com.fitbur.bytebuddy.implementation.MethodDelegation Maven / Gradle / Ivy
package com.fitbur.bytebuddy.implementation;
import com.fitbur.bytebuddy.description.field.FieldDescription;
import com.fitbur.bytebuddy.description.method.MethodDescription;
import com.fitbur.bytebuddy.description.method.MethodList;
import com.fitbur.bytebuddy.description.type.TypeDefinition;
import com.fitbur.bytebuddy.description.type.TypeDescription;
import com.fitbur.bytebuddy.dynamic.scaffold.InstrumentedType;
import com.fitbur.bytebuddy.dynamic.scaffold.MethodGraph;
import com.fitbur.bytebuddy.implementation.bind.MethodDelegationBinder;
import com.fitbur.bytebuddy.implementation.bind.annotation.Argument;
import com.fitbur.bytebuddy.implementation.bind.annotation.TargetMethodAnnotationDrivenBinder;
import com.fitbur.bytebuddy.implementation.bytecode.ByteCodeAppender;
import com.fitbur.bytebuddy.implementation.bytecode.Duplication;
import com.fitbur.bytebuddy.implementation.bytecode.StackManipulation;
import com.fitbur.bytebuddy.implementation.bytecode.TypeCreation;
import com.fitbur.bytebuddy.implementation.bytecode.assign.Assigner;
import com.fitbur.bytebuddy.implementation.bytecode.member.FieldAccess;
import com.fitbur.bytebuddy.implementation.bytecode.member.MethodVariableAccess;
import com.fitbur.bytebuddy.matcher.ElementMatcher;
import com.fitbur.bytebuddy.utility.CompoundList;
import com.fitbur.bytebuddy.jar.asm.MethodVisitor;
import com.fitbur.bytebuddy.jar.asm.Opcodes;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.List;
import static com.fitbur.bytebuddy.matcher.ElementMatchers.*;
/**
* This implementation delegates an method call to another method which can either be {@code static} by providing
* a reference to a {@link java.lang.Class} or an instance method when another object is provided. The potential
* targets of the method delegation can further be filtered by applying a filter. The method delegation can be
* customized by invoking the {@code MethodDelegation}'s several builder methods.
* Without any customization, the method delegation will work as follows:
* Binding an instrumented method to a given delegate method
*
* A method will be bound parameter by parameter. Considering a method {@code Foo#bar} being bound to a method
* {@code Qux#baz}, the method delegation will be decided on basis of the following annotations:
*
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Argument}:
* This annotation will bind the {@code n}-th parameter of {@code Foo#bar} to that parameter of {@code Qux#baz}that
* is annotated with this annotation where {@code n} is the obligatory argument of the {@code @Argument} annotation.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.AllArguments}:
* This annotation will assign a collection of all parameters of {@code Foo#bar} to that parameter of {@code Qux#baz}
* that is annotated with {@code AllArguments}.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.This}: A parameter
* of {@code Qux#baz} that is annotated with {@code This} will be assigned the instance that is instrumented for
* a non-static method.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Super}: A parameter that is annotated with
* this annotation is assigned a proxy that allows calling an instrumented type's super methods.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Default}: A parameter that is annotated with
* this annotation is assigned a proxy that allows calling an instrumented type's directly implemented interfaces'
* default methods.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.SuperCall}: A parameter
* of {@code Qux#baz} that is annotated with {@code SuperCall} will be assigned an instance of a type implementing both
* {@link java.lang.Runnable} and {@link java.util.concurrent.Callable} which will invoke the instrumented method on the
* invocation of either interface's method. The call is made using the original arguments of the method invocation.
* The return value is only emitted for the {@link java.util.concurrent.Callable#call()} method which additionally
* requires to catch any unchecked exceptions that might be thrown by the original method's implementation. If a
* source method is abstract, using this annotation excludes the method with this parameter annotation from being bound
* to this source method.
*
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.DefaultCall}:
* This annotation is similar to the {@link com.fitbur.bytebuddy.implementation.bind.annotation.SuperCall}
* annotation but it invokes a default method that is compatible to this method. If a source method does not represent
* a default method, using this annotation excludes the method with this parameter annotation from being bound to this
* source method.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Origin}: A parameter of
* {@code Qux#baz} that is annotated with {@code Origin} is assigned a reference to either a {@link java.lang.reflect.Method},
* a {@link java.lang.reflect.Constructor}, a {@code java.lang.reflect.Executable} or a {@link java.lang.Class} instance.
* A {@code Method}-typed, {@code Constructor} or {@code Executable} parameter is assigned a reference to the original
* method that is instrumented. A {@code Class}-typed parameter is assigned the type of the caller. Furthermore, {@code MethodType}
* and {@code MethodHandle} parameters are also supported. When using the annotation on a {@link java.lang.String} type,
* the intercepted method's {@code toString} value is injected. The same holds for a parameter of type {@code int} that receives
* the modifiers of the instrumented method.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.StubValue}: Assigns the (boxed) default value of the
* intercepted method's return type to the parameter. If the return type is {@code void}, {@code null} is assigned.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Empty}: Assigns the parameter type's
* default value, i.e. {@code null} for a reference type or zero for primitive types. This is an opportunity to
* ignore a parameter.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Pipe}: A parameter that is annotated
* with this annotation is assigned a proxy for forwarding the source method invocation to another instance of the
* same type as the declaring type of the intercepted method. This annotation needs to be installed and explicitly
* registered before it can be used. See the {@link com.fitbur.bytebuddy.implementation.bind.annotation.Pipe}
* annotation's documentation for further information on how this can be done.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.Morph}: The morph annotation is similar to
* the {@link com.fitbur.bytebuddy.implementation.bind.annotation.SuperCall} annotation but allows to
* explicitly define and therewith alter the arguments that are handed to the super method. This annotation needs
* to be installed and explicitly registered before it can be used. See the documentation to the annotation for
* further information.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.FieldValue}: Allows to access a field's value at the time
* of the method invocation. The field's value is directly assigned to the annotated parameter.
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.FieldProxy}: Allows to access fields via getter
* and setter proxies. This annotation needs to be installed and explicitly registered before it can be used.
* Note that any field access requires boxing such that a use of {@link com.fitbur.bytebuddy.implementation.FieldAccessor} in
* combination with {@link com.fitbur.bytebuddy.implementation.MethodDelegation#andThen(Implementation)} might be a more
* performant alternative for implementing field getters and setters.
*
* If a method is not annotated with any of the above methods, it will be treated as if it was annotated
* {@link com.fitbur.bytebuddy.implementation.bind.annotation.Argument} using the next
* unbound parameter index of the source method as its parameter. This means that a method
* {@code Qux#baz(@Argument(2) Object p1, Object p2, @Argument(0) Object p3} would be treated as if {@code p2} was annotated
* with {@code @Argument(1)}.
*
* In addition, the {@link com.fitbur.bytebuddy.implementation.bind.annotation.RuntimeType}
* annotation can instruct a parameter to be bound by a
* {@link com.fitbur.bytebuddy.implementation.bytecode.assign.Assigner} with considering the
* runtime type of the parameter.
*
* Selecting among different methods that can be used for binding a method
* of the instrumented type
*
* When deciding between two methods {@code Foo#bar} and {@code Foo#qux} that could both be used to delegating a
* method call, the following consideration is applied in the given order:
*
* - {@link com.fitbur.bytebuddy.implementation.bind.annotation.BindingPriority}:
* A method that is annotated with this annotation is given a specific priority where the default priority is set
* to {@link com.fitbur.bytebuddy.implementation.bind.annotation.BindingPriority#DEFAULT}
* for non-annotated method. A method with a higher priority is considered a better target for delegation.
* - {@link com.fitbur.bytebuddy.implementation.bind.DeclaringTypeResolver}:
* If a target method is declared by a more specific type than another method, the method with the most specific
* type is bound.
* - {@link com.fitbur.bytebuddy.implementation.bind.MethodNameEqualityResolver}:
* If a source method {@code Baz#qux} is the source method, it will rather be assigned to {@code Foo#qux} because
* of their equal names. Similar names and case-insensitive equality are not considered.
* - {@link com.fitbur.bytebuddy.implementation.bind.ArgumentTypeResolver}:
* The most specific type resolver will consider all bindings that are using the
* {@link com.fitbur.bytebuddy.implementation.bind.annotation.Argument}
* annotation for resolving a binding conflict. In this context, the resolution will equal the most-specific
* type resolution that is performed by the Java compiler. This means that a source method {@code Bar#baz(String)}
* will rather be bound to a method {@code Foo#bar(String)} than {@code Foo#qux(Object)} because the {@code String}
* type is more specific than the {@code Object} type. If two methods are equally adequate by their parameter types,
* then the method with the higher numbers of {@code @Argument} annotated parameters is considered as the better
* delegation target.
* - {@link com.fitbur.bytebuddy.implementation.bind.ParameterLengthResolver}:
* If a target methods has a higher number of total parameters that were successfully bound, the method with
* the higher number will be considered as the better delegation target.
*
*
* Additionally, if a method is annotated by
* {@link com.fitbur.bytebuddy.implementation.bind.annotation.IgnoreForBinding},
* it is never considered as a target for a method delegation.
*
*
* Important: For invoking a method on another instance, use the {@link Forwarding} implementation. A method delegation
* intends to bind a interceptor class and its resolution algorithm will not necessarily yield a delegation to the intercepted
* method.
*
*
* @see Forwarding
*/
public class MethodDelegation implements Implementation.Composable {
/**
* The implementation delegate for this method delegation.
*/
private final ImplementationDelegate implementationDelegate;
/**
* A list of {@link com.fitbur.bytebuddy.implementation.bind.annotation.TargetMethodAnnotationDrivenBinder.ParameterBinder}s
* to be used by this method delegation.
*/
private final List> parameterBinders;
/**
* The {@link com.fitbur.bytebuddy.implementation.bind.annotation.TargetMethodAnnotationDrivenBinder.DefaultsProvider}
* to be used by this method delegation.
*/
private final TargetMethodAnnotationDrivenBinder.DefaultsProvider defaultsProvider;
/**
* The termination handler to apply.
*/
private final TargetMethodAnnotationDrivenBinder.TerminationHandler terminationHandler;
/**
* The {@link com.fitbur.bytebuddy.implementation.bind.MethodDelegationBinder.AmbiguityResolver}
* to be used by this method delegation.
*/
private final MethodDelegationBinder.AmbiguityResolver ambiguityResolver;
/**
* The {@link com.fitbur.bytebuddy.implementation.bytecode.assign.Assigner} to be used by this method delegation.
*/
private final Assigner assigner;
/**
* A method container to query for methods to be considered for delegation.
*/
private final MethodContainer methodContainer;
/**
* Creates a new method delegation.
*
* @param implementationDelegate The implementation delegate to use by this method delegator.
* @param parameterBinders The parameter binders to use by this method delegator.
* @param defaultsProvider The defaults provider to use by this method delegator.
* @param terminationHandler The termination handler to apply.
* @param ambiguityResolver The ambiguity resolver to use by this method delegator.
* @param assigner The assigner to be supplied by this method delegator.
* @param methodContainer A method container to query for methods to be considered for delegation.
*/
protected MethodDelegation(ImplementationDelegate implementationDelegate,
List> parameterBinders,
TargetMethodAnnotationDrivenBinder.DefaultsProvider defaultsProvider,
TargetMethodAnnotationDrivenBinder.TerminationHandler terminationHandler,
MethodDelegationBinder.AmbiguityResolver ambiguityResolver,
Assigner assigner,
MethodContainer methodContainer) {
this.implementationDelegate = implementationDelegate;
this.parameterBinders = parameterBinders;
this.defaultsProvider = defaultsProvider;
this.terminationHandler = terminationHandler;
this.ambiguityResolver = ambiguityResolver;
this.assigner = assigner;
this.methodContainer = methodContainer;
}
/**
* Creates an implementation where only {@code static} methods of the given type are considered as binding targets.
*
* @param type The type containing the {@code static} methods for binding.
* @return A method delegation implementation to the given {@code static} methods.
*/
public static MethodDelegation to(Class type) {
return to(new TypeDescription.ForLoadedType(type));
}
/**
* Creates an implementation where only {@code static} methods of the given type are considered as binding targets.
*
* @param typeDescription The type containing the {@code static} methods for binding.
* @return A method delegation implementation to the given {@code static} methods.
*/
public static MethodDelegation to(TypeDescription typeDescription) {
if (typeDescription.isArray()) {
throw new IllegalArgumentException("Cannot delegate to array " + typeDescription);
} else if (typeDescription.isPrimitive()) {
throw new IllegalArgumentException("Cannot delegate to primitive " + typeDescription);
}
return new MethodDelegation(ImplementationDelegate.ForStaticMethod.INSTANCE,
TargetMethodAnnotationDrivenBinder.ParameterBinder.DEFAULTS,
Argument.NextUnboundAsDefaultsProvider.INSTANCE,
TargetMethodAnnotationDrivenBinder.TerminationHandler.Returning.INSTANCE,
MethodDelegationBinder.AmbiguityResolver.DEFAULT,
Assigner.DEFAULT,
MethodContainer.ForExplicitMethods.ofStatic(typeDescription));
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @return A method delegation implementation to the given instance methods.
*/
public static MethodDelegation to(Object delegate) {
return to(delegate, MethodGraph.Compiler.DEFAULT);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param methodGraphCompiler The method graph compiler to be used for locating methods to delegate to.
* @return A method delegation implementation to the given instance methods.
*/
public static MethodDelegation to(Object delegate, MethodGraph.Compiler methodGraphCompiler) {
return to(delegate, delegate.getClass(), methodGraphCompiler);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param fieldName The name of the field for storing the delegate instance.
* @return A method delegation implementation to the given {@code static} methods.
*/
public static MethodDelegation to(Object delegate, String fieldName) {
return to(delegate, fieldName, MethodGraph.Compiler.DEFAULT);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param fieldName The name of the field for storing the delegate instance.
* @param methodGraphCompiler The method graph compiler to be used for locating methods to delegate to.
* @return A method delegation implementation to the given {@code static} methods.
*/
public static MethodDelegation to(Object delegate, String fieldName, MethodGraph.Compiler methodGraphCompiler) {
return to(delegate, delegate.getClass(), fieldName, methodGraphCompiler);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param type The type as which the delegate is treated for resolving its methods.
* @return A method delegation implementation to the given instance methods.
*/
public static MethodDelegation to(Object delegate, Type type) {
return to(delegate, type, MethodGraph.Compiler.DEFAULT);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param type The type as which the delegate is treated for resolving its methods.
* @param methodGraphCompiler The method graph compiler to be used for locating methods to delegate to.
* @return A method delegation implementation to the given instance methods.
*/
public static MethodDelegation to(Object delegate, Type type, MethodGraph.Compiler methodGraphCompiler) {
return to(delegate,
type,
String.format("%s$%d", ImplementationDelegate.ForStaticField.PREFIX, Math.abs(delegate.hashCode() % Integer.MAX_VALUE)),
methodGraphCompiler);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param type The type as which the delegate is treated for resolving its methods.
* @param fieldName The name of the field for storing the delegate instance.
* @return A method delegation implementation to the given {@code static} methods.
*/
public static MethodDelegation to(Object delegate, Type type, String fieldName) {
return to(delegate, type, fieldName, MethodGraph.Compiler.DEFAULT);
}
/**
* Creates an implementation where only instance methods of the given object are considered as binding targets.
* This method will never bind to constructors but will consider methods that are defined in super types. Note
* that this includes methods that were defined by the {@link java.lang.Object} class. You can narrow this default
* selection by explicitly selecting methods with calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* @param delegate A delegate instance which will be injected by a
* {@link com.fitbur.bytebuddy.implementation.LoadedTypeInitializer}. All intercepted method calls are
* then delegated to this instance.
* @param type The type as which the delegate is treated for resolving its methods.
* @param fieldName The name of the field for storing the delegate instance.
* @param methodGraphCompiler The method graph compiler to be used for locating methods to delegate to.
* @return A method delegation implementation to the given {@code static} methods.
*/
public static MethodDelegation to(Object delegate, Type type, String fieldName, MethodGraph.Compiler methodGraphCompiler) {
TypeDescription.Generic typeDescription = TypeDefinition.Sort.describe(type);
if (!typeDescription.asErasure().isInstance(delegate)) {
throw new IllegalArgumentException(delegate + " is not an instance of " + type);
}
return new MethodDelegation(new ImplementationDelegate.ForStaticField(delegate, fieldName),
TargetMethodAnnotationDrivenBinder.ParameterBinder.DEFAULTS,
Argument.NextUnboundAsDefaultsProvider.INSTANCE,
TargetMethodAnnotationDrivenBinder.TerminationHandler.Returning.INSTANCE,
MethodDelegationBinder.AmbiguityResolver.DEFAULT,
Assigner.DEFAULT,
new MethodContainer.ForVirtualMethods(methodGraphCompiler, typeDescription));
}
/**
* Creates an implementation where method calls are delegated to an instance that is manually stored in a field
* {@code fieldName} that is defined for the instrumented type. The field belongs to any instance of the instrumented
* type and must be set manually by the user of the instrumented class. Note that this prevents interception of
* method calls within the constructor of the instrumented class which will instead result in a
* {@link java.lang.NullPointerException}. Note that this includes methods that were defined by the
* {@link java.lang.Object} class. You can narrow this default selection by explicitly selecting methods with
* calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* The field is typically accessed by reflection or by defining an accessor on the instrumented type.
*
* @param type The type of the delegate and the field.
* @param fieldName The name of the field.
* @return A method delegation that intercepts method calls by delegating to method calls on the given instance.
*/
public static MethodDelegation toInstanceField(Class type, String fieldName) {
return toInstanceField(new TypeDescription.ForLoadedType(type), fieldName);
}
/**
* Creates an implementation where method calls are delegated to an instance that is manually stored in a field
* {@code fieldName} that is defined for the instrumented type. The field belongs to any instance of the instrumented
* type and must be set manually by the user of the instrumented class. Note that this prevents interception of
* method calls within the constructor of the instrumented class which will instead result in a
* {@link java.lang.NullPointerException}. Note that this includes methods that were defined by the
* {@link java.lang.Object} class. You can narrow this default selection by explicitly selecting methods with
* calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* The field is typically accessed by reflection or by defining an accessor on the instrumented type.
*
* @param typeDescription The type of the delegate and the field.
* @param fieldName The name of the field.
* @return A method delegation that intercepts method calls by delegating to method calls on the given instance.
*/
public static MethodDelegation toInstanceField(TypeDescription typeDescription, String fieldName) {
return toInstanceField(typeDescription, fieldName, MethodGraph.Compiler.DEFAULT);
}
/**
* Creates an implementation where method calls are delegated to an instance that is manually stored in a field
* {@code fieldName} that is defined for the instrumented type. The field belongs to any instance of the instrumented
* type and must be set manually by the user of the instrumented class. Note that this prevents interception of
* method calls within the constructor of the instrumented class which will instead result in a
* {@link java.lang.NullPointerException}. Note that this includes methods that were defined by the
* {@link java.lang.Object} class. You can narrow this default selection by explicitly selecting methods with
* calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to Foo where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* The field is typically accessed by reflection or by defining an accessor on the instrumented type.
*
* @param type The type of the delegate and the field.
* @param fieldName The name of the field.
* @param methodGraphCompiler The method graph compiler to be used for locating methods to delegate to.
* @return A method delegation that intercepts method calls by delegating to method calls on the given instance.
*/
public static MethodDelegation toInstanceField(Class type, String fieldName, MethodGraph.Compiler methodGraphCompiler) {
return toInstanceField(new TypeDescription.ForLoadedType(type), fieldName, methodGraphCompiler);
}
/**
* Creates an implementation where method calls are delegated to an instance that is manually stored in a field
* {@code fieldName} that is defined for the instrumented type. The field belongs to any instance of the instrumented
* type and must be set manually by the user of the instrumented class. Note that this prevents interception of
* method calls within the constructor of the instrumented class which will instead result in a
* {@link java.lang.NullPointerException}. Note that this includes methods that were defined by the
* {@link java.lang.Object} class. You can narrow this default selection by explicitly selecting methods with
* calling the
* {@link com.fitbur.bytebuddy.implementation.MethodDelegation#filter(com.fitbur.bytebuddy.matcher.ElementMatcher)}
* method on the returned method delegation as for example:
* MethodDelegation.to(new Foo()).filter(MethodMatchers.not(isDeclaredBy(Object.class)));
* which will result in a delegation to {@code Foo} where no methods of {@link java.lang.Object} are considered
* for delegation.
*
* The field is typically accessed by reflection or by defining an accessor on the instrumented type.
*
* @param typeDefinition The type of the delegate and the field.
* @param fieldName The name of the field.
* @param methodGraphCompiler The method graph compiler to be used for locating methods to delegate to.
* @return A method delegation that intercepts method calls by delegating to method calls on the given instance.
*/
public static MethodDelegation toInstanceField(TypeDefinition typeDefinition, String fieldName, MethodGraph.Compiler methodGraphCompiler) {
return new MethodDelegation(new ImplementationDelegate.ForInstanceField(typeDefinition.asGenericType(), fieldName),
TargetMethodAnnotationDrivenBinder.ParameterBinder.DEFAULTS,
Argument.NextUnboundAsDefaultsProvider.INSTANCE,
TargetMethodAnnotationDrivenBinder.TerminationHandler.Returning.INSTANCE,
MethodDelegationBinder.AmbiguityResolver.DEFAULT,
Assigner.DEFAULT,
new MethodContainer.ForVirtualMethods(methodGraphCompiler, typeDefinition.asGenericType()));
}
/**
* Creates an implementation where method calls are delegated to constructor calls on the given type. As a result,
* the return values of all instrumented methods must be assignable to
*
* @param type The type that should be constructed by the instrumented methods.
* @return An implementation that creates instances of the given type as its result.
*/
public static MethodDelegation toConstructor(Class type) {
return toConstructor(new TypeDescription.ForLoadedType(type));
}
/**
* Creates an implementation where method calls are delegated to constructor calls on the given type. As a result,
* the return values of all instrumented methods must be assignable to
*
* @param typeDescription The type that should be constructed by the instrumented methods.
* @return An implementation that creates instances of the given type as its result.
*/
public static MethodDelegation toConstructor(TypeDescription typeDescription) {
return new MethodDelegation(new ImplementationDelegate.ForConstruction(typeDescription),
TargetMethodAnnotationDrivenBinder.ParameterBinder.DEFAULTS,
Argument.NextUnboundAsDefaultsProvider.INSTANCE,
TargetMethodAnnotationDrivenBinder.TerminationHandler.Returning.INSTANCE,
MethodDelegationBinder.AmbiguityResolver.DEFAULT,
Assigner.DEFAULT,
MethodContainer.ForExplicitMethods.ofConstructors(typeDescription));
}
/**
* Defines an parameter binder to be appended to the already defined parameter binders.
*
* @param parameterBinder The parameter binder to append to the already defined parameter binders.
* @return A method delegation implementation that makes use of the given parameter binder.
*/
public MethodDelegation appendParameterBinder(TargetMethodAnnotationDrivenBinder.ParameterBinder parameterBinder) {
return new MethodDelegation(implementationDelegate,
CompoundList.of(parameterBinders, parameterBinder),
defaultsProvider,
terminationHandler,
ambiguityResolver,
assigner,
methodContainer);
}
/**
* Defines a number of parameter binders to be appended to be used by this method delegation.
*
* @param parameterBinder The parameter binders to use by this parameter binders.
* @return A method delegation implementation that makes use of the given parameter binders.
*/
public MethodDelegation defineParameterBinder(TargetMethodAnnotationDrivenBinder.ParameterBinder... parameterBinder) {
return new MethodDelegation(implementationDelegate,
Arrays.asList(parameterBinder),
defaultsProvider,
terminationHandler,
ambiguityResolver,
assigner,
methodContainer);
}
/**
* A provider for annotation instances on values that are not explicitly annotated.
*
* @param defaultsProvider The defaults provider to use.
* @return A method delegation implementation that makes use of the given defaults provider.
*/
public MethodDelegation withDefaultsProvider(TargetMethodAnnotationDrivenBinder.DefaultsProvider defaultsProvider) {
return new MethodDelegation(implementationDelegate,
parameterBinders,
defaultsProvider,
terminationHandler,
ambiguityResolver,
assigner,
methodContainer);
}
/**
* Defines an ambiguity resolver to be appended to the already defined ambiguity resolver for resolving binding conflicts.
*
* @param ambiguityResolver The ambiguity resolver to append to the already defined ambiguity resolvers.
* @return A method delegation implementation that makes use of the given ambiguity resolver.
*/
public MethodDelegation appendAmbiguityResolver(MethodDelegationBinder.AmbiguityResolver ambiguityResolver) {
return defineAmbiguityResolver(new MethodDelegationBinder.AmbiguityResolver.Chain(this.ambiguityResolver, ambiguityResolver));
}
/**
* Defines an ambiguity resolver to be used for resolving binding conflicts.
*
* @param ambiguityResolver The ambiguity resolver to use exclusively.
* @return A method delegation implementation that makes use of the given ambiguity resolver.
*/
public MethodDelegation defineAmbiguityResolver(MethodDelegationBinder.AmbiguityResolver... ambiguityResolver) {
return new MethodDelegation(implementationDelegate,
parameterBinders,
defaultsProvider,
terminationHandler,
new MethodDelegationBinder.AmbiguityResolver.Chain(ambiguityResolver),
assigner,
methodContainer);
}
/**
* Applies an assigner to the method delegation that is used for assigning method return and parameter types.
*
* @param assigner The assigner to apply.
* @return A method delegation implementation that makes use of the given designer.
*/
public MethodDelegation withAssigner(Assigner assigner) {
return new MethodDelegation(implementationDelegate,
parameterBinders,
defaultsProvider,
terminationHandler,
ambiguityResolver,
assigner,
methodContainer);
}
/**
* Applies a filter to target methods that are eligible for delegation.
*
* @param methodMatcher A filter where only methods that match the filter are considered for delegation.
* @return A method delegation with the filter applied.
*/
public MethodDelegation filter(ElementMatcher methodMatcher) {
return new MethodDelegation(implementationDelegate,
parameterBinders,
defaultsProvider,
terminationHandler,
ambiguityResolver,
assigner,
methodContainer.filter(methodMatcher));
}
@Override
public Implementation andThen(Implementation implementation) {
return new Compound(new MethodDelegation(implementationDelegate,
parameterBinders,
defaultsProvider,
TargetMethodAnnotationDrivenBinder.TerminationHandler.Dropping.INSTANCE,
ambiguityResolver,
assigner,
methodContainer), implementation);
}
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return implementationDelegate.prepare(instrumentedType);
}
@Override
public ByteCodeAppender appender(Target implementationTarget) {
return new Appender(implementationDelegate.getPreparingStackAssignment(implementationTarget.getInstrumentedType()),
implementationTarget,
methodContainer.resolve(implementationTarget.getInstrumentedType()),
new MethodDelegationBinder.Processor(new TargetMethodAnnotationDrivenBinder(
parameterBinders,
defaultsProvider,
terminationHandler,
assigner,
implementationDelegate.getMethodInvoker(implementationTarget.getInstrumentedType())
), ambiguityResolver)
);
}
@Override
public boolean equals(Object other) {
if (this == other) return true;
if (other == null || getClass() != other.getClass()) return false;
MethodDelegation that = (MethodDelegation) other;
return ambiguityResolver.equals(that.ambiguityResolver)
&& assigner.equals(that.assigner)
&& defaultsProvider.equals(that.defaultsProvider)
&& terminationHandler.equals(that.terminationHandler)
&& implementationDelegate.equals(that.implementationDelegate)
&& methodContainer.equals(that.methodContainer)
&& parameterBinders.equals(that.parameterBinders);
}
@Override
public int hashCode() {
int result = implementationDelegate.hashCode();
result = 31 * result + parameterBinders.hashCode();
result = 31 * result + defaultsProvider.hashCode();
result = 31 * result + terminationHandler.hashCode();
result = 31 * result + ambiguityResolver.hashCode();
result = 31 * result + assigner.hashCode();
result = 31 * result + methodContainer.hashCode();
return result;
}
@Override
public String toString() {
return "MethodDelegation{" +
"implementationDelegate=" + implementationDelegate +
", parameterBinders=" + parameterBinders +
", defaultsProvider=" + defaultsProvider +
", terminationHandler=" + terminationHandler +
", ambiguityResolver=" + ambiguityResolver +
", assigner=" + assigner +
", methodContainer=" + methodContainer +
'}';
}
/**
* An implementation delegate is responsible for executing the actual method delegation.
*/
protected interface ImplementationDelegate {
/**
* Prepares the instrumented type.
*
* @param instrumentedType The instrumented type to be prepared.
* @return The instrumented type after it was prepared.
*/
InstrumentedType prepare(InstrumentedType instrumentedType);
/**
* Returns the stack manipulation responsible for preparing the instance representing the implementation.
*
* @param instrumentedType A description of the instrumented type to which the implementation is applied.
* @return A stack manipulation representing the preparation.
*/
StackManipulation getPreparingStackAssignment(TypeDescription instrumentedType);
/**
* Returns the method invoker responsible for invoking the delegation method.
*
* @param instrumentedType The instrumented type to which the implementation is applied.
* @return A method invoker responsible for invoking the delegation method.
*/
MethodDelegationBinder.MethodInvoker getMethodInvoker(TypeDescription instrumentedType);
/**
* An implementation applied to a static method.
*/
enum ForStaticMethod implements ImplementationDelegate {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType;
}
@Override
public StackManipulation getPreparingStackAssignment(TypeDescription instrumentedType) {
return StackManipulation.Trivial.INSTANCE;
}
@Override
public MethodDelegationBinder.MethodInvoker getMethodInvoker(TypeDescription instrumentedType) {
return MethodDelegationBinder.MethodInvoker.Simple.INSTANCE;
}
@Override
public String toString() {
return "MethodDelegation.ImplementationDelegate.ForStaticMethod." + name();
}
}
/**
* An implementation applied on a static field.
*/
class ForStaticField implements ImplementationDelegate {
/**
* The name prefix for the {@code static} field that is containing the delegation target.
*/
protected static final String PREFIX = "delegate";
/**
* The name of the field that is containing the delegation target.
*/
private final String fieldName;
/**
* The delegation target.
*/
private final Object delegate;
/**
* Creates a new implementation for delegating to an instance that is stored in a {@code static} field.
*
* @param delegate The actual delegation target.
* @param fieldName The name of the field for storing the delegate instance.
*/
public ForStaticField(Object delegate, String fieldName) {
this.delegate = delegate;
this.fieldName = fieldName;
}
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType
.withField(new FieldDescription.Token(fieldName,
Opcodes.ACC_SYNTHETIC | Opcodes.ACC_STATIC | Opcodes.ACC_PUBLIC,
new TypeDescription.Generic.OfNonGenericType.ForLoadedType(delegate.getClass())))
.withInitializer(new LoadedTypeInitializer.ForStaticField(fieldName, delegate));
}
@Override
public StackManipulation getPreparingStackAssignment(TypeDescription instrumentedType) {
return FieldAccess.forField(instrumentedType.getDeclaredFields().filter((named(fieldName))).getOnly()).getter();
}
@Override
public MethodDelegationBinder.MethodInvoker getMethodInvoker(TypeDescription instrumentedType) {
return new MethodDelegationBinder.MethodInvoker.Virtual(new TypeDescription.ForLoadedType(delegate.getClass()));
}
@Override
public boolean equals(Object other) {
return this == other || !(other == null || getClass() != other.getClass())
&& delegate.equals(((ForStaticField) other).delegate)
&& fieldName.equals(((ForStaticField) other).fieldName);
}
@Override
public int hashCode() {
return 31 * fieldName.hashCode() + delegate.hashCode();
}
@Override
public String toString() {
return "MethodDelegation.ImplementationDelegate.ForStaticField{" +
"fieldName='" + fieldName + '\'' +
", delegate=" + delegate +
'}';
}
}
/**
* An implementation applied on an instance field.
*/
class ForInstanceField implements ImplementationDelegate {
/**
* The name of the instance field that is containing the target of the method delegation.
*/
private final String fieldName;
/**
* The type of the method delegation target.
*/
private final TypeDescription.Generic fieldType;
/**
* Creates a new instance field implementation delegate.
*
* @param fieldType A description of the type that is the target of the implementation and thus also the
* field type.
* @param fieldName The name of the field.
*/
public ForInstanceField(TypeDescription.Generic fieldType, String fieldName) {
this.fieldType = fieldType;
this.fieldName = fieldName;
}
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType.withField(new FieldDescription.Token(fieldName, Opcodes.ACC_PUBLIC, fieldType));
}
@Override
public StackManipulation getPreparingStackAssignment(TypeDescription instrumentedType) {
return new StackManipulation.Compound(MethodVariableAccess.REFERENCE.loadOffset(0),
FieldAccess.forField(instrumentedType.getDeclaredFields().filter((named(fieldName))).getOnly()).getter());
}
@Override
public MethodDelegationBinder.MethodInvoker getMethodInvoker(TypeDescription instrumentedType) {
return new MethodDelegationBinder.MethodInvoker.Virtual(fieldType.asErasure());
}
@Override
public boolean equals(Object other) {
return this == other || !(other == null || getClass() != other.getClass())
&& fieldName.equals(((ForInstanceField) other).fieldName)
&& fieldType.equals(((ForInstanceField) other).fieldType);
}
@Override
public int hashCode() {
return 31 * fieldName.hashCode() + fieldType.hashCode();
}
@Override
public String toString() {
return "MethodDelegation.ImplementationDelegate.ForInstanceField{" +
"fieldName='" + fieldName + '\'' +
", fieldType=" + fieldType +
'}';
}
}
/**
* An implementation that creates new instances of a given type.
*/
class ForConstruction implements ImplementationDelegate {
/**
* The type that is to be constructed.
*/
private final TypeDescription typeDescription;
/**
* Creates a new constructor implementation.
*
* @param typeDescription The type to be constructed.
*/
public ForConstruction(TypeDescription typeDescription) {
this.typeDescription = typeDescription;
}
@Override
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType;
}
@Override
public StackManipulation getPreparingStackAssignment(TypeDescription instrumentedType) {
return new StackManipulation.Compound(
TypeCreation.of(typeDescription),
Duplication.SINGLE);
}
@Override
public MethodDelegationBinder.MethodInvoker getMethodInvoker(TypeDescription instrumentedType) {
return MethodDelegationBinder.MethodInvoker.Simple.INSTANCE;
}
@Override
public boolean equals(Object other) {
return this == other || !(other == null || getClass() != other.getClass())
&& typeDescription.equals(((ForConstruction) other).typeDescription);
}
@Override
public int hashCode() {
return typeDescription.hashCode();
}
@Override
public String toString() {
return "MethodDelegation.ImplementationDelegate.ForConstruction{" +
"typeDescription=" + typeDescription +
'}';
}
}
}
/**
* A method container collects methods that are considered as a target for delegation.
*/
protected interface MethodContainer {
/**
* Appends a filter that is applied to the methods that this container represents.
*
* @param matcher The matcher that is to be applied for filtering methods.
* @return A method container with the supplied filter applied.
*/
MethodContainer filter(ElementMatcher matcher);
/**
* Resolves this method container to extract a list of methods to be considered for interception.
*
* @param instrumentedType The instrumented type.
* @return A list of methods to be considered as delegation target.
*/
MethodList resolve(TypeDescription instrumentedType);
/**
* A method container for an explicit list of methods.
*/
class ForExplicitMethods implements MethodContainer {
/**
* The methods to be considered.
*/
private final MethodList methodList;
/**
* Creates a new explicit method container.
*
* @param methodList The methods to be considered.
*/
protected ForExplicitMethods(MethodList methodList) {
this.methodList = methodList;
}
/**
* Creates a container for all static methods of the given type description.
*
* @param typeDescription The type description of which all static methods should be considered.
* @return An appropriate method container.
*/
protected static MethodContainer ofStatic(TypeDescription typeDescription) {
return new ForExplicitMethods(typeDescription.getDeclaredMethods().filter(isStatic()));
}
/**
* Creates a container for all constructors of the given type description.
*
* @param typeDescription The type description of which all constructors should be considered.
* @return An appropriate method container.
*/
protected static MethodContainer ofConstructors(TypeDescription typeDescription) {
return new ForExplicitMethods(typeDescription.getDeclaredMethods().filter(isConstructor()));
}
@Override
public MethodContainer filter(ElementMatcher matcher) {
return new ForExplicitMethods(methodList.filter(matcher));
}
@Override
public MethodList resolve(TypeDescription instrumentedType) {
return methodList.filter(isVisibleTo(instrumentedType));
}
@Override
public boolean equals(Object other) {
return this == other || !(other == null || getClass() != other.getClass())
&& methodList.equals(((ForExplicitMethods) other).methodList);
}
@Override
public int hashCode() {
return methodList.hashCode();
}
@Override
public String toString() {
return "MethodDelegation.MethodContainer.ForExplicitMethods{" +
"methodList=" + methodList +
'}';
}
}
/**
* A method container for which all virtual methods of a given type should be considered.
*/
class ForVirtualMethods implements MethodContainer {
/**
* The method graph compiler to use.
*/
private final MethodGraph.Compiler methodGraphCompiler;
/**
* The target type for which the virtual methods should be extracted.
*/
private final TypeDescription.Generic targetType;
/**
* A matcher representing a filter to be applied to the extracted methods.
*/
private final ElementMatcher matcher;
/**
* Creates a new method container for virtual method extraction.
*
* @param methodGraphCompiler The method graph compiler to use.
* @param targetType The target type for which the virtual methods should be extracted.
*/
protected ForVirtualMethods(MethodGraph.Compiler methodGraphCompiler, TypeDescription.Generic targetType) {
this(methodGraphCompiler, targetType, any());
}
/**
* Creates a new method container for virtual method extraction.
*
* @param methodGraphCompiler The method graph compiler to use.
* @param targetType The target type for which the virtual methods should be extracted.
* @param matcher A matcher representing a filter to be applied to the extracted methods.
*/
private ForVirtualMethods(MethodGraph.Compiler methodGraphCompiler,
TypeDescription.Generic targetType,
ElementMatcher matcher) {
this.methodGraphCompiler = methodGraphCompiler;
this.targetType = targetType;
this.matcher = matcher;
}
@Override
public MethodContainer filter(ElementMatcher matcher) {
return new ForVirtualMethods(methodGraphCompiler,
targetType,
new ElementMatcher.Junction.Conjunction(this.matcher, matcher));
}
@Override
public MethodList resolve(TypeDescription instrumentedType) {
if (!targetType.asErasure().isVisibleTo(instrumentedType)) {
throw new IllegalStateException(instrumentedType + " cannot access " + targetType);
}
return methodGraphCompiler.compile(targetType, instrumentedType).listNodes().asMethodList().filter(matcher);
}
@Override
public boolean equals(Object other) {
if (this == other) return true;
if (other == null || getClass() != other.getClass()) return false;
ForVirtualMethods that = (ForVirtualMethods) other;
return methodGraphCompiler.equals(that.methodGraphCompiler)
&& targetType.equals(that.targetType)
&& matcher.equals(that.matcher);
}
@Override
public int hashCode() {
int result = methodGraphCompiler.hashCode();
result = 31 * result + targetType.hashCode();
result = 31 * result + matcher.hashCode();
return result;
}
@Override
public String toString() {
return "MethodDelegation.MethodContainer.ForVirtualMethods{" +
"methodGraphCompiler=" + methodGraphCompiler +
", targetType=" + targetType +
", matcher=" + matcher +
'}';
}
}
}
/**
* The appender for implementing a {@link com.fitbur.bytebuddy.implementation.MethodDelegation}.
*/
protected static class Appender implements ByteCodeAppender {
/**
* The stack manipulation that is responsible for loading a potential target instance onto the stack
* on which the target method is invoked.
*/
private final StackManipulation preparingStackAssignment;
/**
* The implementation target of this implementation.
*/
private final Target implementationTarget;
/**
* The method candidates to consider for delegating the invocation to.
*/
private final MethodList targetCandidates;
/**
* The method delegation binder processor which is responsible for implementing the method delegation.
*/
private final MethodDelegationBinder.Processor processor;
/**
* Creates a new appender.
*
* @param preparingStackAssignment The stack manipulation that is responsible for loading a potential target
* instance onto the stack on which the target method is invoked.
* @param implementationTarget The implementation target of this implementation.
* @param targetCandidates The method candidates to consider for delegating the invocation to.
* @param processor The method delegation binder processor which is responsible for implementing
* the method delegation.
*/
protected Appender(StackManipulation preparingStackAssignment,
Target implementationTarget,
MethodList targetCandidates,
MethodDelegationBinder.Processor processor) {
this.preparingStackAssignment = preparingStackAssignment;
this.implementationTarget = implementationTarget;
this.targetCandidates = targetCandidates;
this.processor = processor;
}
@Override
public Size apply(MethodVisitor methodVisitor, Context implementationContext, MethodDescription instrumentedMethod) {
StackManipulation.Size stackSize = new StackManipulation.Compound(
preparingStackAssignment,
processor.process(implementationTarget, instrumentedMethod, targetCandidates)
).apply(methodVisitor, implementationContext);
return new Size(stackSize.getMaximalSize(), instrumentedMethod.getStackSize());
}
@Override
public boolean equals(Object other) {
if (this == other) return true;
if (other == null || getClass() != other.getClass()) return false;
Appender that = (Appender) other;
return implementationTarget.equals(that.implementationTarget)
&& preparingStackAssignment.equals(that.preparingStackAssignment)
&& processor.equals(that.processor)
&& targetCandidates.equals(that.targetCandidates);
}
@Override
public int hashCode() {
int result = preparingStackAssignment.hashCode();
result = 31 * result + implementationTarget.hashCode();
result = 31 * result + targetCandidates.hashCode();
result = 31 * result + processor.hashCode();
return result;
}
@Override
public String toString() {
return "MethodDelegation.Appender{" +
"preparingStackAssignment=" + preparingStackAssignment +
", implementationTarget=" + implementationTarget +
", targetCandidates=" + targetCandidates +
", processor=" + processor +
'}';
}
}
}