org.eclipse.ocl
Class AbstractEvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

java.lang.Object
  org.eclipse.ocl.utilities.AbstractVisitor<java.lang.Object,C,O,P,EL,PM,S,COA,SSA,CT>
      org.eclipse.ocl.AbstractEvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

All Implemented Interfaces:

EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>, Visitor<java.lang.Object,C,O,P,EL,PM,S,COA,SSA,CT>

Direct Known Subclasses:

EvaluationVisitorImpl

public abstract class AbstractEvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>
extends AbstractVisitor<java.lang.Object,C,O,P,EL,PM,S,COA,SSA,CT>
implements EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

An evaluation visitor implementation for OCL expressions.

Note that this class is not intended to be used or extended by clients. Use the AbstractEvaluationVisitor interface, instead.

See the Environment class for a description of the generic type parameters of this class.

Field Summary

Fields inherited from class org.eclipse.ocl.utilities.AbstractVisitor

result

Constructor Summary

protected

AbstractEvaluationVisitor(Environment<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E> env, EvaluationEnvironment<C,O,P,CLS,E> evalEnv, java.util.Map<? extends CLS,? extends java.util.Set<? extends E>> extentMap) Initializes me.

Method Summary

protected java.lang.Object	call(O operation, OCLExpression<C> body, java.lang.Object target, java.lang.Object[] args) Invokes the specified additional operation on a target object.
protected java.lang.Number	coerceNumber(java.lang.Number number) Tests whether a given number can be safely coerced to Double or Integer without changing the value of the number.
protected C	getBoolean() Obtains my environment's implementation of the OCL Boolean type.
Environment<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>	getEnvironment() Obtains the environment that provides the metamodel semantics for the expression to be evaluated.
EvaluationEnvironment<C,O,P,CLS,E>	getEvaluationEnvironment() Obtains the evaluation environment that keeps track of variable values and knows how to call operations, navigate properties, etc.
java.util.Map<? extends CLS,? extends java.util.Set<? extends E>>	getExtentMap() Obtains the mapping of model classes to their extends.
protected C	getInteger() Obtains my environment's implementation of the OCL Integer type.
protected java.lang.Object	getInvalid() Obtains my environment's implementation of the OclInvalid value.
protected java.lang.String	getName(java.lang.Object namedElement) Obtains the name of the specified element, if it has one.
protected OCLExpression<C>	getOperationBody(O operation) Obtains the body of the specified operation's def or body expression, if any.
protected OCLExpression<C>	getPropertyBody(P property) Obtains the body of the specified property's def or der expression, if any.
protected C	getReal() Obtains my environment's implementation of the OCL Real type.
protected ExpressionInOCL<C,PM>	getSpecification(CT constraint) Overridden by subclasses interested in visiting constraints, to get the constraint's specification.
protected OCLStandardLibrary<C>	getStandardLibrary() Obtains my environment's OCL Standard Library implementation.
protected C	getString() Obtains my environment's implementation of the OCL String type.
protected UMLReflection<PK,C,O,P,EL,PM,S,COA,SSA,CT>	getUMLReflection()
protected C	getUnlimitedNatural() Obtains my environment's implementation of the OCL UnlimitedNatural type.
protected EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>	getVisitor() Obtains the visitor on which I perform nested Visitable.accept(org.eclipse.ocl.utilities.Visitor) calls.
protected java.lang.Number	higherPrecisionNumber(java.lang.Number number) Coerces the given number to Double or Long precision, if possible.
protected boolean	isLaxNullHandling() Queries whether our evaluation environment has the option for lax null handling enabled.
protected boolean	isUndefined(java.lang.Object value) Convenience method to determine whether the specified value is the null or OclInvalid.
protected java.lang.Object	navigate(P property, OCLExpression<C> derivation, java.lang.Object target) Obtains an object's value of the specified additional property.
protected java.lang.Boolean	oclIsKindOf(java.lang.Object value, java.lang.Object typeArg) Checks whether the supplied value is an instance of the supplied type or one of its super types.
protected java.lang.Boolean	oclIsTypeOf(java.lang.Object value, java.lang.Object typeArg) Checks whether the supplied object is an instance of the supplied type.
protected void	setEvaluationEnvironment(EvaluationEnvironment<C,O,P,CLS,E> evaluationEnvironment) Sets the evaluation environment to be used by this visitor during evaluation.
java.lang.String	toString()
java.lang.Object	visitConstraint(CT constraint) This default implementation asserts that the constraint is boolean-valued if it is an invariant, pre-condition, or post-condition constraint and returns the value of its body expression by delegation to visitExpression(OCLExpression).
java.lang.Object	visitExpression(OCLExpression<C> expression) This default implementation simply asks the expression to accept me.

Methods inherited from class org.eclipse.ocl.utilities.AbstractVisitor

handleAssociationClassCallExp, handleCollectionItem, handleCollectionLiteralExp, handleCollectionRange, handleConstraint, handleExpressionInOCL, handleIfExp, handleIterateExp, handleIteratorExp, handleLetExp, handleMessageExp, handleOperationCallExp, handlePropertyCallExp, handleTupleLiteralExp, handleTupleLiteralPart, handleVariable, safeVisit, visitAssociationClassCallExp, visitBooleanLiteralExp, visitCollectionItem, visitCollectionLiteralExp, visitCollectionRange, visitEnumLiteralExp, visitExpressionInOCL, visitIfExp, visitIntegerLiteralExp, visitInvalidLiteralExp, visitIterateExp, visitIteratorExp, visitLetExp, visitMessageExp, visitNullLiteralExp, visitOperationCallExp, visitPropertyCallExp, visitRealLiteralExp, visitStateExp, visitStringLiteralExp, visitTupleLiteralExp, visitTupleLiteralPart, visitTypeExp, visitUnlimitedNaturalLiteralExp, visitUnspecifiedValueExp, visitVariable, visitVariableExp

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.ocl.utilities.Visitor

visitAssociationClassCallExp, visitBooleanLiteralExp, visitCollectionItem, visitCollectionLiteralExp, visitCollectionRange, visitEnumLiteralExp, visitExpressionInOCL, visitIfExp, visitIntegerLiteralExp, visitInvalidLiteralExp, visitIterateExp, visitIteratorExp, visitLetExp, visitMessageExp, visitNullLiteralExp, visitOperationCallExp, visitPropertyCallExp, visitRealLiteralExp, visitStateExp, visitStringLiteralExp, visitTupleLiteralExp, visitTupleLiteralPart, visitTypeExp, visitUnlimitedNaturalLiteralExp, visitUnspecifiedValueExp, visitVariable, visitVariableExp

Constructor Detail

AbstractEvaluationVisitor

protected AbstractEvaluationVisitor(Environment<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E> env,
                                    EvaluationEnvironment<C,O,P,CLS,E> evalEnv,
                                    java.util.Map<? extends CLS,? extends java.util.Set<? extends E>> extentMap)

Initializes me.

Parameters:

env - the current environment

evalEnv - an evaluation environment (map of variable names to values)

extentMap - a map of classes to their instance sets

Method Detail

getVisitor

protected final EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E> getVisitor()

Obtains the visitor on which I perform nested Visitable.accept(org.eclipse.ocl.utilities.Visitor) calls. This handles the case in which I am decorated by another visitor that must intercept every visitXxx() method. If I internally just recursively visit myself, then this decorator is cut out of the picture.

Returns:

my delegate visitor, which may be my own self or some other

setEvaluationEnvironment

protected void setEvaluationEnvironment(EvaluationEnvironment<C,O,P,CLS,E> evaluationEnvironment)

Sets the evaluation environment to be used by this visitor during evaluation.

Parameters:

evaluationEnvironment - non-null evaluation environment

Throws:

java.lang.IllegalArgumentException - if the passed evaluationEnvironment is null

Since:

1.3

getEvaluationEnvironment

public EvaluationEnvironment<C,O,P,CLS,E> getEvaluationEnvironment()

Description copied from interface: EvaluationVisitor

Obtains the evaluation environment that keeps track of variable values and knows how to call operations, navigate properties, etc.

Specified by:

getEvaluationEnvironment in interface EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

Returns:

the evaluation environment

getEnvironment

public Environment<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E> getEnvironment()

Description copied from interface: EvaluationVisitor

Obtains the environment that provides the metamodel semantics for the expression to be evaluated.

Specified by:

getEnvironment in interface EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

Returns:

the environment

getUMLReflection

protected UMLReflection<PK,C,O,P,EL,PM,S,COA,SSA,CT> getUMLReflection()

getExtentMap

public java.util.Map<? extends CLS,? extends java.util.Set<? extends E>> getExtentMap()

Description copied from interface: EvaluationVisitor

Obtains the mapping of model classes to their extends.

Specified by:

getExtentMap in interface EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

Returns:

the extent map

getStandardLibrary

protected OCLStandardLibrary<C> getStandardLibrary()

Obtains my environment's OCL Standard Library implementation.

Returns:

the OCL standard library

getInvalid

protected final java.lang.Object getInvalid()

Obtains my environment's implementation of the OclInvalid value.

Returns:

the invalid result

Since:

3.0

getBoolean

protected final C getBoolean()

Obtains my environment's implementation of the OCL Boolean type.

Returns:

the boolean type

getString

protected final C getString()

Obtains my environment's implementation of the OCL String type.

Returns:

the string type

getInteger

protected final C getInteger()

Obtains my environment's implementation of the OCL Integer type.

Returns:

the integer type

getUnlimitedNatural

protected final C getUnlimitedNatural()

Obtains my environment's implementation of the OCL UnlimitedNatural type.

Returns:

the unlimited natural type

getReal

protected final C getReal()

Obtains my environment's implementation of the OCL Real type.

Returns:

the real type

getName

protected java.lang.String getName(java.lang.Object namedElement)

Obtains the name of the specified element, if it has one.

Parameters:

namedElement - a named element

Returns:

its name, or null if it has none

visitExpression

public java.lang.Object visitExpression(OCLExpression<C> expression)

This default implementation simply asks the expression to accept me.

Specified by:

visitExpression in interface EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

Parameters:

expression - an OCL expression to evaluate

Returns:

the result of the evaluation

visitConstraint

public java.lang.Object visitConstraint(CT constraint)

This default implementation asserts that the constraint is boolean-valued if it is an invariant, pre-condition, or post-condition constraint and returns the value of its body expression by delegation to visitExpression(OCLExpression).

Specified by:

visitConstraint in interface EvaluationVisitor<PK,C,O,P,EL,PM,S,COA,SSA,CT,CLS,E>

Specified by:

visitConstraint in interface Visitor<java.lang.Object,C,O,P,EL,PM,S,COA,SSA,CT>

Overrides:

visitConstraint in class AbstractVisitor<java.lang.Object,C,O,P,EL,PM,S,COA,SSA,CT>

Returns:

for boolean-valued constraints (invariant, precondition, postcondition) Boolean.TRUE if the constraint holds and Boolean.FALSE if it is violated (including evaluations that result in OclInvalid). For operation body conditions, the value of the operation result

See Also:

AbstractVisitor.getSpecification(Object)

getSpecification

protected ExpressionInOCL<C,PM> getSpecification(CT constraint)

Description copied from class: AbstractVisitor

Overridden by subclasses interested in visiting constraints, to get the constraint's specification.

Overrides:

getSpecification in class AbstractVisitor<java.lang.Object,C,O,P,EL,PM,S,COA,SSA,CT>

Parameters:

constraint - a constraint

Returns:

its specification

See Also:

AbstractVisitor.visitConstraint(Object)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

isUndefined

protected boolean isUndefined(java.lang.Object value)

Convenience method to determine whether the specified value is the null or OclInvalid.

Parameters:

value - a value

Returns:

whether it is undefined

call

protected java.lang.Object call(O operation,
                                OCLExpression<C> body,
                                java.lang.Object target,
                                java.lang.Object[] args)

Invokes the specified additional operation on a target object. The invocation is performed in a nested evaluation environment.

Parameters:

operation - the operation to invoke

body - the operation's body expression

target - the object on which to evaluate the operation body

args - the arguments to the operation call

getOperationBody

protected OCLExpression<C> getOperationBody(O operation)

Obtains the body of the specified operation's def or body expression, if any.

Parameters:

operation - an operation

Returns:

its value expression, if any

getPropertyBody

protected OCLExpression<C> getPropertyBody(P property)

Obtains the body of the specified property's def or der expression, if any.

Parameters:

property - a property

Returns:

its value expression, if any

navigate

protected java.lang.Object navigate(P property,
                                    OCLExpression<C> derivation,
                                    java.lang.Object target)

Obtains an object's value of the specified additional property.

Parameters:

property - the property to navigate

derivation - the expression that computes its value

target - the object in which context to evaluate the derivation

Returns:

the property's value

oclIsTypeOf

protected java.lang.Boolean oclIsTypeOf(java.lang.Object value,
                                        java.lang.Object typeArg)

Checks whether the supplied object is an instance of the supplied type.

Parameters:

value - the value to check

typeArg - the type to check

Returns:

true if the object is an instance of the type, false otherwise.

oclIsKindOf

protected java.lang.Boolean oclIsKindOf(java.lang.Object value,
                                        java.lang.Object typeArg)

Checks whether the supplied value is an instance of the supplied type or one of its super types.

Parameters:

value - the value to check

typeArg - the type to check

Returns:

true iff the value is of the type or one of its super types.

coerceNumber

protected java.lang.Number coerceNumber(java.lang.Number number)

Tests whether a given number can be safely coerced to Double or Integer without changing the value of the number. Safe means that coercing a number to Double or Integer and then coercing it back to the original type will result in the same value (no loss of precision). This is trivial for types, which have a smaller domain then Integer or Double, but for example a Long number may not be safely coerced to Integer.

If the coercion is safe, the number will be returned as either Double or Integer, as appropriate to the original precision. Otherwise the original number is returned.

Parameters:

number - a number to coerce to Integer or Double

Returns:

the coerced number, or the original number, if coercion was not safe

Since:

1.2

higherPrecisionNumber

protected java.lang.Number higherPrecisionNumber(java.lang.Number number)

Coerces the given number to Double or Long precision, if possible. Note that this is only impossible for BigDecimal or BigInteger values, respectively, that are out of range of their primitive counterparts.

Parameters:

number - a number to coerce to Long or Double

Returns:

the coerced number, or the original number, in case of overflow

Since:

1.2

isLaxNullHandling

protected boolean isLaxNullHandling()

Queries whether our evaluation environment has the option for lax null handling enabled.

Returns:

whether lax null handling is enabled

Since:

1.3