proguard.classfile

Class MethodSignature

java.lang.Object

proguard.classfile.Signature

proguard.classfile.MethodSignature

All Implemented Interfaces:

java.lang.Comparable<Signature>, MethodInfo

public class MethodSignature
extends Signature
implements MethodInfo

Represents a Method signature containing a class, method and a descriptor.

In order to avoid a huge blow-up in memory consumption for analyses that rely heavily on method signatures, e.g. the creation of a call graph, this class provides the ability to cache signatures belonging to concrete Method objects. By using the corresponding computeIfAbsent(Clazz, Method) method, the amount of strings that need to be retained during runtime is reduced.

Field Summary

Fields

Modifier and Type	Field and Description
@Nullable MethodDescriptor	descriptor
@Nullable java.lang.String	method
static MethodSignature	UNKNOWN

Fields inherited from class proguard.classfile.Signature

className, fqn, hashCode, prettyFqn, referencedClass

Constructor Summary

Constructors

Constructor and Description
MethodSignature(@NotNull Clazz clazz)
MethodSignature(@NotNull Clazz clazz, @NotNull Method method)
MethodSignature(@Nullable java.lang.String className)
MethodSignature(@Nullable java.lang.String internalClassName, @Nullable java.lang.String method, @Nullable MethodDescriptor descriptor)
MethodSignature(@Nullable java.lang.String internalClassName, @Nullable java.lang.String method, @Nullable java.lang.String descriptor)

Method Summary

Modifier and Type	Method and Description
protected java.lang.String	calculateFqn()
protected java.lang.String	calculatePrettyFqn()
static void	clearCache() Remove all currently cached MethodSignature objects from the cache, allowing them to be removed by the garbage collector.
static MethodSignature	computeIfAbsent(Clazz clazz, Method method) Get the singleton MethodSignature object for this specific Method.
boolean	equals(java.lang.Object o)
@Nullable MethodDescriptor	getDescriptor() Returns the method's descriptor.
@Nullable java.lang.String	getMethodName() Returns the method's name.
Method	getReferencedMethod() Returns the Method reference that corresponds to the method represented by this MethodSignature or null if no reference is available (e.g.
boolean	isIncomplete() Check if this signature is missing information.
static boolean	matchesIgnoreNull(MethodSignature signature, MethodSignature wildcard) Fuzzy check if two MethodSignature objects are equal.
static boolean	matchesIgnoreNullAndDollar(MethodSignature signature, MethodSignature wildcard) Fuzzy check like .matchesIgnoreNull(MethodSignature) but allows dollar signs in type strings.

Methods inherited from class proguard.classfile.Signature

compareTo, computeIfAbsent, getClassName, getExternalPackageName, getFqn, getPackageName, getPrettyFqn, getReferencedClass, hashCode, of, setCacheEnabled, toString

Methods inherited from class java.lang.Object

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

Field Detail

UNKNOWN

public static final MethodSignature UNKNOWN

method

@Nullable
public final @Nullable java.lang.String method

descriptor

@Nullable
public final @Nullable MethodDescriptor descriptor

Constructor Detail

MethodSignature

public MethodSignature(@Nullable
                       @Nullable java.lang.String internalClassName,
                       @Nullable
                       @Nullable java.lang.String method,
                       @Nullable
                       @Nullable MethodDescriptor descriptor)

MethodSignature

public MethodSignature(@Nullable
                       @Nullable java.lang.String internalClassName,
                       @Nullable
                       @Nullable java.lang.String method,
                       @Nullable
                       @Nullable java.lang.String descriptor)

MethodSignature

public MethodSignature(@NotNull
                       @NotNull Clazz clazz,
                       @NotNull
                       @NotNull Method method)

MethodSignature

public MethodSignature(@NotNull
                       @NotNull Clazz clazz)

MethodSignature

public MethodSignature(@Nullable
                       @Nullable java.lang.String className)

Method Detail

getReferencedMethod

public Method getReferencedMethod()

Returns the Method reference that corresponds to the method represented by this MethodSignature or null if no reference is available (e.g. the methhod or its class were missing).

computeIfAbsent

public static MethodSignature computeIfAbsent(Clazz clazz,
                                              Method method)

Get the singleton MethodSignature object for this specific Method. If it is not yet available in the cache, it will be newly instantiated.

Parameters:

clazz - The class containing the target method

method - The method whose signature is to be generated

Returns:

The cached or newly generated MethodSignature object

isIncomplete

public boolean isIncomplete()

Description copied from class: Signature

Check if this signature is missing information.

Specified by:

isIncomplete in class Signature

calculateFqn

protected java.lang.String calculateFqn()

Specified by:

calculateFqn in class Signature

calculatePrettyFqn

protected java.lang.String calculatePrettyFqn()

Specified by:

calculatePrettyFqn in class Signature

clearCache

public static void clearCache()

Remove all currently cached MethodSignature objects from the cache, allowing them to be removed by the garbage collector.

matchesIgnoreNull

public static boolean matchesIgnoreNull(MethodSignature signature,
                                        MethodSignature wildcard)

Fuzzy check if two MethodSignature objects are equal. If any pattern field is null, its value in the matched object does not influence the check result, providing a way to create a wildcard MethodSignature that e.g. matches several methods of a class that have the same name but a different MethodDescriptor.

Parameters:

signature - The MethodSignature to be compared

wildcard - The MethodSignature pattern to be matched against

Returns:

true if the two objects match

matchesIgnoreNullAndDollar

public static boolean matchesIgnoreNullAndDollar(MethodSignature signature,
                                                 MethodSignature wildcard)

Fuzzy check like .matchesIgnoreNull(MethodSignature) but allows dollar signs in type strings. Usually the notation for inner classes is com/example/Foo$Bar, but sometimes external systems call this class com/example/Foo/Bar. These two names correspond to the same class and thus should be treated as the same if they appear in a MethodSignature. If it is to be expected that this situation may occur, this method should be preferred over .matchesIgnoreNull(MethodSignature) to avoid false negatives.

Parameters:

signature - The MethodSignature to be compared

wildcard - The MethodSignature pattern to be matched against

Returns:

true if the two objects match

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class Signature

getMethodName

@Nullable
public @Nullable java.lang.String getMethodName()

Description copied from interface: MethodInfo

Returns the method's name.

Specified by:

getMethodName in interface MethodInfo

getDescriptor

@Nullable
public @Nullable MethodDescriptor getDescriptor()

Description copied from interface: MethodInfo

Returns the method's descriptor.

Specified by:

getDescriptor in interface MethodInfo