de.rwth.i2.attestor.semantics.jimpleSemantics.jimple.values

Class Field

java.lang.Object

de.rwth.i2.attestor.semantics.jimpleSemantics.jimple.values.Field

All Implemented Interfaces:

SettableValue, Value

public class Field
extends Object
implements SettableValue

fields model selectors of objects, e.g. curr.next or x.left.right or in general expr.field, where expr specifies the origin of the selector and field its name.
In jimple expr must be a local variable, i.e. x.left.right is not possible. It is however supported by this class.

Author:

Hannah Arndt

Constructor Summary

Constructors

Constructor and Description
Field(Type type, Value originValue, SelectorLabel selectorLabel)

Method Summary

Modifier and Type	Method and Description
ConcreteValue	evaluateOn(ProgramState programState) evaluates the expression defining the origin and gets the element referenced by the field starting at this origin element.
ViolationPoints	getPotentialViolationPoints()
Type	getType()
boolean	needsMaterialization(ProgramState programState)
void	setValue(ProgramState programState, ConcreteValue concreteTarget) Sets the value of the field in programState to concreteTarget.
String	toString() "origin.field"

Methods inherited from class java.lang.Object

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

Constructor Detail

Field

public Field(Type type,
             Value originValue,
             SelectorLabel selectorLabel)

Method Detail

getType

public Type getType()

Specified by:

getType in interface Value

evaluateOn

public ConcreteValue evaluateOn(ProgramState programState)
                         throws NullPointerDereferenceException

evaluates the expression defining the origin and gets the element referenced by the field starting at this origin element.

Specified by:

evaluateOn in interface Value

Returns:

undefined if the origin evaluates to undefined or if the corresponding selector is missing at the origin element. The correct element otherwise.

Throws:

NullPointerDereferenceException

setValue

public void setValue(ProgramState programState,
                     ConcreteValue concreteTarget)
              throws NullPointerDereferenceException

Sets the value of the field in programState to concreteTarget.
In this case the heap is not changed by the expression.
Also logs a warning if the type of concreteTarget does not match the expected type for the field.

Specified by:

setValue in interface SettableValue

Parameters:

programState - the heap on which the assignment is performed

concreteTarget - the value that is assigned to the heap

Throws:

NullPointerDereferenceException - if the evaluation of the originValue results in a null pointer dereference.

needsMaterialization

public boolean needsMaterialization(ProgramState programState)

Specified by:

needsMaterialization in interface Value

toString

public String toString()

"origin.field"

Overrides:

toString in class Object

getPotentialViolationPoints

public ViolationPoints getPotentialViolationPoints()

Specified by:

getPotentialViolationPoints in interface Value

Returns:

The (variable,selector) pairs that might require materialization before this expression can be evaluated.