Package soot.jbco.jimpleTransformations

Class MethodRenamer

java.lang.Object

soot.Transformer

soot.SceneTransformer

soot.jbco.jimpleTransformations.MethodRenamer

All Implemented Interfaces:

IJbcoTransform

public class MethodRenamer
extends SceneTransformer
implements IJbcoTransform

Creates new method names using names of fields or generates randomly. New names are unique through the whole application.

Some methods cannot be renamed:

• main methods
• constructors
• static initializers

(these methods are filtered by names)

• ones that override/implement library methods

To find methods from last group the next approach is used. All superclasses and interfaces that processing class extends / implements are collected. The children of that items are taken and united together along with processing class. The same action is performed for every item of the obtained result until the full "tree" is not created. Then from this tree, the classes that do not have methods with similar to searching signature, are removed. The left items that have SootClass.isLibraryClass() true are searching ones.

This complex approach is used to detect indirect inheritance. Consider next example:

                            ,--------.
                            |A       |
                            |--------|
                            |--------|
                            |method()|
                            `--------'
                              /    \
                             /      \
 ,-----------------------------.  ,--------.       ,--------. ,--------------------------------.
 |D                            |  |B       |       |E       | | Note: E is a library interface |
 |-----------------------------|  |--------|       |--------| `--------------------------------'
 |-----------------------------|  |--------|       |--------|
 |method()                     |  |method()|       |method()|
 |method(java.lang.String, int)|  `--------'       `--------'
 `-----------------------------'           \      /
                                  ,------------------------.
                                  |C                       |
                                  |------------------------|
                                  |------------------------|
                                  |method()                |
                                  |method(java.lang.String)|
                                  |method(long, int)       |
                                  `------------------------'
 

Thus when D#method() is processed, it must not be renamed as there is class C that implements library one (E#method()).

After applying this transformer the next result is expected:

• #method() is not renamed in any application classes as it overrides one from library
• #method(java.lang.String), #method(long, int) and #method(java.lang.String, int) are renamed and have the same name. Such renaming behaviour allows having renaming map for every class with old method name as a key and new method name as a value

Since:

24-Jan-2006

Author:

Michael Batchelder, Pavel Nesterovich

Field Summary

Fields

Modifier and Type	Field	Description
static String	name

Fields inherited from interface soot.jbco.IJbcoTransform

debug, out, output

Constructor Summary

Constructors

Constructor	Description
MethodRenamer(Singletons.Global global)	Singleton constructor.

Method Summary

Modifier and Type	Method	Description
String[]	getDependencies()	Gets array of jbco transformer code names on which current transformer depends on.
String	getName()	Gets the code name of jbco transformer implementation.
String	getNewName()	Creates new unique method name.
Map<String,String>	getRenamingMap(String className)	Gets renaming map for specific class.
protected void	internalTransform(String phaseName, Map<String,String> options)	Performs the transformation on the Scene, under the given phaseName and with the given Options.
void	outputSummary()	Prints summary of the produced changes.
static MethodRenamer	v()	Singleton getter.

Methods inherited from class soot.SceneTransformer

transform, transform, transform

Methods inherited from class java.lang.Object

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

Methods inherited from interface soot.jbco.IJbcoTransform

isDebugEnabled, isVerbose

Field Detail

name

public static final String name

See Also:

Constant Field Values

Constructor Detail

MethodRenamer

public MethodRenamer(Singletons.Global global)

Singleton constructor.

Parameters:

global - the singletons container. Must not be null

Throws:

NullPointerException - when global argument is null

Method Detail

v

public static MethodRenamer v()

Singleton getter.

Returns:

returns instance of MethodRenamer

getName

public String getName()

Description copied from interface: IJbcoTransform

Gets the code name of jbco transformer implementation.

Specified by:

getName in interface IJbcoTransform

Returns:

the code name of jbco transformer

getDependencies

public String[] getDependencies()

Description copied from interface: IJbcoTransform

Gets array of jbco transformer code names on which current transformer depends on.

Specified by:

getDependencies in interface IJbcoTransform

Returns:

array of code names

outputSummary

public void outputSummary()

Description copied from interface: IJbcoTransform

Prints summary of the produced changes.

Specified by:

outputSummary in interface IJbcoTransform

getRenamingMap

public Map<String,String> getRenamingMap(String className)

Gets renaming map for specific class.

Parameters:

className - the name of class to get renaming map for

Returns:

the map where the key is old method name, the value - new method name. Never null

internalTransform

protected void internalTransform(String phaseName,
                                 Map<String,String> options)

Description copied from class: SceneTransformer

Performs the transformation on the Scene, under the given phaseName and with the given Options.

Specified by:

internalTransform in class SceneTransformer

getNewName

public String getNewName()

Creates new unique method name.

Returns:

newly generated junk name that DOES NOT exist yet