Class ClassHierarchy

java.lang.Object

com.ibm.wala.ipa.cha.ClassHierarchy

All Implemented Interfaces:

IClassHierarchy, Iterable<IClass>

public class ClassHierarchy
extends Object
implements IClassHierarchy

Simple implementation of a class hierarchy.

Note that this class hierarchy implementation is mutable. You can add classes via addClass(). You can add a class even if c.getClassLoader() does not appear in getLoaders().

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ClassHierarchy.MissingSuperClassHandling

Method Summary

Modifier and Type	Method	Description
boolean	addClass(IClass klass)
void	clearCaches()	Clear internal caches that may be invalidated by addition of new classes, e.g., a cache of the results of IClassHierarchy.getPossibleTargets(MethodReference).
Collection<IClass>	computeSubClasses(TypeReference type)	Return set of all subclasses of type in the Class Hierarchy TODO: Tune this implementation.
ClassLoaderFactory	getFactory()
Collection<IClass>	getImmediateSubclasses(IClass klass)
Set<IClass>	getImplementors(TypeReference type)	TODO: tune this if necessary
Collection<TypeReference>	getJavaLangErrorTypes()	Solely for optimization; return a Collection<TypeReference> representing the subclasses of Error
Collection<TypeReference>	getJavaLangRuntimeExceptionTypes()	Solely for optimization; return a Collection<TypeReference> representing the subclasses of RuntimeException
IClass	getLeastCommonSuperclass(IClass a, IClass b)
TypeReference	getLeastCommonSuperclass(TypeReference a, TypeReference b)
IClassLoader	getLoader(ClassLoaderReference loaderRef)
IClassLoader[]	getLoaders()
int	getNumber(IClass c)
int	getNumberOfClasses()
int	getNumberOfImmediateSubclasses(IClass klass)
Set<IMethod>	getPossibleTargets(IClass declaredClass, MethodReference ref)	Find the possible receivers of a call to a method reference
Set<IMethod>	getPossibleTargets(MethodReference ref)	Find the possible targets of a call to a method reference.
IClass	getRootClass()
AnalysisScope	getScope()
ClassHierarchy.MissingSuperClassHandling	getSuperClassHandling()
final Set<TypeReference>	getUnresolvedClasses()
boolean	implementsInterface(IClass c, IClass i)	Does c implement i?
boolean	isAssignableFrom(IClass c1, IClass c2)	Does an expression c1 x := c2 y typecheck?
boolean	isInterface(TypeReference type)
boolean	isRootClass(IClass c)
boolean	isSubclassOf(IClass c, IClass t)	Is c a subclass of T?
Iterator<IClass>	iterator()
IClass	lookupClass(TypeReference a)	Find a class in this class hierarchy.
IField	resolveField(IClass klass, FieldReference f)
IField	resolveField(FieldReference f)
IMethod	resolveMethod(IClass receiverClass, Selector selector)	Return the unique target of an invocation of method on an object of type receiverClass
IMethod	resolveMethod(MethodReference m)	Return the unique receiver of an invocation of method on an object of type m.getDeclaredClass().
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Details

clearCaches

public void clearCaches()

Description copied from interface: IClassHierarchy

Clear internal caches that may be invalidated by addition of new classes, e.g., a cache of the results of IClassHierarchy.getPossibleTargets(MethodReference).

Specified by:

clearCaches in interface IClassHierarchy

addClass

public boolean addClass(IClass klass)

Specified by:

addClass in interface IClassHierarchy

Returns:

true if the add succeeded; false if it failed for some reason

Throws:

IllegalArgumentException - if klass is null

getPossibleTargets

public Set<IMethod> getPossibleTargets(MethodReference ref)

Find the possible targets of a call to a method reference. Note that if the reference is to an instance initialization method, we assume the method was called with invokespecial rather than invokevirtual.

Specified by:

getPossibleTargets in interface IClassHierarchy

Parameters:

ref - method reference

Returns:

the set of IMethods that this call can resolve to.

Throws:

IllegalArgumentException - if ref is null

getPossibleTargets

public Set<IMethod> getPossibleTargets(IClass declaredClass,
 MethodReference ref)

Find the possible receivers of a call to a method reference

Specified by:

getPossibleTargets in interface IClassHierarchy

Parameters:

declaredClass - the class of the receiver

ref - method reference

Returns:

the set of IMethods that this call can resolve to.

resolveMethod

public IMethod resolveMethod(MethodReference m)

Description copied from interface: IClassHierarchy

Return the unique receiver of an invocation of method on an object of type m.getDeclaredClass(). Note that for Java, m.getDeclaredClass() must represent a class, not an interface. This method does not work for finding inherited methods in interfaces.

Specified by:

resolveMethod in interface IClassHierarchy

Returns:

IMethod, or null if no appropriate receiver is found.

resolveField

public IField resolveField(FieldReference f)

Specified by:

resolveField in interface IClassHierarchy

Returns:

the canonical IField that represents a given field , or null if none found

Throws:

IllegalArgumentException - if f is null

resolveField

public IField resolveField(IClass klass,
 FieldReference f)

Specified by:

resolveField in interface IClassHierarchy

Returns:

the canonical IField that represents a given field , or null if none found

Throws:

IllegalArgumentException - if f is null

IllegalArgumentException - if klass is null

resolveMethod

public IMethod resolveMethod(IClass receiverClass,
 Selector selector)

Description copied from interface: IClassHierarchy

Return the unique target of an invocation of method on an object of type receiverClass

Specified by:

resolveMethod in interface IClassHierarchy

Parameters:

receiverClass - type of receiver. Note that for Java, receiverClass must represent a class, not an interface. This method does not work for finding inherited methods in interfaces.

selector - method signature

Returns:

Method resolved method abstraction

toString

public String toString()

Overrides:

toString in class Object

getFactory

public ClassLoaderFactory getFactory()

Specified by:

getFactory in interface IClassHierarchy

getLeastCommonSuperclass

public IClass getLeastCommonSuperclass(IClass a,
 IClass b)

Specified by:

getLeastCommonSuperclass in interface IClassHierarchy

Throws:

IllegalArgumentException - if A is null

getLeastCommonSuperclass

public TypeReference getLeastCommonSuperclass(TypeReference a,
 TypeReference b)

Specified by:

getLeastCommonSuperclass in interface IClassHierarchy

lookupClass

public IClass lookupClass(TypeReference a)

Find a class in this class hierarchy.

Specified by:

lookupClass in interface IClassHierarchy

Returns:

the IClass for a if found; null if can't find the class.

Throws:

IllegalArgumentException - if A is null

isSubclassOf

public boolean isSubclassOf(IClass c,
 IClass t)

Is c a subclass of T?

Specified by:

isSubclassOf in interface IClassHierarchy

Throws:

IllegalArgumentException - if c is null

implementsInterface

public boolean implementsInterface(IClass c,
 IClass i)

Does c implement i?

Specified by:

implementsInterface in interface IClassHierarchy

Returns:

true iff i is an interface and c is a class that implements i, or c is an interface that extends i.

computeSubClasses

public Collection<IClass> computeSubClasses(TypeReference type)

Return set of all subclasses of type in the Class Hierarchy TODO: Tune this implementation. Consider caching if necessary.

Specified by:

computeSubClasses in interface IClassHierarchy

getJavaLangErrorTypes

public Collection<TypeReference> getJavaLangErrorTypes()

Solely for optimization; return a Collection<TypeReference> representing the subclasses of Error

kind of ugly. a better scheme?

Specified by:

getJavaLangErrorTypes in interface IClassHierarchy

getJavaLangRuntimeExceptionTypes

public Collection<TypeReference> getJavaLangRuntimeExceptionTypes()

Solely for optimization; return a Collection<TypeReference> representing the subclasses of RuntimeException

kind of ugly. a better scheme?

Specified by:

getJavaLangRuntimeExceptionTypes in interface IClassHierarchy

isInterface

public boolean isInterface(TypeReference type)

Specified by:

isInterface in interface IClassHierarchy

getImplementors

public Set<IClass> getImplementors(TypeReference type)

TODO: tune this if necessary

Specified by:

getImplementors in interface IClassHierarchy

Parameters:

type - an interface

Returns:

Set of IClass that represent implementors of the interface

iterator

public Iterator<IClass> iterator()

Specified by:

iterator in interface Iterable<IClass>

getNumberOfClasses

public int getNumberOfClasses()

Specified by:

getNumberOfClasses in interface IClassHierarchy

Returns:

The number of classes present in the class hierarchy.

getLoaders

public IClassLoader[] getLoaders()

Specified by:

getLoaders in interface IClassHierarchy

getLoader

public IClassLoader getLoader(ClassLoaderReference loaderRef)

Specified by:

getLoader in interface IClassHierarchy

getScope

public AnalysisScope getScope()

Specified by:

getScope in interface IClassHierarchy

getNumberOfImmediateSubclasses

public int getNumberOfImmediateSubclasses(IClass klass)

Specified by:

getNumberOfImmediateSubclasses in interface IClassHierarchy

Returns:

the number of classes that immediately extend klass. if klass is an array class A[][]...[], we return number of immediate subclasses of A. If A is primitive, we return 0.

getImmediateSubclasses

public Collection<IClass> getImmediateSubclasses(IClass klass)

Specified by:

getImmediateSubclasses in interface IClassHierarchy

Returns:

the classes that immediately extend klass. if klass is an array class A[][]...[], we return array classes B[][]...[] (same dimensionality) where B is an immediate subclass of A. If A is primitive, we return the empty set.

getRootClass

public IClass getRootClass()

Specified by:

getRootClass in interface IClassHierarchy

isRootClass

public boolean isRootClass(IClass c)
                    throws IllegalArgumentException

Specified by:

isRootClass in interface IClassHierarchy

Throws:

IllegalArgumentException

getNumber

public int getNumber(IClass c)

Specified by:

getNumber in interface IClassHierarchy

isAssignableFrom

public boolean isAssignableFrom(IClass c1,
 IClass c2)

Does an expression c1 x := c2 y typecheck?

i.e. is c2 a subtype of c1?

Specified by:

isAssignableFrom in interface IClassHierarchy

Throws:

IllegalArgumentException - if c1 is null

IllegalArgumentException - if c2 is null

getUnresolvedClasses

public final Set<TypeReference> getUnresolvedClasses()

Specified by:

getUnresolvedClasses in interface IClassHierarchy

getSuperClassHandling

public ClassHierarchy.MissingSuperClassHandling getSuperClassHandling()