Package de.fraunhofer.aisec.cpg.graph.statements.expressions

Class Expression

java.lang.Object

de.fraunhofer.aisec.cpg.graph.Node

de.fraunhofer.aisec.cpg.graph.statements.Statement

de.fraunhofer.aisec.cpg.graph.statements.expressions.Expression

All Implemented Interfaces:

DeclarationHolder, HasType, Persistable, IVisitable<Node>

Direct Known Subclasses:

ArrayCreationExpression, ArrayRangeExpression, ArraySubscriptionExpression, BinaryOperator, CallExpression, CastExpression, CompoundStatementExpression, ConditionalExpression, ConstructExpression, DeclaredReferenceExpression, DeleteExpression, DesignatedInitializerExpression, ExpressionList, InitializerListExpression, Literal, NewExpression, TypeIdExpression, UnaryOperator, UninitializedValue

public class Expression
extends Statement
implements HasType

Represents one expression. It is used as a base class for multiple different types of expressions. The only constraint is, that each expression has a type.

Note: In our graph, Expression is inherited from Statement. This is a constraint of the C++ language. In C++, it is valid to have an expression (for example a Literal) as part of a function body, even though the expression value is not used. Consider the following code: int main() { 1; }

This is not possible in Java, the aforementioned code example would prompt a compile error.

Nested Class Summary

Nested classes/interfaces inherited from interface de.fraunhofer.aisec.cpg.graph.HasType

HasType.TypeListener

Field Summary

Fields

Modifier and Type	Field	Description
protected Type	type	The type of the value after evaluation.

Fields inherited from class de.fraunhofer.aisec.cpg.graph.statements.Statement

locals

Fields inherited from class de.fraunhofer.aisec.cpg.graph.Node

annotations, code, comment, dummy, EMPTY_NAME, file, implicit, location, log, name, nextCFG, nextDFG, nextEOG, prevDFG, prevEOG, TO_STRING_STYLE, typedefs

Constructor Summary

Constructors

Constructor	Description
Expression()

Method Summary

Modifier and Type	Method	Description
boolean	equals(java.lang.Object o)
java.util.Set<Type>	getPossibleSubTypes()
Type	getPropagationType()
Type	getType()
java.util.Set<HasType.TypeListener>	getTypeListeners()
int	hashCode()
void	refreshType()
void	registerTypeListener(HasType.TypeListener listener)
void	resetTypes(Type type)	Used to set the type and clear the possible subtypes list for when a type is more precise than the current.
void	setPossibleSubTypes(java.util.Set<Type> possibleSubTypes, HasType root)	Set the node's possible subtypes.
void	setType(Type type, HasType root)	Set the node's type.
java.lang.String	toString()
void	unregisterTypeListener(HasType.TypeListener listener)
void	updatePossibleSubtypes(java.util.Set<Type> types)
void	updateType(Type type)	Sideeffect free type modification WARNING: This should only be used by the TypeSystem Pass

Methods inherited from class de.fraunhofer.aisec.cpg.graph.statements.Statement

addDeclaration, getLocals, getLocalsPropertyEdge, removeLocal, setLocals

Methods inherited from class de.fraunhofer.aisec.cpg.graph.Node

addAnnotations, addNextCFG, addNextCFG, addNextDFG, addNextEOG, addPrevDFG, addPrevEOG, addTypedef, clearNextEOG, disconnectFromGraph, getAnnotations, getArgumentIndex, getCode, getFile, getId, getLocation, getName, getNextCFG, getNextDFG, getNextEOG, getNextEOGProperties, getNextEOGPropertyEdge, getPrevDFG, getPrevEOG, getPrevEOGProperties, getTypedefs, isDummy, isImplicit, removeNextDFG, removePrevDFG, removePrevEOGEntries, removePrevEOGEntry, setArgumentIndex, setCode, setComment, setDummy, setFile, setImplicit, setLocation, setName, setNextDFG, setNextEOG, setPrevDFG, setPrevEOG, setPrevEOGProperties, setTypedefs

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.fraunhofer.aisec.cpg.graph.DeclarationHolder

addIfNotContains, addIfNotContains, addIfNotContains

Methods inherited from interface de.fraunhofer.aisec.cpg.graph.HasType

setPossibleSubTypes, setType

Methods inherited from interface de.fraunhofer.aisec.cpg.processing.IVisitable

accept

Field Detail

type

protected Type type

The type of the value after evaluation.

Constructor Detail

Expression

public Expression()

Method Detail

getType

public Type getType()

Specified by:

getType in interface HasType

getPropagationType

public Type getPropagationType()

Specified by:

getPropagationType in interface HasType

Returns:

The returned Type is always the same as getType() with the exception of ReferenceType since there is no case in which we want to propagate a reference when using typeChanged()

updateType

public void updateType(Type type)

Description copied from interface: HasType

Sideeffect free type modification WARNING: This should only be used by the TypeSystem Pass

Specified by:

updateType in interface HasType

Parameters:

type - new type

updatePossibleSubtypes

public void updatePossibleSubtypes(java.util.Set<Type> types)

Specified by:

updatePossibleSubtypes in interface HasType

setType

public void setType(Type type,
                    HasType root)

Description copied from interface: HasType

Set the node's type. This may start a chain of type listener notifications

Specified by:

setType in interface HasType

Parameters:

type - new type

root - The node that initiated the type change chain. When a node receives a type setting command where root == this, we know that we have a type listener circle and can abort. If root == null, the type change is seen as an externally triggered event and subsequent type listeners receive the current node as their root.

getPossibleSubTypes

public java.util.Set<Type> getPossibleSubTypes()

Specified by:

getPossibleSubTypes in interface HasType

setPossibleSubTypes

public void setPossibleSubTypes(java.util.Set<Type> possibleSubTypes,
                                HasType root)

Description copied from interface: HasType

Set the node's possible subtypes. Listener circle detection works the same way as with HasType.setType(Type, HasType)

Specified by:

setPossibleSubTypes in interface HasType

resetTypes

public void resetTypes(Type type)

Description copied from interface: HasType

Used to set the type and clear the possible subtypes list for when a type is more precise than the current.

Specified by:

resetTypes in interface HasType

Parameters:

type - the more precise type

registerTypeListener

public void registerTypeListener(HasType.TypeListener listener)

Specified by:

registerTypeListener in interface HasType

unregisterTypeListener

public void unregisterTypeListener(HasType.TypeListener listener)

Specified by:

unregisterTypeListener in interface HasType

getTypeListeners

public java.util.Set<HasType.TypeListener> getTypeListeners()

Specified by:

getTypeListeners in interface HasType

refreshType

public void refreshType()

Specified by:

refreshType in interface HasType

toString

public java.lang.String toString()

Overrides:

toString in class Node

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class Statement

hashCode

public int hashCode()

Overrides:

hashCode in class Statement