de.uka.ilkd.key.rule.metaconstruct

Class EnhancedForElimination

java.lang.Object

de.uka.ilkd.key.java.JavaSourceElement

de.uka.ilkd.key.java.JavaProgramElement

de.uka.ilkd.key.java.JavaNonTerminalProgramElement

de.uka.ilkd.key.rule.metaconstruct.ProgramTransformer

de.uka.ilkd.key.rule.metaconstruct.EnhancedForElimination

All Implemented Interfaces:

Expression, ExpressionContainer, ModelElement, NamedModelElement, NamedProgramElement, NonTerminalProgramElement, ProgramElement, Reference, MemberReference, NameReference, PackageReferenceContainer, ReferencePrefix, ReferenceSuffix, TypeReference, TypeReferenceContainer, TypeReferenceInfix, SourceElement, Statement, StatementContainer, SVSubstitute

public class EnhancedForElimination
extends ProgramTransformer

This class defines a meta operator to resolve an enhanced for loop - by transformation to a "normal" loop. This class is used to transform an enh. for loop over an iterable object into a while loop + surrounding statements.

Author:

mulbrich, bruns

Field Summary

Fields

Modifier and Type	Field and Description
private static String	ARR
private static String	HAS_NEXT
private static String	IT
private static String	ITERABLE_CLASS_NAME
private static String	ITERATOR
private static String	ITERATOR_METH
private static String	NEXT
private static String	VALUES

Constructor Summary

Constructors

Constructor and Description
EnhancedForElimination(EnhancedFor forStatement)

Method Summary

Modifier and Type	Method and Description
private boolean	isIterable(Expression expression, Services services) Checks if an expression is an Iterable.
private ProgramElement	makeArrayForLoop(EnhancedFor enhancedFor, Services services)
private StatementBlock	makeBlock(ProgramVariable itVar, ProgramVariable valuesVar, LocalVariableDeclaration lvd, Statement body)
private ProgramElement	makeIterableForLoop(EnhancedFor enhancedFor, Services services)
private Statement	makeValuesUpdate(ProgramVariable valuesVar, LocalVariableDeclaration lvd)
private void	setInvariant(EnhancedFor original, LoopStatement transformed, Services services) Transfer the invariant from original enhanced loop to the transformed while or for loop.
ProgramElement	transform(ProgramElement pe, Services services, SVInstantiations svInst) An enhanced for loop is executed by transforming it into a "normal" for loop.

Methods inherited from class de.uka.ilkd.key.rule.metaconstruct.ProgramTransformer

body, getChildAt, getChildCount, getDimensions, getExpressionAt, getExpressionCount, getKeYJavaType, getKeYJavaType, getKeYJavaType, getLastElement, getName, getPackageReference, getProgramElementName, getReferencePrefix, getStatementAt, getStatementCount, getTypeReferenceAt, getTypeReferenceCount, name, neededInstantiations, needs, prettyPrint, setReferencePrefix, toString, visit

Methods inherited from class de.uka.ilkd.key.java.JavaNonTerminalProgramElement

compatibleBlockSize, equals, equalsModRenaming, getArrayPos, hashCode, match, matchChildren

Methods inherited from class de.uka.ilkd.key.java.JavaProgramElement

getComments, prettyPrintMain, reuseSignature

Methods inherited from class de.uka.ilkd.key.java.JavaSourceElement

getEndPosition, getFirstElement, getFirstElementIncludingBlocks, getParentClass, getPositionInfo, getRelativePosition, getStartPosition, setParentClass, toSource, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface de.uka.ilkd.key.java.ProgramElement

getComments, match

Field Detail

IT

private static final String IT

See Also:

Constant Field Values

ARR

private static final String ARR

See Also:

Constant Field Values

VALUES

private static final String VALUES

See Also:

Constant Field Values

ITERABLE_CLASS_NAME

private static final String ITERABLE_CLASS_NAME

See Also:

Constant Field Values

ITERATOR_METH

private static final String ITERATOR_METH

See Also:

Constant Field Values

HAS_NEXT

private static final String HAS_NEXT

See Also:

Constant Field Values

NEXT

private static final String NEXT

See Also:

Constant Field Values

ITERATOR

private static final String ITERATOR

See Also:

Constant Field Values

Constructor Detail

EnhancedForElimination

public EnhancedForElimination(EnhancedFor forStatement)

Method Detail

transform

public ProgramElement transform(ProgramElement pe,
                                Services services,
                                SVInstantiations svInst)

An enhanced for loop is executed by transforming it into a "normal" for loop. For an enhanced for "for(type var : exp) stm" the fields of LoopStatement are used as follows:

• inits: type var
• guard: exp
• updates remains empty
• body: stm

Loops over arrays are treated by a taclet without use of this class.

Loops over Iterable-objects are treated by this meta-construct.

The rules which use this meta construct must ensure that exp is of type Iterable.

Specified by:

transform in class ProgramTransformer

Parameters:

pe - the ProgramElement on which the execution is performed

services - the Services with all necessary information about the java programs

svInst - the instantiations of the schemavariables

Returns:

the transformated program

See Also:

#makeIterableForLoop(LocalVariableDeclaration, Expression, Statement), ProgramTransformer.transform(de.uka.ilkd.key.java.ProgramElement, de.uka.ilkd.key.java.Services, de.uka.ilkd.key.rule.inst.SVInstantiations)

isIterable

private boolean isIterable(Expression expression,
                           Services services)

Checks if an expression is an Iterable.

Parameters:

expression - the expression to check

services - the services for lookups

Returns:

true, if expression's type is a subtype of Iterable

makeArrayForLoop

private ProgramElement makeArrayForLoop(EnhancedFor enhancedFor,
                                        Services services)

makeIterableForLoop

private ProgramElement makeIterableForLoop(EnhancedFor enhancedFor,
                                           Services services)

makeBlock

private StatementBlock makeBlock(ProgramVariable itVar,
                                 ProgramVariable valuesVar,
                                 LocalVariableDeclaration lvd,
                                 Statement body)

makeValuesUpdate

private Statement makeValuesUpdate(ProgramVariable valuesVar,
                                   LocalVariableDeclaration lvd)

setInvariant

private void setInvariant(EnhancedFor original,
                          LoopStatement transformed,
                          Services services)

Transfer the invariant from original enhanced loop to the transformed while or for loop.

Parameters:

services -