net.bytebuddy.implementation.bind.annotation.SuperCall Maven / Gradle / Ivy
/*
* Copyright 2014 - Present Rafael Winterhalter
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.bytebuddy.implementation.bind.annotation;
import net.bytebuddy.description.annotation.AnnotationDescription;
import net.bytebuddy.description.method.MethodDescription;
import net.bytebuddy.description.method.MethodList;
import net.bytebuddy.description.method.ParameterDescription;
import net.bytebuddy.description.type.TypeDescription;
import net.bytebuddy.implementation.Implementation;
import net.bytebuddy.implementation.auxiliary.MethodCallProxy;
import net.bytebuddy.implementation.bind.MethodDelegationBinder;
import net.bytebuddy.implementation.bytecode.StackManipulation;
import net.bytebuddy.implementation.bytecode.assign.Assigner;
import net.bytebuddy.implementation.bytecode.constant.NullConstant;
import java.lang.annotation.*;
import java.util.concurrent.Callable;
import static net.bytebuddy.matcher.ElementMatchers.named;
/**
* Parameters that are annotated with this annotation will be assigned a proxy for calling the instrumented method's
* {@code super} implementation.
*
* The proxy will both implement the {@link java.util.concurrent.Callable} and the {@link java.lang.Runnable} interfaces
* such that the annotated parameter must be assignable to any of those interfaces or be of the {@link java.lang.Object}
* type.
*
* @see net.bytebuddy.implementation.MethodDelegation
* @see net.bytebuddy.implementation.bind.annotation.TargetMethodAnnotationDrivenBinder
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PARAMETER)
public @interface SuperCall {
/**
* Determines if the generated proxy should be {@link java.io.Serializable}.
*
* @return {@code true} if the generated proxy should be {@link java.io.Serializable}.
*/
boolean serializableProxy() default false;
/**
* Determines if the injected proxy should invoke the default method to the intercepted method if a common
* super method invocation is not applicable. For this to be possible, the default method must not be ambiguous.
*
* @return {@code true} if the invocation should fall back to invoking the default method.
*/
boolean fallbackToDefault() default true;
/**
* Assigns {@code null} to the parameter if it is impossible to invoke the super method or a possible dominant default method, if permitted.
*
* @return {@code true} if a {@code null} constant should be assigned to this parameter in case that a legal binding is impossible.
*/
boolean nullIfImpossible() default false;
/**
* A binder for handling the
* {@link net.bytebuddy.implementation.bind.annotation.SuperCall}
* annotation.
*
* @see TargetMethodAnnotationDrivenBinder
*/
enum Binder implements TargetMethodAnnotationDrivenBinder.ParameterBinder {
/**
* The singleton instance.
*/
INSTANCE;
/**
* A description of the {@link SuperCall#serializableProxy()} method.
*/
private static final MethodDescription.InDefinedShape SERIALIZABLE_PROXY;
/**
* A description of the {@link SuperCall#fallbackToDefault()} method.
*/
private static final MethodDescription.InDefinedShape FALLBACK_TO_DEFAULT;
/**
* A description of the {@link SuperCall#nullIfImpossible()} method.
*/
private static final MethodDescription.InDefinedShape NULL_IF_IMPOSSIBLE;
/*
* Resolves annotation properties.
*/
static {
MethodList methods = TypeDescription.ForLoadedType.of(SuperCall.class).getDeclaredMethods();
SERIALIZABLE_PROXY = methods.filter(named("serializableProxy")).getOnly();
FALLBACK_TO_DEFAULT = methods.filter(named("fallbackToDefault")).getOnly();
NULL_IF_IMPOSSIBLE = methods.filter(named("nullIfImpossible")).getOnly();
}
/**
* {@inheritDoc}
*/
public Class getHandledType() {
return SuperCall.class;
}
/**
* {@inheritDoc}
*/
public MethodDelegationBinder.ParameterBinding bind(AnnotationDescription.Loadable annotation,
MethodDescription source,
ParameterDescription target,
Implementation.Target implementationTarget,
Assigner assigner,
Assigner.Typing typing) {
TypeDescription targetType = target.getType().asErasure();
if (!targetType.represents(Runnable.class) && !targetType.represents(Callable.class) && !targetType.represents(Object.class)) {
throw new IllegalStateException("A super method call proxy can only be assigned to Runnable or Callable types: " + target);
} else if (source.isConstructor()) {
return annotation.getValue(NULL_IF_IMPOSSIBLE).resolve(Boolean.class)
? new MethodDelegationBinder.ParameterBinding.Anonymous(NullConstant.INSTANCE)
: MethodDelegationBinder.ParameterBinding.Illegal.INSTANCE;
}
Implementation.SpecialMethodInvocation specialMethodInvocation = (annotation.getValue(FALLBACK_TO_DEFAULT).resolve(Boolean.class)
? implementationTarget.invokeDominant(source.asSignatureToken())
: implementationTarget.invokeSuper(source.asSignatureToken())).withCheckedCompatibilityTo(source.asTypeToken());
StackManipulation stackManipulation;
if (specialMethodInvocation.isValid()) {
stackManipulation = new MethodCallProxy.AssignableSignatureCall(specialMethodInvocation, annotation.getValue(SERIALIZABLE_PROXY).resolve(Boolean.class));
} else if (annotation.getValue(NULL_IF_IMPOSSIBLE).resolve(Boolean.class)) {
stackManipulation = NullConstant.INSTANCE;
} else {
return MethodDelegationBinder.ParameterBinding.Illegal.INSTANCE;
}
return new MethodDelegationBinder.ParameterBinding.Anonymous(stackManipulation);
}
}
}