantAccessor> POOL

value

private Value value

isConstant

private boolean isConstant

Constructor Detail

ConstantAccessor

private ConstantAccessor()

Creates an instance. Private due to pooling.

Method Detail

bind

public ConstantAccessor bind(Value value,
                             boolean isConstant,
                             EvaluationContext context)

Binds the accessor to the given value and context.

Parameters:

value - the actual value

isConstant - whether value is still (potentially) linked by reference to a decision variable (false), else whether it is actually a truely constant

context - the evaluation context

Returns:

this (builder pattern)

clear

public void clear()

Description copied from class: EvaluationAccessor

Clears the accessor for reuse.

Overrides:

clear in class EvaluationAccessor

getValue

public Value getValue()

Description copied from class: EvaluationAccessor

Returns the value of the accessed element.

Specified by:

getValue in class EvaluationAccessor

Returns:

the value (may be null if undefined)

setValue

public boolean setValue(Value value,
                        boolean asAssignment)

Description copied from class: EvaluationAccessor

Defines a new value for the accessed element. In case of failures, add appropriate messages to the context.

Specified by:

setValue in class EvaluationAccessor

Parameters:

value - the new value

asAssignment - does this happen through an IVML assignment operation

Returns:

true if successful, false else

isAssignable

public boolean isAssignable()

Description copied from class: EvaluationAccessor

Returns whether values can be assigned to this evaluator.

Specified by:

isAssignable in class EvaluationAccessor

Returns:

true if values can be assigned, false else

release

public void release()

Description copied from class: EvaluationAccessor

Releases this instance.

Specified by:

release in class EvaluationAccessor

getVariable

public IDecisionVariable getVariable()

Description copied from class: EvaluationAccessor

Returns the underlying variable.

Specified by:

getVariable in class EvaluationAccessor

Returns:

the underlying variable (may be null)

getValue

public EvaluationAccessor getValue(EvaluationAccessor accessor)

Description copied from class: EvaluationAccessor

Returns a nested value based on the given accessor.

Overrides:

getValue in class EvaluationAccessor

Parameters:

accessor - the accessor to determine the nested value

Returns:

the nested value

getReferenceValue

public Value getReferenceValue()

Description copied from class: EvaluationAccessor

Returns the value of a reference to the accessed element.

Specified by:

getReferenceValue in class EvaluationAccessor

Returns:

the value (may be null if undefined)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

isConstant

public boolean isConstant()

Description copied from class: EvaluationAccessor

Returns whether this accessor represents a constant in the sense of the evaluation process, i.e., a value that is already evaluated to its very end and not linked to any decision variable.

Overrides:

isConstant in class EvaluationAccessor

Returns:

true for constant, false else