Package net.ssehub.easy.reasoning.sseReasoner.model

Class SubstitutionVisitor

java.lang.Object

net.ssehub.easy.varModel.cst.BasicCopyVisitor

net.ssehub.easy.reasoning.sseReasoner.model.SubstitutionVisitor

All Implemented Interfaces:

IConstraintTreeVisitor

public class SubstitutionVisitor
extends BasicCopyVisitor

Substitutes variables in a constraint syntax tree by copying the syntax tree. May be reused after calling clear(). #addVariableMapping(AbstractVariable, Variable) takes precedence over #setMappings(Map).

Author:

Sizonenko, Holger Eichelberger

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	containsSelf
private ConstraintSyntaxTree	excludeFromMapping
private ContextStack	globalMapping
private java.util.Map<AbstractVariable,ConstraintSyntaxTree>	mapping
private AbstractVariable	self
private ConstraintSyntaxTree	selfEx

Constructor Summary

Constructors

Constructor	Description
SubstitutionVisitor()	Creates a copy visitor without mapping.
SubstitutionVisitor(ContextStack globalMapping)	Creates a copy visitor with explicit mapping.

Method Summary

Modifier and Type	Method	Description
ConstraintSyntaxTree	accept(ConstraintSyntaxTree cst)	Accepts this on cst and returns BasicCopyVisitor.getResult().
ConstraintSyntaxTree	acceptAndClear(ConstraintSyntaxTree cst)	Accepts this on cst, returns BasicCopyVisitor.getResult() and clears this.
SubstitutionVisitor	addVariableMapping(AbstractVariable orig, ConstraintSyntaxTree ex)	Adds a variable mapping to be considered during substitution.
SubstitutionVisitor	addVariableMapping(AbstractVariable orig, AbstractVariable dest, int derefCount)	Adds a variable mapping to be considered during substitution.
void	clear()	Clears this visitor for reuse.
SubstitutionVisitor	clearVariableMapping()	Clears the entire variable mapping.
SubstitutionVisitor	clearVariableMapping(AbstractVariable var)	Clears the mapping for a given variable.
boolean	containsSelf()	Returns whether the last execution visited a self.
void	excludeFromMapping(ConstraintSyntaxTree cst)	Excludes the given expression from mapping, e.g., if the expression is an already complete accessor expression and a mapping would be based on a previously registered (incorrect) mapping.
private ConstraintSyntaxTree	map(Variable variable)	Maps a variable to its accessor expression.
void	setMappings(ContextStack globalMapping)	Sets the mapping.
SubstitutionVisitor	setSelf(ConstraintSyntaxTree selfEx)	Defines self in terms of an expression.
SubstitutionVisitor	setSelf(AbstractVariable self)	Defines self in terms of a variable declaration.
void	visitAnnotationVariable(AttributeVariable variable)	Visits a AttributeVariable.
void	visitComment(Comment comment)	Visits a comment.
void	visitCompoundAccess(CompoundAccess access)	Visits a compound access node.
void	visitDeferInitExpression(DeferInitExpression expression)	Visits a default init expression.
void	visitSelf(Self self)	Visits self.
void	visitVariable(Variable variable)	Visits a variable.

Methods inherited from class net.ssehub.easy.varModel.cst.BasicCopyVisitor

getCopyExpressions, getCopyVariables, getLogger, getResult, inferDatatype, mapVariable, mapVariable, setCopyConstants, setCopyExpressions, setCopyVariables, setDoInferDatatype, setResult, visitBlockExpression, visitCompoundInitializer, visitConstantValue, visitContainerInitializer, visitContainerOperationCall, visitIfThen, visitLet, visitMultiAndExpression, visitOclFeatureCall, visitParenthesis, visitUnresolvedExpression

Methods inherited from class java.lang.Object

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

Field Detail

mapping

private java.util.Map<AbstractVariable,ConstraintSyntaxTree> mapping

globalMapping

private ContextStack globalMapping

selfEx

private ConstraintSyntaxTree selfEx

self

private AbstractVariable self

containsSelf

private boolean containsSelf

excludeFromMapping

private ConstraintSyntaxTree excludeFromMapping

Constructor Detail

SubstitutionVisitor

public SubstitutionVisitor()

Creates a copy visitor without mapping.

SubstitutionVisitor

public SubstitutionVisitor(ContextStack globalMapping)

Creates a copy visitor with explicit mapping.

Parameters:

globalMapping - a mapping from variable declarations to new access expressions, existing variable declarations are taken over if no mapping is given, may be null in case of no mapping at all

See Also:

setMappings(ContextStack)

Method Detail

setMappings

public void setMappings(ContextStack globalMapping)

Sets the mapping. [init, reuse]

Parameters:

globalMapping - a mapping from variable declarations to new access expressions, existing variable declarations are taken over if no mapping is given, may be null in case of no mapping at all

containsSelf

public boolean containsSelf()

Returns whether the last execution visited a self.

Returns:

true for self, false else

clear

public void clear()

Clears this visitor for reuse.

Overrides:

clear in class BasicCopyVisitor

See Also:

clearVariableMapping()

addVariableMapping

public SubstitutionVisitor addVariableMapping(AbstractVariable orig,
                                              AbstractVariable dest,
                                              int derefCount)

Adds a variable mapping to be considered during substitution. Takes precedence over #setMappings(Map). If a variable mapping is defined by #setMappings(Map), potential transitive mappings of dest are considered and instead of orig-dest, a mapping from orig to the transitive value is registered.

Parameters:

orig - the original variable to be replaced (may be null, ignored)

dest - the destination variable to replace orig (may be null, ignored)

derefCount - the number of refBy operations to apply to the expression refering to dest

Returns:

this

addVariableMapping

public SubstitutionVisitor addVariableMapping(AbstractVariable orig,
                                              ConstraintSyntaxTree ex)

Adds a variable mapping to be considered during substitution. Takes precedence over #setMappings(Map).

Parameters:

orig - the original variable to be replaced (may be null, ignored)

ex - the expression to replace orig

Returns:

this

clearVariableMapping

public SubstitutionVisitor clearVariableMapping(AbstractVariable var)

Clears the mapping for a given variable.

Parameters:

var - the variable to clear the mapping for (may be null, ignored)

Returns:

this

clearVariableMapping

public SubstitutionVisitor clearVariableMapping()

Clears the entire variable mapping.

Returns:

this

setSelf

public SubstitutionVisitor setSelf(ConstraintSyntaxTree selfEx)

Defines self in terms of an expression.

Parameters:

selfEx - the expression (may be null, ignored then).

Returns:

this

setSelf

public SubstitutionVisitor setSelf(AbstractVariable self)

Defines self in terms of a variable declaration. Creates a variable on demand and re-uses it. Dont' call also setSelf(ConstraintSyntaxTree) on the same expression.

Parameters:

self - the variable (declaration) representing self (may be null, ignored then).

Returns:

this

accept

public ConstraintSyntaxTree accept(ConstraintSyntaxTree cst)

Accepts this on cst and returns BasicCopyVisitor.getResult().

Parameters:

cst - the constraint to visit

Returns:

the visiting result

acceptAndClear

public ConstraintSyntaxTree acceptAndClear(ConstraintSyntaxTree cst)

Accepts this on cst, returns BasicCopyVisitor.getResult() and clears this.

Parameters:

cst - the constraint to visit

Returns:

the visiting result

visitAnnotationVariable

public void visitAnnotationVariable(AttributeVariable variable)

Description copied from interface: IConstraintTreeVisitor

Visits a AttributeVariable.

Specified by:

visitAnnotationVariable in interface IConstraintTreeVisitor

Overrides:

visitAnnotationVariable in class BasicCopyVisitor

Parameters:

variable - the attribute variable which should be visited

visitVariable

public void visitVariable(Variable variable)

Description copied from interface: IConstraintTreeVisitor

Visits a variable.

Specified by:

visitVariable in interface IConstraintTreeVisitor

Overrides:

visitVariable in class BasicCopyVisitor

Parameters:

variable - the variable which should be visited

map

private ConstraintSyntaxTree map(Variable variable)

Maps a variable to its accessor expression.

Parameters:

variable - the variable to map

Returns:

the accessor expression, may be null

excludeFromMapping

public void excludeFromMapping(ConstraintSyntaxTree cst)

Excludes the given expression from mapping, e.g., if the expression is an already complete accessor expression and a mapping would be based on a previously registered (incorrect) mapping. Comparison is done by reference.

Parameters:

cst - the expression to exclude, may be null for no exclude

visitCompoundAccess

public void visitCompoundAccess(CompoundAccess access)

Description copied from interface: IConstraintTreeVisitor

Visits a compound access node.

Specified by:

visitCompoundAccess in interface IConstraintTreeVisitor

Overrides:

visitCompoundAccess in class BasicCopyVisitor

Parameters:

access - the compound access node

visitComment

public void visitComment(Comment comment)

Description copied from interface: IConstraintTreeVisitor

Visits a comment.

Specified by:

visitComment in interface IConstraintTreeVisitor

Overrides:

visitComment in class BasicCopyVisitor

Parameters:

comment - the comment node which should be visited

visitSelf

public void visitSelf(Self self)

Description copied from interface: IConstraintTreeVisitor

Visits self.

Specified by:

visitSelf in interface IConstraintTreeVisitor

Overrides:

visitSelf in class BasicCopyVisitor

Parameters:

self - the self object to visit

visitDeferInitExpression

public void visitDeferInitExpression(DeferInitExpression expression)

Visits a default init expression.

Specified by:

visitDeferInitExpression in interface IConstraintTreeVisitor

Overrides:

visitDeferInitExpression in class BasicCopyVisitor

Parameters:

expression - the expression