net.bytebuddy.agent.builder

Class AgentBuilder.Default.ExecutingTransformer

java.lang.Object

net.bytebuddy.agent.builder.ResettableClassFileTransformer.AbstractBase

net.bytebuddy.agent.builder.AgentBuilder.Default.ExecutingTransformer

All Implemented Interfaces:

ClassFileTransformer, ResettableClassFileTransformer

Enclosing class:

AgentBuilder.Default

protected static class AgentBuilder.Default.ExecutingTransformer
extends ResettableClassFileTransformer.AbstractBase

A ClassFileTransformer that implements the enclosing agent builder's configuration.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static interface	AgentBuilder.Default.ExecutingTransformer.Factory A factory for creating a ClassFileTransformer for the current VM.
protected class	AgentBuilder.Default.ExecutingTransformer.Java9CapableVmDispatcher A privileged action for transforming a class on a JVM that supports modules.
protected class	AgentBuilder.Default.ExecutingTransformer.LegacyVmDispatcher A privileged action for transforming a class on a JVM prior to Java 9.

Nested classes/interfaces inherited from interface net.bytebuddy.agent.builder.ResettableClassFileTransformer

ResettableClassFileTransformer.AbstractBase, ResettableClassFileTransformer.Substitutable, ResettableClassFileTransformer.WithDelegation

Field Summary

Fields

Modifier and Type	Field and Description
protected static AgentBuilder.Default.ExecutingTransformer.Factory	FACTORY A factory for creating a ClassFileTransformer that supports the features of the current VM.

Constructor Summary

Constructors

Constructor and Description

ExecutingTransformer(ByteBuddy byteBuddy, AgentBuilder.Listener listener, AgentBuilder.PoolStrategy poolStrategy, AgentBuilder.TypeStrategy typeStrategy, AgentBuilder.LocationStrategy locationStrategy, ClassFileLocator classFileLocator, AgentBuilder.Default.NativeMethodStrategy nativeMethodStrategy, AgentBuilder.InitializationStrategy initializationStrategy, AgentBuilder.InjectionStrategy injectionStrategy, AgentBuilder.LambdaInstrumentationStrategy lambdaInstrumentationStrategy, AgentBuilder.DescriptionStrategy descriptionStrategy, AgentBuilder.FallbackStrategy fallbackStrategy, AgentBuilder.ClassFileBufferStrategy classFileBufferStrategy, AgentBuilder.InstallationListener installationListener, AgentBuilder.RawMatcher ignoreMatcher, AgentBuilder.RedefinitionStrategy.ResubmissionEnforcer resubmissionEnforcer, List<AgentBuilder.Default.Transformation> transformations, AgentBuilder.CircularityLock circularityLock) Creates a new class file transformer.

Method Summary

Modifier and Type	Method and Description
Iterator<AgentBuilder.Transformer>	iterator(TypeDescription typeDescription, ClassLoader classLoader, JavaModule module, Class<?> classBeingRedefined, ProtectionDomain protectionDomain) Creates an iterator over the transformers that are applied for a given type.
boolean	reset(Instrumentation instrumentation, ResettableClassFileTransformer classFileTransformer, AgentBuilder.RedefinitionStrategy redefinitionStrategy, AgentBuilder.RedefinitionStrategy.DiscoveryStrategy redefinitionDiscoveryStrategy, AgentBuilder.RedefinitionStrategy.BatchAllocator redefinitionBatchAllocator, AgentBuilder.RedefinitionStrategy.Listener redefinitionListener) Deregisters this class file transformer and redefines any transformed class to its state without this class file transformer applied, if the supplied redefinition strategy is enabled.
byte[]	transform(ClassLoader classLoader, String internalTypeName, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] binaryRepresentation)
protected byte[]	transform(Object rawModule, ClassLoader classLoader, String internalTypeName, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] binaryRepresentation) Applies a transformation for a class that was captured by this ClassFileTransformer.

Methods inherited from class net.bytebuddy.agent.builder.ResettableClassFileTransformer.AbstractBase

reset, reset, reset, reset, reset, reset, reset

Methods inherited from class java.lang.Object

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

Field Detail

FACTORY

protected static final AgentBuilder.Default.ExecutingTransformer.Factory FACTORY

A factory for creating a ClassFileTransformer that supports the features of the current VM.

Constructor Detail

ExecutingTransformer

public ExecutingTransformer(ByteBuddy byteBuddy,
                            AgentBuilder.Listener listener,
                            AgentBuilder.PoolStrategy poolStrategy,
                            AgentBuilder.TypeStrategy typeStrategy,
                            AgentBuilder.LocationStrategy locationStrategy,
                            ClassFileLocator classFileLocator,
                            AgentBuilder.Default.NativeMethodStrategy nativeMethodStrategy,
                            AgentBuilder.InitializationStrategy initializationStrategy,
                            AgentBuilder.InjectionStrategy injectionStrategy,
                            AgentBuilder.LambdaInstrumentationStrategy lambdaInstrumentationStrategy,
                            AgentBuilder.DescriptionStrategy descriptionStrategy,
                            AgentBuilder.FallbackStrategy fallbackStrategy,
                            AgentBuilder.ClassFileBufferStrategy classFileBufferStrategy,
                            AgentBuilder.InstallationListener installationListener,
                            AgentBuilder.RawMatcher ignoreMatcher,
                            AgentBuilder.RedefinitionStrategy.ResubmissionEnforcer resubmissionEnforcer,
                            List<AgentBuilder.Default.Transformation> transformations,
                            AgentBuilder.CircularityLock circularityLock)

Creates a new class file transformer.

Parameters:

byteBuddy - The Byte Buddy instance to be used.

listener - The listener to notify on transformations.

poolStrategy - The pool strategy to use.

typeStrategy - The definition handler to use.

locationStrategy - The location strategy to use.

classFileLocator - A class file locator for locating globally available types.

nativeMethodStrategy - The native method strategy to apply.

initializationStrategy - The initialization strategy to use for transformed types.

injectionStrategy - The injection strategy to use.

lambdaInstrumentationStrategy - The lambda instrumentation strategy to use.

descriptionStrategy - The description strategy for resolving type descriptions for types.

fallbackStrategy - The fallback strategy to use.

installationListener - The installation listener to notify.

classFileBufferStrategy - The class file buffer strategy to use.

ignoreMatcher - Identifies types that should not be instrumented.

resubmissionEnforcer - The resubmission enforcer to use.

transformations - The transformations to apply on non-ignored types.

circularityLock - The circularity lock to use.

Method Detail

transform

@MaybeNull
public byte[] transform(@MaybeNull
                                   ClassLoader classLoader,
                                   @MaybeNull
                                   String internalTypeName,
                                   @MaybeNull
                                   Class<?> classBeingRedefined,
                                   ProtectionDomain protectionDomain,
                                   byte[] binaryRepresentation)

transform

@MaybeNull
protected byte[] transform(Object rawModule,
                                      @MaybeNull
                                      ClassLoader classLoader,
                                      @MaybeNull
                                      String internalTypeName,
                                      @MaybeNull
                                      Class<?> classBeingRedefined,
                                      ProtectionDomain protectionDomain,
                                      byte[] binaryRepresentation)

Applies a transformation for a class that was captured by this ClassFileTransformer. Invoking this method allows to process module information which is available since Java 9.

Parameters:

rawModule - The instrumented class's Java java.lang.Module.

classLoader - The type's class loader or null if the type is loaded by the bootstrap loader.

internalTypeName - The internal name of the instrumented class.

classBeingRedefined - The loaded Class being redefined or null if no such class exists.

protectionDomain - The instrumented type's protection domain.

binaryRepresentation - The class file of the instrumented class in its current state.

Returns:

The transformed class file or an empty byte array if this transformer does not apply an instrumentation.

iterator

public Iterator<AgentBuilder.Transformer> iterator(TypeDescription typeDescription,
                                                   @MaybeNull
                                                   ClassLoader classLoader,
                                                   @MaybeNull
                                                   JavaModule module,
                                                   @MaybeNull
                                                   Class<?> classBeingRedefined,
                                                   ProtectionDomain protectionDomain)

Creates an iterator over the transformers that are applied for a given type.

Parameters:

typeDescription - A description of a type.

classLoader - The type's class loader or null if the boot loader.

module - The type's module or null if the module system is not supported by the current VM.

classBeingRedefined - The class being redefined or null if the type is not yet loaded.

protectionDomain - The type's protection domain.

Returns:

An iterator over the transformers that are applied by this class file transformer if the given type is discovered.

reset

public boolean reset(Instrumentation instrumentation,
                     ResettableClassFileTransformer classFileTransformer,
                     AgentBuilder.RedefinitionStrategy redefinitionStrategy,
                     AgentBuilder.RedefinitionStrategy.DiscoveryStrategy redefinitionDiscoveryStrategy,
                     AgentBuilder.RedefinitionStrategy.BatchAllocator redefinitionBatchAllocator,
                     AgentBuilder.RedefinitionStrategy.Listener redefinitionListener)

Deregisters this class file transformer and redefines any transformed class to its state without this class file transformer applied, if the supplied redefinition strategy is enabled. If it is not enabled, only the AgentBuilder.InstallationListener is informed about the resetting without undoing any code changes.

Note: A reset class file transformer should not be reinstalled. Instead, the AgentBuilder which built the transformer should be asked to install a new transformer.

Important: Most JVMs do not support changes of a class's structure after a class was already loaded. Therefore, it is typically required that this class file transformer was built while enabling AgentBuilder.disableClassFormatChanges().

Parameters:

instrumentation - The instrumentation instance from which to deregister the transformer.

classFileTransformer - The actual class file transformer to deregister which might be this instance or any wrapper.

redefinitionStrategy - The redefinition to apply.

redefinitionDiscoveryStrategy - The discovery strategy for the types to reset.

redefinitionBatchAllocator - The batch allocator to use.

redefinitionListener - The redefinition listener to apply.

Returns:

true if a reset was applied and this transformer was not previously removed.