package net.bytebuddy.implementation;
import lombok.EqualsAndHashCode;
import net.bytebuddy.ClassFileVersion;
import net.bytebuddy.description.annotation.AnnotationList;
import net.bytebuddy.description.annotation.AnnotationValue;
import net.bytebuddy.description.field.FieldDescription;
import net.bytebuddy.description.method.MethodDescription;
import net.bytebuddy.description.method.ParameterDescription;
import net.bytebuddy.description.method.ParameterList;
import net.bytebuddy.description.modifier.Visibility;
import net.bytebuddy.description.type.TypeDefinition;
import net.bytebuddy.description.type.TypeDescription;
import net.bytebuddy.description.type.TypeList;
import net.bytebuddy.dynamic.DynamicType;
import net.bytebuddy.dynamic.scaffold.InstrumentedType;
import net.bytebuddy.dynamic.scaffold.MethodGraph;
import net.bytebuddy.dynamic.scaffold.TypeInitializer;
import net.bytebuddy.dynamic.scaffold.TypeWriter;
import net.bytebuddy.implementation.attribute.AnnotationValueFilter;
import net.bytebuddy.implementation.auxiliary.AuxiliaryType;
import net.bytebuddy.implementation.bytecode.ByteCodeAppender;
import net.bytebuddy.implementation.bytecode.StackManipulation;
import net.bytebuddy.implementation.bytecode.member.FieldAccess;
import net.bytebuddy.implementation.bytecode.member.MethodInvocation;
import net.bytebuddy.implementation.bytecode.member.MethodReturn;
import net.bytebuddy.implementation.bytecode.member.MethodVariableAccess;
import net.bytebuddy.utility.RandomString;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import java.util.*;
/**
* An implementation is responsible for implementing methods of a dynamically created type as byte code. An
* implementation is applied in two stages:
* <ol>
* <li>The implementation is able to prepare an instrumented type by adding fields and/or helper methods that are
* required for the methods implemented by this implementation. Furthermore,
* {@link LoadedTypeInitializer}s and byte code for the type initializer can be registered for the instrumented
* type.</li>
* <li>Any implementation is required to supply a byte code appender that is responsible for providing the byte code
* to the instrumented methods that were delegated to this implementation. This byte code appender is also
* be responsible for providing implementations for the methods added in step <i>1</i>.</li>
* </ol>
* <p> </p>
* An implementation should provide meaningful implementations of both {@link java.lang.Object#equals(Object)}
* and {@link Object#hashCode()} if it wants to avoid to be used twice within the creation of a dynamic type. For two
* equal implementations only one will be applied on the creation of a dynamic type.
*/
public interface Implementation extends InstrumentedType.Prepareable {
/**
* Creates a byte code appender that determines the implementation of the instrumented type's methods.
*
* @param implementationTarget The target of the current implementation.
* @return A byte code appender for implementing methods delegated to this implementation. This byte code appender
* is also responsible for handling methods that were added by this implementation on the call to
* {@link Implementation#prepare(InstrumentedType)}.
*/
ByteCodeAppender appender(Target implementationTarget);
/**
* Represents an implementation that can be chained together with another implementation.
*/
interface Composable extends Implementation {
/**
* Appends the supplied implementation to this implementation.
*
* @param implementation The subsequent implementation.
* @return An implementation that combines this implementation with the provided one.
*/
Implementation andThen(Implementation implementation);
}
/**
* Represents an type-specific method invocation on the current instrumented type which is not legal from outside
* the type such as a super method or default method invocation. Legal instances of special method invocations must
* be equal to one another if they represent the same invocation target.
*/
interface SpecialMethodInvocation extends StackManipulation {
/**
* Returns the method that represents this special method invocation. This method can be different even for
* equal special method invocations, dependant on the method that was used to request such an invocation by the
* means of a {@link Implementation.Target}.
*
* @return The method description that describes this instances invocation target.
*/
MethodDescription getMethodDescription();
/**
* Returns the target type the represented method is invoked on.
*
* @return The type the represented method is invoked on.
*/
TypeDescription getTypeDescription();
/**
* A canonical implementation of an illegal {@link Implementation.SpecialMethodInvocation}.
*/
enum Illegal implements SpecialMethodInvocation {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public boolean isValid() {
return false;
}
@Override
public Size apply(MethodVisitor methodVisitor, Context implementationContext) {
throw new IllegalStateException("Cannot implement an undefined method");
}
@Override
public MethodDescription getMethodDescription() {
throw new IllegalStateException("An illegal special method invocation must not be applied");
}
@Override
public TypeDescription getTypeDescription() {
throw new IllegalStateException("An illegal special method invocation must not be applied");
}
}
/**
* An abstract base implementation of a valid special method invocation.
*/
abstract class AbstractBase implements SpecialMethodInvocation {
@Override
public boolean isValid() {
return true;
}
@Override
public int hashCode() {
return 31 * getMethodDescription().asSignatureToken().hashCode() + getTypeDescription().hashCode();
}
@Override
public boolean equals(Object other) {
if (this == other) return true;
if (!(other instanceof SpecialMethodInvocation)) return false;
SpecialMethodInvocation specialMethodInvocation = (SpecialMethodInvocation) other;
return getMethodDescription().asSignatureToken().equals(specialMethodInvocation.getMethodDescription().asSignatureToken())
&& getTypeDescription().equals(((SpecialMethodInvocation) other).getTypeDescription());
}
}
/**
* A canonical implementation of a {@link SpecialMethodInvocation}.
*/
class Simple extends SpecialMethodInvocation.AbstractBase {
/**
* The method description that is represented by this legal special method invocation.
*/
private final MethodDescription methodDescription;
/**
* The type description that is represented by this legal special method invocation.
*/
private final TypeDescription typeDescription;
/**
* A stack manipulation representing the method's invocation on the type description.
*/
private final StackManipulation stackManipulation;
/**
* Creates a new legal special method invocation.
*
* @param methodDescription The method that represents the special method invocation.
* @param typeDescription The type on which the method should be invoked on by an {@code INVOKESPECIAL}
* invocation.
* @param stackManipulation The stack manipulation that represents this special method invocation.
*/
protected Simple(MethodDescription methodDescription, TypeDescription typeDescription, StackManipulation stackManipulation) {
this.methodDescription = methodDescription;
this.typeDescription = typeDescription;
this.stackManipulation = stackManipulation;
}
/**
* Creates a special method invocation for a given invocation target.
*
* @param methodDescription The method that represents the special method invocation.
* @param typeDescription The type on which the method should be invoked on by an {@code INVOKESPECIAL}
* invocation.
* @return A special method invocation representing a legal invocation if the method can be invoked
* specially on the target type or an illegal invocation if this is not possible.
*/
public static SpecialMethodInvocation of(MethodDescription methodDescription, TypeDescription typeDescription) {
StackManipulation stackManipulation = MethodInvocation.invoke(methodDescription).special(typeDescription);
return stackManipulation.isValid()
? new Simple(methodDescription, typeDescription, stackManipulation)
: SpecialMethodInvocation.Illegal.INSTANCE;
}
@Override
public MethodDescription getMethodDescription() {
return methodDescription;
}
@Override
public TypeDescription getTypeDescription() {
return typeDescription;
}
@Override
public Size apply(MethodVisitor methodVisitor, Context implementationContext) {
return stackManipulation.apply(methodVisitor, implementationContext);
}
}
}
/**
* The target of an implementation. Implementation targets must be immutable and can be queried without altering
* the implementation result. An implementation target provides information on the type that is to be created
* where it is the implementation's responsibility to cache expensive computations, especially such computations
* that require reflective look-up.
*/
interface Target {
/**
* Returns a description of the instrumented type.
*
* @return A description of the instrumented type.
*/
TypeDescription getInstrumentedType();
/**
* Identifies the origin type of an implementation. The origin type describes the type that is subject to
* any form of enhancement. If a subclass of a given type is generated, the base type of this subclass
* describes the origin type. If a given type is redefined or rebased, the origin type is described by the
* instrumented type itself.
*
* @return The origin type of this implementation.
*/
TypeDefinition getOriginType();
/**
* Creates a special method invocation for invoking the super method of the given method.
*
* @param token A token of the method that is to be invoked as a super method.
* @return The corresponding special method invocation which might be illegal if the requested invocation is not legal.
*/
SpecialMethodInvocation invokeSuper(MethodDescription.SignatureToken token);
/**
* Creates a special method invocation for invoking a default method with the given token. The default method call must
* not be ambiguous or an illegal special method invocation is returned.
*
* @param token A token of the method that is to be invoked as a default method.
* @return The corresponding default method invocation which might be illegal if the requested invocation is not legal or ambiguous.
*/
SpecialMethodInvocation invokeDefault(MethodDescription.SignatureToken token);
/**
* Creates a special method invocation for invoking a default method.
*
* @param targetType The interface on which the default method is to be invoked.
* @param token A token that uniquely describes the method to invoke.
* @return The corresponding special method invocation which might be illegal if the requested invocation is
* not legal.
*/
SpecialMethodInvocation invokeDefault(MethodDescription.SignatureToken token, TypeDescription targetType);
/**
* Invokes a dominant method, i.e. if the method token can be invoked as a super method invocation, this invocation is considered dominant.
* Alternatively, a method invocation is attempted on an interface type as a default method invocation only if this invocation is not ambiguous
* for several interfaces.
*
* @param token The method token representing the method to be invoked.
* @return A special method invocation for a method representing the method token.
*/
SpecialMethodInvocation invokeDominant(MethodDescription.SignatureToken token);
/**
* A factory for creating an {@link Implementation.Target}.
*/
interface Factory {
/**
* Creates an implementation target.
*
* @param instrumentedType The instrumented type.
* @param methodGraph A method graph of the instrumented type.
* @param classFileVersion The type's class file version.
* @return An implementation target for the instrumented type.
*/
Target make(TypeDescription instrumentedType, MethodGraph.Linked methodGraph, ClassFileVersion classFileVersion);
}
/**
* An abstract base implementation for an {@link Implementation.Target}.
*/
@EqualsAndHashCode
abstract class AbstractBase implements Target {
/**
* The instrumented type.
*/
protected final TypeDescription instrumentedType;
/**
* The instrumented type's method graph.
*/
protected final MethodGraph.Linked methodGraph;
/**
* The default method invocation mode to apply.
*/
protected final DefaultMethodInvocation defaultMethodInvocation;
/**
* Creates a new implementation target.
*
* @param instrumentedType The instrumented type.
* @param methodGraph The instrumented type's method graph.
* @param defaultMethodInvocation The default method invocation mode to apply.
*/
protected AbstractBase(TypeDescription instrumentedType, MethodGraph.Linked methodGraph, DefaultMethodInvocation defaultMethodInvocation) {
this.instrumentedType = instrumentedType;
this.methodGraph = methodGraph;
this.defaultMethodInvocation = defaultMethodInvocation;
}
@Override
public TypeDescription getInstrumentedType() {
return instrumentedType;
}
@Override
public SpecialMethodInvocation invokeDefault(MethodDescription.SignatureToken token) {
SpecialMethodInvocation specialMethodInvocation = SpecialMethodInvocation.Illegal.INSTANCE;
for (TypeDescription interfaceType : instrumentedType.getInterfaces().asErasures()) {
SpecialMethodInvocation invocation = invokeDefault(token, interfaceType);
if (invocation.isValid()) {
if (specialMethodInvocation.isValid()) {
return SpecialMethodInvocation.Illegal.INSTANCE;
} else {
specialMethodInvocation = invocation;
}
}
}
return specialMethodInvocation;
}
@Override
public SpecialMethodInvocation invokeDefault(MethodDescription.SignatureToken token, TypeDescription targetType) {
return defaultMethodInvocation.apply(methodGraph.getInterfaceGraph(targetType).locate(token), targetType);
}
@Override
public SpecialMethodInvocation invokeDominant(MethodDescription.SignatureToken token) {
SpecialMethodInvocation specialMethodInvocation = invokeSuper(token);
return specialMethodInvocation.isValid()
? specialMethodInvocation
: invokeDefault(token);
}
/**
* Determines if default method invocations are possible.
*/
protected enum DefaultMethodInvocation {
/**
* Permits default method invocations, if an interface declaring a default method is possible.
*/
ENABLED {
@Override
protected SpecialMethodInvocation apply(MethodGraph.Node node, TypeDescription targetType) {
return node.getSort().isUnique()
? SpecialMethodInvocation.Simple.of(node.getRepresentative(), targetType)
: SpecialMethodInvocation.Illegal.INSTANCE;
}
},
/**
* Does not permit default method invocations.
*/
DISABLED {
@Override
protected SpecialMethodInvocation apply(MethodGraph.Node node, TypeDescription targetType) {
return SpecialMethodInvocation.Illegal.INSTANCE;
}
};
/**
* Resolves a default method invocation depending on the class file version permitting such calls.
*
* @param classFileVersion The class file version to resolve for.
* @return A suitable default method invocation mode.
*/
public static DefaultMethodInvocation of(ClassFileVersion classFileVersion) {
return classFileVersion.isAtLeast(ClassFileVersion.JAVA_V8)
? ENABLED
: DISABLED;
}
/**
* Resolves a default method invocation for a given node.
*
* @param node The node representing the default method call.
* @param targetType The target type defining the default method.
* @return A suitable special method invocation.
*/
protected abstract SpecialMethodInvocation apply(MethodGraph.Node node, TypeDescription targetType);
}
}
}
/**
* The context for an implementation application. An implementation context represents a mutable data structure
* where any registration is irrevocable. Calling methods on an implementation context should be considered equally
* sensitive as calling a {@link org.objectweb.asm.MethodVisitor}. As such, an implementation context and a
* {@link org.objectweb.asm.MethodVisitor} are complementary for creating an new Java type.
*/
interface Context extends MethodAccessorFactory {
/**
* Registers an auxiliary type as required for the current implementation. Registering a type will cause the
* creation of this type even if this type is not effectively used for the current implementation.
*
* @param auxiliaryType The auxiliary type that is required for the current implementation.
* @return A description of the registered auxiliary type.
*/
TypeDescription register(AuxiliaryType auxiliaryType);
/**
* Caches a single value by storing it in form of a {@code private}, {@code final} and {@code static} field.
* By caching values, expensive instance creations can be avoided and object identity can be preserved.
* The field is initiated in a generated class's static initializer.
*
* @param fieldValue A stack manipulation for creating the value that is to be cached in a {@code static} field.
* After executing the stack manipulation, exactly one value must be put onto the operand
* stack which is assignable to the given {@code fieldType}.
* @param fieldType The type of the field for storing the cached value. This field's type determines the value
* that is put onto the operand stack by this method's returned stack manipulation.
* @return A description of a field that was defined on the instrumented type which contains the given value.
*/
FieldDescription.InDefinedShape cache(StackManipulation fieldValue, TypeDescription fieldType);
/**
* Returns the instrumented type of the current implementation. The instrumented type is exposed with the intend of allowing optimal
* byte code generation and not for implementing checks or changing the behavior of a {@link StackManipulation}.
*
* @return The instrumented type of the current implementation.
*/
TypeDescription getInstrumentedType();
/**
* Returns the class file version of the currently created dynamic type.
*
* @return The class file version of the currently created dynamic type.
*/
ClassFileVersion getClassFileVersion();
/**
* Represents an extractable view of an {@link Implementation.Context} which
* allows the retrieval of any registered auxiliary type.
*/
interface ExtractableView extends Context {
/**
* Returns {@code true} if this implementation context permits the registration of any implicit type initializers.
*
* @return {@code true} if this implementation context permits the registration of any implicit type initializers.
*/
boolean isEnabled();
/**
* Returns any {@link net.bytebuddy.implementation.auxiliary.AuxiliaryType} that was registered
* with this {@link Implementation.Context}.
*
* @return A list of all manifested registered auxiliary types.
*/
List<DynamicType> getAuxiliaryTypes();
/**
* Writes any information that was registered with an {@link Implementation.Context}
* to the provided class visitor. This contains any fields for value caching, any accessor method and it
* writes the type initializer. The type initializer must therefore never be written manually.
*
* @param drain The drain to write the type initializer to.
* @param classVisitor The class visitor to which the extractable view is to be written.
* @param annotationValueFilterFactory The annotation value filter factory to apply when writing annotation.
*/
void drain(TypeInitializer.Drain drain, ClassVisitor classVisitor, AnnotationValueFilter.Factory annotationValueFilterFactory);
/**
* An abstract base implementation of an extractable view of an implementation context.
*/
@EqualsAndHashCode
abstract class AbstractBase implements ExtractableView {
/**
* The instrumented type.
*/
protected final TypeDescription instrumentedType;
/**
* The class file version of the dynamic type.
*/
protected final ClassFileVersion classFileVersion;
/**
* Create a new extractable view.
*
* @param instrumentedType The instrumented type.
* @param classFileVersion The class file version of the dynamic type.
*/
protected AbstractBase(TypeDescription instrumentedType, ClassFileVersion classFileVersion) {
this.instrumentedType = instrumentedType;
this.classFileVersion = classFileVersion;
}
@Override
public TypeDescription getInstrumentedType() {
return instrumentedType;
}
@Override
public ClassFileVersion getClassFileVersion() {
return classFileVersion;
}
}
}
/**
* A factory for creating a new implementation context.
*/
interface Factory {
/**
* Creates a new implementation context.
*
* @param instrumentedType The description of the type that is currently subject of creation.
* @param auxiliaryTypeNamingStrategy The naming strategy for naming an auxiliary type.
* @param typeInitializer The type initializer of the created instrumented type.
* @param classFileVersion The class file version of the created class.
* @param auxiliaryClassFileVersion The class file version of any auxiliary classes.
* @return An implementation context in its extractable view.
*/
ExtractableView make(TypeDescription instrumentedType,
AuxiliaryType.NamingStrategy auxiliaryTypeNamingStrategy,
TypeInitializer typeInitializer,
ClassFileVersion classFileVersion,
ClassFileVersion auxiliaryClassFileVersion);
}
/**
* An implementation context that does not allow for any injections into the static initializer block. This can be useful when
* redefining a class when it is not allowed to add methods to a class what is an implicit requirement when copying the static
* initializer block into another method.
*/
class Disabled extends ExtractableView.AbstractBase {
/**
* Creates a new disabled implementation context.
*
* @param instrumentedType The instrumented type.
* @param classFileVersion The class file version to create the class in.
*/
protected Disabled(TypeDescription instrumentedType, ClassFileVersion classFileVersion) {
super(instrumentedType, classFileVersion);
}
@Override
public boolean isEnabled() {
return false;
}
@Override
public List<DynamicType> getAuxiliaryTypes() {
return Collections.emptyList();
}
@Override
public void drain(TypeInitializer.Drain drain, ClassVisitor classVisitor, AnnotationValueFilter.Factory annotationValueFilterFactory) {
drain.apply(classVisitor, TypeInitializer.None.INSTANCE, this);
}
@Override
public TypeDescription register(AuxiliaryType auxiliaryType) {
throw new IllegalStateException("Registration of auxiliary types was disabled: " + auxiliaryType);
}
@Override
public MethodDescription.InDefinedShape registerAccessorFor(SpecialMethodInvocation specialMethodInvocation, AccessType accessType) {
throw new IllegalStateException("Registration of method accessors was disabled: " + specialMethodInvocation.getMethodDescription());
}
@Override
public MethodDescription.InDefinedShape registerGetterFor(FieldDescription fieldDescription, AccessType accessType) {
throw new IllegalStateException("Registration of field accessor was disabled: " + fieldDescription);
}
@Override
public MethodDescription.InDefinedShape registerSetterFor(FieldDescription fieldDescription, AccessType accessType) {
throw new IllegalStateException("Registration of field accessor was disabled: " + fieldDescription);
}
@Override
public FieldDescription.InDefinedShape cache(StackManipulation fieldValue, TypeDescription fieldType) {
throw new IllegalStateException("Field values caching was disabled: " + fieldType);
}
/**
* A factory for creating a {@link net.bytebuddy.implementation.Implementation.Context.Disabled}.
*/
public enum Factory implements Context.Factory {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public ExtractableView make(TypeDescription instrumentedType,
AuxiliaryType.NamingStrategy auxiliaryTypeNamingStrategy,
TypeInitializer typeInitializer,
ClassFileVersion classFileVersion,
ClassFileVersion auxiliaryClassFileVersion) {
if (typeInitializer.isDefined()) {
throw new IllegalStateException("Cannot define type initializer which was explicitly disabled: " + typeInitializer);
}
return new Disabled(instrumentedType, classFileVersion);
}
}
}
/**
* A default implementation of an {@link Implementation.Context.ExtractableView}
* which serves as its own {@link MethodAccessorFactory}.
*/
class Default extends ExtractableView.AbstractBase {
/**
* The name suffix to be appended to an accessor method.
*/
public static final String ACCESSOR_METHOD_SUFFIX = "accessor";
/**
* The name prefix to be prepended to a field storing a cached value.
*/
public static final String FIELD_CACHE_PREFIX = "cachedValue";
/**
* The naming strategy for naming auxiliary types that are registered.
*/
private final AuxiliaryType.NamingStrategy auxiliaryTypeNamingStrategy;
/**
* The type initializer of the created instrumented type.
*/
private final TypeInitializer typeInitializer;
/**
* The class file version to use for auxiliary classes.
*/
private final ClassFileVersion auxiliaryClassFileVersion;
/**
* A mapping of special method invocations to their accessor methods that each invoke their mapped invocation.
*/
private final Map<SpecialMethodInvocation, DelegationRecord> registeredAccessorMethods;
/**
* The registered getters.
*/
private final Map<FieldDescription, DelegationRecord> registeredGetters;
/**
* The registered setters.
*/
private final Map<FieldDescription, DelegationRecord> registeredSetters;
/**
* A map of registered auxiliary types to their dynamic type representation.
*/
private final Map<AuxiliaryType, DynamicType> auxiliaryTypes;
/**
* A map of already registered field caches to their field representation.
*/
private final Map<FieldCacheEntry, FieldDescription.InDefinedShape> registeredFieldCacheEntries;
/**
* A random suffix to append to the names of accessor methods.
*/
private final String suffix;
/**
* If {@code false}, the type initializer for this instance was already drained what prohibits the registration of additional cached field values.
*/
private boolean fieldCacheCanAppendEntries;
/**
* Creates a new default implementation context.
*
* @param instrumentedType The description of the type that is currently subject of creation.
* @param classFileVersion The class file version of the created class.
* @param auxiliaryTypeNamingStrategy The naming strategy for naming an auxiliary type.
* @param typeInitializer The type initializer of the created instrumented type.
* @param auxiliaryClassFileVersion The class file version to use for auxiliary classes.
*/
protected Default(TypeDescription instrumentedType,
ClassFileVersion classFileVersion,
AuxiliaryType.NamingStrategy auxiliaryTypeNamingStrategy,
TypeInitializer typeInitializer,
ClassFileVersion auxiliaryClassFileVersion) {
super(instrumentedType, classFileVersion);
this.auxiliaryTypeNamingStrategy = auxiliaryTypeNamingStrategy;
this.typeInitializer = typeInitializer;
this.auxiliaryClassFileVersion = auxiliaryClassFileVersion;
registeredAccessorMethods = new HashMap<SpecialMethodInvocation, DelegationRecord>();
registeredGetters = new HashMap<FieldDescription, DelegationRecord>();
registeredSetters = new HashMap<FieldDescription, DelegationRecord>();
auxiliaryTypes = new HashMap<AuxiliaryType, DynamicType>();
registeredFieldCacheEntries = new HashMap<FieldCacheEntry, FieldDescription.InDefinedShape>();
suffix = RandomString.make();
fieldCacheCanAppendEntries = true;
}
@Override
public boolean isEnabled() {
return true;
}
@Override
public MethodDescription.InDefinedShape registerAccessorFor(SpecialMethodInvocation specialMethodInvocation, AccessType accessType) {
DelegationRecord record = registeredAccessorMethods.get(specialMethodInvocation);
record = record == null
? new AccessorMethodDelegation(instrumentedType, suffix, accessType, specialMethodInvocation)
: record.with(accessType);
registeredAccessorMethods.put(specialMethodInvocation, record);
return record.getMethod();
}
@Override
public MethodDescription.InDefinedShape registerGetterFor(FieldDescription fieldDescription, AccessType accessType) {
DelegationRecord record = registeredGetters.get(fieldDescription);
record = record == null
? new FieldGetterDelegation(instrumentedType, suffix, accessType, fieldDescription)
: record.with(accessType);
registeredGetters.put(fieldDescription, record);
return record.getMethod();
}
@Override
public MethodDescription.InDefinedShape registerSetterFor(FieldDescription fieldDescription, AccessType accessType) {
DelegationRecord record = registeredSetters.get(fieldDescription);
record = record == null
? new FieldSetterDelegation(instrumentedType, suffix, accessType, fieldDescription)
: record.with(accessType);
registeredSetters.put(fieldDescription, record);
return record.getMethod();
}
@Override
public TypeDescription register(AuxiliaryType auxiliaryType) {
DynamicType dynamicType = auxiliaryTypes.get(auxiliaryType);
if (dynamicType == null) {
dynamicType = auxiliaryType.make(auxiliaryTypeNamingStrategy.name(instrumentedType), auxiliaryClassFileVersion, this);
auxiliaryTypes.put(auxiliaryType, dynamicType);
}
return dynamicType.getTypeDescription();
}
@Override
public List<DynamicType> getAuxiliaryTypes() {
return new ArrayList<DynamicType>(auxiliaryTypes.values());
}
@Override
public FieldDescription.InDefinedShape cache(StackManipulation fieldValue, TypeDescription fieldType) {
FieldCacheEntry fieldCacheEntry = new FieldCacheEntry(fieldValue, fieldType);
FieldDescription.InDefinedShape fieldCache = registeredFieldCacheEntries.get(fieldCacheEntry);
if (fieldCache != null) {
return fieldCache;
}
if (!fieldCacheCanAppendEntries) {
throw new IllegalStateException("Cached values cannot be registered after defining the type initializer for " + instrumentedType);
}
fieldCache = new CacheValueField(instrumentedType, fieldType.asGenericType(), suffix, fieldValue.hashCode());
registeredFieldCacheEntries.put(fieldCacheEntry, fieldCache);
return fieldCache;
}
@Override
public void drain(TypeInitializer.Drain drain,
ClassVisitor classVisitor,
AnnotationValueFilter.Factory annotationValueFilterFactory) {
fieldCacheCanAppendEntries = false;
TypeInitializer typeInitializer = this.typeInitializer;
for (Map.Entry<FieldCacheEntry, FieldDescription.InDefinedShape> entry : registeredFieldCacheEntries.entrySet()) {
FieldVisitor fieldVisitor = classVisitor.visitField(entry.getValue().getModifiers(),
entry.getValue().getInternalName(),
entry.getValue().getDescriptor(),
entry.getValue().getGenericSignature(),
FieldDescription.NO_DEFAULT_VALUE);
if (fieldVisitor != null) {
fieldVisitor.visitEnd();
typeInitializer = typeInitializer.expandWith(entry.getKey().storeIn(entry.getValue()));
}
}
drain.apply(classVisitor, typeInitializer, this);
for (TypeWriter.MethodPool.Record record : registeredAccessorMethods.values()) {
record.apply(classVisitor, this, annotationValueFilterFactory);
}
for (TypeWriter.MethodPool.Record record : registeredGetters.values()) {
record.apply(classVisitor, this, annotationValueFilterFactory);
}
for (TypeWriter.MethodPool.Record record : registeredSetters.values()) {
record.apply(classVisitor, this, annotationValueFilterFactory);
}
}
/**
* A description of a field that stores a cached value.
*/
protected static class CacheValueField extends FieldDescription.InDefinedShape.AbstractBase {
/**
* The instrumented type.
*/
private final TypeDescription instrumentedType;
/**
* The type of the cache's field.
*/
private final TypeDescription.Generic fieldType;
/**
* The suffix to use for the cache field's name.
*/
private final String suffix;
/**
* The hash value of the field's value for creating a unique field name.
*/
private final int hashCode;
/**
* Creates a new cache value field.
*
* @param instrumentedType The instrumented type.
* @param fieldType The type of the cache's field.
* @param suffix The suffix to use for the cache field's name.
* @param hashCode The hash value of the field's value for creating a unique field name.
*/
protected CacheValueField(TypeDescription instrumentedType, TypeDescription.Generic fieldType, String suffix, int hashCode) {
this.instrumentedType = instrumentedType;
this.fieldType = fieldType;
this.suffix = suffix;
this.hashCode = hashCode;
}
@Override
public TypeDescription.Generic getType() {
return fieldType;
}
@Override
public AnnotationList getDeclaredAnnotations() {
return new AnnotationList.Empty();
}
@Override
public TypeDescription getDeclaringType() {
return instrumentedType;
}
@Override
public int getModifiers() {
return Opcodes.ACC_SYNTHETIC | Opcodes.ACC_FINAL | Opcodes.ACC_STATIC | (instrumentedType.isInterface()
? Opcodes.ACC_PUBLIC
: Opcodes.ACC_PRIVATE);
}
@Override
public String getName() {
return String.format("%s$%s$%s", FIELD_CACHE_PREFIX, suffix, RandomString.hashOf(hashCode));
}
}
/**
* A field cache entry for uniquely identifying a cached field. A cached field is described by the stack
* manipulation that loads the field's value onto the operand stack and the type of the field.
*/
@EqualsAndHashCode
protected static class FieldCacheEntry implements StackManipulation {
/**
* The field value that is represented by this field cache entry.
*/
private final StackManipulation fieldValue;
/**
* The field type that is represented by this field cache entry.
*/
private final TypeDescription fieldType;
/**
* Creates a new field cache entry.
*
* @param fieldValue The field value that is represented by this field cache entry.
* @param fieldType The field type that is represented by this field cache entry.
*/
protected FieldCacheEntry(StackManipulation fieldValue, TypeDescription fieldType) {
this.fieldValue = fieldValue;
this.fieldType = fieldType;
}
/**
* Returns a stack manipulation where the represented value is stored in the given field.
*
* @param fieldDescription A static field in which the value is to be stored.
* @return A byte code appender that represents this storage.
*/
protected ByteCodeAppender storeIn(FieldDescription fieldDescription) {
return new ByteCodeAppender.Simple(this, FieldAccess.forField(fieldDescription).write());
}
/**
* Returns the field type that is represented by this field cache entry.
*
* @return The field type that is represented by this field cache entry.
*/
protected TypeDescription getFieldType() {
return fieldType;
}
@Override
public boolean isValid() {
return fieldValue.isValid();
}
@Override
public Size apply(MethodVisitor methodVisitor, Context implementationContext) {
return fieldValue.apply(methodVisitor, implementationContext);
}
}
/**
* A base implementation of a method that accesses a property of an instrumented type.
*/
protected abstract static class AbstractPropertyAccessorMethod extends MethodDescription.InDefinedShape.AbstractBase {
@Override
public int getModifiers() {
return Opcodes.ACC_SYNTHETIC | getBaseModifiers() | (getDeclaringType().isInterface()
? Opcodes.ACC_PUBLIC
: Opcodes.ACC_FINAL);
}
/**
* Returns the base modifiers, i.e. the modifiers that define the accessed property's features.
*
* @return Returns the base modifiers of the represented methods.
*/
protected abstract int getBaseModifiers();
}
/**
* A description of an accessor method to access another method from outside the instrumented type.
*/
protected static class AccessorMethod extends AbstractPropertyAccessorMethod {
/**
* The instrumented type.
*/
private final TypeDescription instrumentedType;
/**
* The method that is being accessed.
*/
private final MethodDescription methodDescription;
/**
* The suffix to append to the accessor method's name.
*/
private final String suffix;
/**
* Creates a new accessor method.
*
* @param instrumentedType The instrumented type.
* @param methodDescription The method that is being accessed.
* @param suffix The suffix to append to the accessor method's name.
*/
protected AccessorMethod(TypeDescription instrumentedType, MethodDescription methodDescription, String suffix) {
this.instrumentedType = instrumentedType;
this.methodDescription = methodDescription;
this.suffix = suffix;
}
@Override
public TypeDescription.Generic getReturnType() {
return methodDescription.getReturnType().asRawType();
}
@Override
public ParameterList<ParameterDescription.InDefinedShape> getParameters() {
return new ParameterList.Explicit.ForTypes(this, methodDescription.getParameters().asTypeList().asRawTypes());
}
@Override
public TypeList.Generic getExceptionTypes() {
return methodDescription.getExceptionTypes().asRawTypes();
}
@Override
public AnnotationValue<?, ?> getDefaultValue() {
return AnnotationValue.UNDEFINED;
}
@Override
public TypeList.Generic getTypeVariables() {
return new TypeList.Generic.Empty();
}
@Override
public AnnotationList getDeclaredAnnotations() {
return new AnnotationList.Empty();
}
@Override
public TypeDescription getDeclaringType() {
return instrumentedType;
}
@Override
public int getBaseModifiers() {
return methodDescription.isStatic()
? Opcodes.ACC_STATIC
: EMPTY_MASK;
}
@Override
public String getInternalName() {
return String.format("%s$%s$%s", methodDescription.getInternalName(), ACCESSOR_METHOD_SUFFIX, suffix);
}
}
/**
* A description of a field getter method.
*/
protected static class FieldGetter extends AbstractPropertyAccessorMethod {
/**
* The instrumented type.
*/
private final TypeDescription instrumentedType;
/**
* The field for which a getter is described.
*/
private final FieldDescription fieldDescription;
/**
* The name suffix for the field getter method.
*/
private final String suffix;
/**
* Creates a new field getter.
*
* @param instrumentedType The instrumented type.
* @param fieldDescription The field for which a getter is described.
* @param suffix The name suffix for the field getter method.
*/
protected FieldGetter(TypeDescription instrumentedType, FieldDescription fieldDescription, String suffix) {
this.instrumentedType = instrumentedType;
this.fieldDescription = fieldDescription;
this.suffix = suffix;
}
@Override
public TypeDescription.Generic getReturnType() {
return fieldDescription.getType().asRawType();
}
@Override
public ParameterList<ParameterDescription.InDefinedShape> getParameters() {
return new ParameterList.Empty<ParameterDescription.InDefinedShape>();
}
@Override
public TypeList.Generic getExceptionTypes() {
return new TypeList.Generic.Empty();
}
@Override
public AnnotationValue<?, ?> getDefaultValue() {
return AnnotationValue.UNDEFINED;
}
@Override
public TypeList.Generic getTypeVariables() {
return new TypeList.Generic.Empty();
}
@Override
public AnnotationList getDeclaredAnnotations() {
return new AnnotationList.Empty();
}
@Override
public TypeDescription getDeclaringType() {
return instrumentedType;
}
@Override
protected int getBaseModifiers() {
return fieldDescription.isStatic()
? Opcodes.ACC_STATIC
: EMPTY_MASK;
}
@Override
public String getInternalName() {
return String.format("%s$%s$%s", fieldDescription.getName(), ACCESSOR_METHOD_SUFFIX, suffix);
}
}
/**
* A description of a field setter method.
*/
protected static class FieldSetter extends AbstractPropertyAccessorMethod {
/**
* The instrumented type.
*/
private final TypeDescription instrumentedType;
/**
* The field for which a setter is described.
*/
private final FieldDescription fieldDescription;
/**
* The name suffix for the field setter method.
*/
private final String suffix;
/**
* Creates a new field setter.
*
* @param instrumentedType The instrumented type.
* @param fieldDescription The field for which a setter is described.
* @param suffix The name suffix for the field setter method.
*/
protected FieldSetter(TypeDescription instrumentedType, FieldDescription fieldDescription, String suffix) {
this.instrumentedType = instrumentedType;
this.fieldDescription = fieldDescription;
this.suffix = suffix;
}
@Override
public TypeDescription.Generic getReturnType() {
return TypeDescription.Generic.VOID;
}
@Override
public ParameterList<ParameterDescription.InDefinedShape> getParameters() {
return new ParameterList.Explicit.ForTypes(this, Collections.singletonList(fieldDescription.getType().asRawType()));
}
@Override
public TypeList.Generic getExceptionTypes() {
return new TypeList.Generic.Empty();
}
@Override
public AnnotationValue<?, ?> getDefaultValue() {
return AnnotationValue.UNDEFINED;
}
@Override
public TypeList.Generic getTypeVariables() {
return new TypeList.Generic.Empty();
}
@Override
public AnnotationList getDeclaredAnnotations() {
return new AnnotationList.Empty();
}
@Override
public TypeDescription getDeclaringType() {
return instrumentedType;
}
@Override
protected int getBaseModifiers() {
return fieldDescription.isStatic()
? Opcodes.ACC_STATIC
: EMPTY_MASK;
}
@Override
public String getInternalName() {
return String.format("%s$%s$%s", fieldDescription.getName(), ACCESSOR_METHOD_SUFFIX, suffix);
}
}
/**
* An abstract method pool entry that delegates the implementation of a method to itself.
*/
@EqualsAndHashCode(callSuper = false)
protected abstract static class DelegationRecord extends TypeWriter.MethodPool.Record.ForDefinedMethod implements ByteCodeAppender {
/**
* The delegation method.
*/
protected final MethodDescription.InDefinedShape methodDescription;
/**
* The record's visibility.
*/
protected final Visibility visibility;
/**
* Creates a new delegation record.
*
* @param methodDescription The delegation method.
* @param visibility The method's actual visibility.
*/
protected DelegationRecord(MethodDescription.InDefinedShape methodDescription, Visibility visibility) {
this.methodDescription = methodDescription;
this.visibility = visibility;
}
/**
* Returns this delegation record with the minimal visibility represented by the supplied access type.
*
* @param accessType The access type to enforce.
* @return A new version of this delegation record with the minimal implied visibility.
*/
protected abstract DelegationRecord with(AccessType accessType);
@Override
public MethodDescription.InDefinedShape getMethod() {
return methodDescription;
}
@Override
public Sort getSort() {
return Sort.IMPLEMENTED;
}
@Override
public Visibility getVisibility() {
return visibility;
}
@Override
public void applyHead(MethodVisitor methodVisitor) {
/* do nothing */
}
@Override
public void applyBody(MethodVisitor methodVisitor, Context implementationContext, AnnotationValueFilter.Factory annotationValueFilterFactory) {
methodVisitor.visitCode();
Size size = applyCode(methodVisitor, implementationContext);
methodVisitor.visitMaxs(size.getOperandStackSize(), size.getLocalVariableSize());
}
@Override
public void applyAttributes(MethodVisitor methodVisitor, AnnotationValueFilter.Factory annotationValueFilterFactory) {
/* do nothing */
}
@Override
public Size applyCode(MethodVisitor methodVisitor, Context implementationContext) {
return apply(methodVisitor, implementationContext, getMethod());
}
@Override
public TypeWriter.MethodPool.Record prepend(ByteCodeAppender byteCodeAppender) {
throw new UnsupportedOperationException("Cannot prepend code to a delegation for " + methodDescription);
}
}
/**
* An implementation of a {@link TypeWriter.MethodPool.Record} for implementing
* an accessor method.
*/
@EqualsAndHashCode(callSuper = true)
protected static class AccessorMethodDelegation extends DelegationRecord {
/**
* The stack manipulation that represents the requested special method invocation.
*/
private final StackManipulation accessorMethodInvocation;
/**
* Creates a delegation to an accessor method.
*
* @param instrumentedType The instrumented type.
* @param suffix The suffix to append to the method.
* @param accessType The access type.
* @param specialMethodInvocation The actual method's invocation.
*/
protected AccessorMethodDelegation(TypeDescription instrumentedType,
String suffix,
AccessType accessType,
SpecialMethodInvocation specialMethodInvocation) {
this(new AccessorMethod(instrumentedType, specialMethodInvocation.getMethodDescription(), suffix),
accessType.getVisibility(),
specialMethodInvocation);
}
/**
* Creates a delegation to an accessor method.
*
* @param methodDescription The accessor method.
* @param visibility The method's visibility.
* @param accessorMethodInvocation The actual method's invocation.
*/
private AccessorMethodDelegation(MethodDescription.InDefinedShape methodDescription,
Visibility visibility,
StackManipulation accessorMethodInvocation) {
super(methodDescription, visibility);
this.accessorMethodInvocation = accessorMethodInvocation;
}
@Override
protected DelegationRecord with(AccessType accessType) {
return new AccessorMethodDelegation(methodDescription, visibility.expandTo(accessType.getVisibility()), accessorMethodInvocation);
}
@Override
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext, MethodDescription instrumentedMethod) {
StackManipulation.Size stackSize = new StackManipulation.Compound(
MethodVariableAccess.allArgumentsOf(instrumentedMethod).prependThisReference(),
accessorMethodInvocation,
MethodReturn.of(instrumentedMethod.getReturnType())
).apply(methodVisitor, implementationContext);
return new Size(stackSize.getMaximalSize(), instrumentedMethod.getStackSize());
}
}
/**
* An implementation for a field getter.
*/
@EqualsAndHashCode(callSuper = true)
protected static class FieldGetterDelegation extends DelegationRecord {
/**
* The field to read from.
*/
private final FieldDescription fieldDescription;
/**
* Creates a new field getter implementation.
*
* @param instrumentedType The instrumented type.
* @param suffix The suffix to use for the setter method.
* @param accessType The method's access type.
* @param fieldDescription The field to write to.
*/
protected FieldGetterDelegation(TypeDescription instrumentedType, String suffix, AccessType accessType, FieldDescription fieldDescription) {
this(new FieldGetter(instrumentedType, fieldDescription, suffix), accessType.getVisibility(), fieldDescription);
}
/**
* Creates a new field getter implementation.
*
* @param methodDescription The delegation method.
* @param visibility The delegation method's visibility.
* @param fieldDescription The field to read.
*/
private FieldGetterDelegation(MethodDescription.InDefinedShape methodDescription, Visibility visibility, FieldDescription fieldDescription) {
super(methodDescription, visibility);
this.fieldDescription = fieldDescription;
}
@Override
protected DelegationRecord with(AccessType accessType) {
return new FieldGetterDelegation(methodDescription, visibility.expandTo(accessType.getVisibility()), fieldDescription);
}
@Override
public Size apply(MethodVisitor methodVisitor, Context implementationContext, MethodDescription instrumentedMethod) {
StackManipulation.Size stackSize = new StackManipulation.Compound(
fieldDescription.isStatic()
? StackManipulation.Trivial.INSTANCE
: MethodVariableAccess.loadThis(),
FieldAccess.forField(fieldDescription).read(),
MethodReturn.of(fieldDescription.getType())
).apply(methodVisitor, implementationContext);
return new Size(stackSize.getMaximalSize(), instrumentedMethod.getStackSize());
}
}
/**
* An implementation for a field setter.
*/
@EqualsAndHashCode(callSuper = true)
protected static class FieldSetterDelegation extends DelegationRecord {
/**
* The field to write to.
*/
private final FieldDescription fieldDescription;
/**
* Creates a new field setter implementation.
*
* @param instrumentedType The instrumented type.
* @param suffix The suffix to use for the setter method.
* @param accessType The method's access type.
* @param fieldDescription The field to write to.
*/
protected FieldSetterDelegation(TypeDescription instrumentedType, String suffix, AccessType accessType, FieldDescription fieldDescription) {
this(new FieldSetter(instrumentedType, fieldDescription, suffix), accessType.getVisibility(), fieldDescription);
}
/**
* Creates a new field setter.
*
* @param methodDescription The field accessor method.
* @param visibility The delegation method's visibility.
* @param fieldDescription The field to write to.
*/
private FieldSetterDelegation(MethodDescription.InDefinedShape methodDescription, Visibility visibility, FieldDescription fieldDescription) {
super(methodDescription, visibility);
this.fieldDescription = fieldDescription;
}
@Override
protected DelegationRecord with(AccessType accessType) {
return new FieldSetterDelegation(methodDescription, visibility.expandTo(accessType.getVisibility()), fieldDescription);
}
@Override
public Size apply(MethodVisitor methodVisitor, Context implementationContext, MethodDescription instrumentedMethod) {
StackManipulation.Size stackSize = new StackManipulation.Compound(
MethodVariableAccess.allArgumentsOf(instrumentedMethod).prependThisReference(),
FieldAccess.forField(fieldDescription).write(),
MethodReturn.VOID
).apply(methodVisitor, implementationContext);
return new Size(stackSize.getMaximalSize(), instrumentedMethod.getStackSize());
}
}
/**
* A factory for creating a {@link net.bytebuddy.implementation.Implementation.Context.Default}.
*/
public enum Factory implements ExtractableView.Factory {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public ExtractableView make(TypeDescription instrumentedType,
AuxiliaryType.NamingStrategy auxiliaryTypeNamingStrategy,
TypeInitializer typeInitializer,
ClassFileVersion classFileVersion,
ClassFileVersion auxiliaryClassFileVersion) {
return new Default(instrumentedType, classFileVersion, auxiliaryTypeNamingStrategy, typeInitializer, auxiliaryClassFileVersion);
}
}
}
}
/**
* A compound implementation that allows to combine several implementations.
* <p> </p>
* Note that the combination of two implementation might break the contract for implementing
* {@link java.lang.Object#equals(Object)} and {@link Object#hashCode()} as described for
* {@link Implementation}.
*
* @see Implementation
*/
@EqualsAndHashCode
class Compound implements Implementation {
/**
* All implementation that are represented by this compound implementation.
*/
private final List<Implementation> implementations;
/**
* Creates a new immutable compound implementation.
*
* @param implementation The implementations to combine in their order.
*/
public Compound(Implementation... implementation) {
this(Arrays.asList(implementation));
}
/**
* Creates a new immutable compound implementation.
*
* @param implementations The implementations to combine in their order.
*/
public Compound(List<? extends Implementation> implementations) {
this.implementations = new ArrayList<Implementation>();
for (Implementation implementation : implementations) {
if (implementation instanceof Compound) {
this.implementations.addAll(((Compound) implementation).implementations);
} else {
this.implementations.add(implementation);
}
}
}
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
for (Implementation implementation : implementations) {
instrumentedType = implementation.prepare(instrumentedType);
}
return instrumentedType;
}
@Override
public ByteCodeAppender appender(Target implementationTarget) {
ByteCodeAppender[] byteCodeAppender = new ByteCodeAppender[implementations.size()];
int index = 0;
for (Implementation implementation : implementations) {
byteCodeAppender[index++] = implementation.appender(implementationTarget);
}
return new ByteCodeAppender.Compound(byteCodeAppender);
}
}
/**
* A simple implementation that does not register any members with the instrumented type.
*/
@EqualsAndHashCode
class Simple implements Implementation {
/**
* The byte code appender to emmit.
*/
private final ByteCodeAppender byteCodeAppender;
/**
* Creates a new simple implementation for the given byte code appenders.
*
* @param byteCodeAppender The byte code appenders to apply in their order of application.
*/
public Simple(ByteCodeAppender... byteCodeAppender) {
this.byteCodeAppender = new ByteCodeAppender.Compound(byteCodeAppender);
}
/**
* Creates a new simple instrumentation for the given stack manipulations which are summarized in a
* byte code appender that defines any requested method by these manipulations.
*
* @param stackManipulation The stack manipulation to apply in their order of application.
*/
public Simple(StackManipulation... stackManipulation) {
byteCodeAppender = new ByteCodeAppender.Simple(stackManipulation);
}
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType;
}
@Override
public ByteCodeAppender appender(Target implementationTarget) {
return byteCodeAppender;
}
}
}