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package org.testifyproject.bytebuddy.implementation.bind.annotation;
import lombok.EqualsAndHashCode;
import org.testifyproject.bytebuddy.description.annotation.AnnotationDescription;
import org.testifyproject.bytebuddy.description.method.MethodDescription;
import org.testifyproject.bytebuddy.description.method.ParameterDescription;
import org.testifyproject.bytebuddy.description.type.TypeDescription;
import org.testifyproject.bytebuddy.implementation.Implementation;
import org.testifyproject.bytebuddy.implementation.MethodAccessorFactory;
import org.testifyproject.bytebuddy.implementation.bind.MethodDelegationBinder;
import org.testifyproject.bytebuddy.implementation.bytecode.StackManipulation;
import org.testifyproject.bytebuddy.implementation.bytecode.assign.Assigner;
import org.testifyproject.bytebuddy.implementation.bytecode.constant.MethodConstant;
import org.testifyproject.bytebuddy.implementation.bytecode.constant.NullConstant;
import org.testifyproject.bytebuddy.implementation.bytecode.member.FieldAccess;
import org.testifyproject.bytebuddy.jar.asm.MethodVisitor;
import java.lang.annotation.*;
import java.lang.reflect.Method;
/**
* A parameter with this annotation is assigned an instance of {@link Method} which invokes the super implementation of this method.
* If such a method is not available, this annotation causes that this delegation target cannot be bound unless {@link SuperMethod#nullIfImpossible()}
* is set to {@code true}. The method is declared as {@code public} and is invokable unless the instrumented type itself is not visible. Note that
* requesting such a method exposes the super method to reflection.
*
* @see org.testifyproject.bytebuddy.implementation.MethodDelegation
* @see org.testifyproject.bytebuddy.implementation.bind.annotation.TargetMethodAnnotationDrivenBinder
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PARAMETER)
public @interface SuperMethod {
/**
* Indicates if the instance assigned to this parameter should be stored in a static field for reuse.
*
* @return {@code true} if this method instance should be cached.
*/
boolean cached() default true;
/**
* Indicates that the assigned method should attemt the invocation of an unambiguous default method if no super method is available.
*
* @return {@code true} if a default method should be invoked if it is not ambiguous and no super class method is available.
*/
boolean fallbackToDefault() default true;
/**
* Indicates that {@code null} should be assigned to this parameter if no super method is invokable.
*
* @return {@code true} if {@code null} should be assigned if no valid method can be assigned.
*/
boolean nullIfImpossible() default false;
/**
* A binder for the {@link SuperMethod} annotation.
*/
enum Binder implements TargetMethodAnnotationDrivenBinder.ParameterBinder {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public Class getHandledType() {
return SuperMethod.class;
}
@Override
public MethodDelegationBinder.ParameterBinding bind(final AnnotationDescription.Loadable annotation,
MethodDescription source,
ParameterDescription target,
Implementation.Target implementationTarget,
Assigner assigner,
Assigner.Typing typing) {
if (!target.getType().asErasure().isAssignableFrom(Method.class)) {
throw new IllegalStateException("Cannot assign Method type to " + target);
} else if (source.isMethod()) {
Implementation.SpecialMethodInvocation specialMethodInvocation = annotation.loadSilent().fallbackToDefault()
? implementationTarget.invokeDominant(source.asSignatureToken())
: implementationTarget.invokeSuper(source.asSignatureToken());
if (specialMethodInvocation.isValid()) {
return new MethodDelegationBinder.ParameterBinding.Anonymous(new DelegationMethod(specialMethodInvocation, annotation.loadSilent().cached()));
} else if (annotation.loadSilent().nullIfImpossible()) {
return new MethodDelegationBinder.ParameterBinding.Anonymous(NullConstant.INSTANCE);
} else {
return MethodDelegationBinder.ParameterBinding.Illegal.INSTANCE;
}
} else if (annotation.loadSilent().nullIfImpossible()) {
return new MethodDelegationBinder.ParameterBinding.Anonymous(NullConstant.INSTANCE);
} else {
return MethodDelegationBinder.ParameterBinding.Illegal.INSTANCE;
}
}
/**
* Loads the delegation method constant onto the stack.
*/
@EqualsAndHashCode
protected static class DelegationMethod implements StackManipulation {
/**
* The special method invocation that represents the super method call.
*/
private final Implementation.SpecialMethodInvocation specialMethodInvocation;
/**
* {@code true} if the method constant should be cached.
*/
private final boolean cached;
/**
* Creates a new delegation method.
*
* @param specialMethodInvocation The special method invocation that represents the super method call.
* @param cached {@code true} if the method constant should be cached.
*/
protected DelegationMethod(Implementation.SpecialMethodInvocation specialMethodInvocation, boolean cached) {
this.specialMethodInvocation = specialMethodInvocation;
this.cached = cached;
}
@Override
public boolean isValid() {
return specialMethodInvocation.isValid();
}
@Override
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
StackManipulation stackManipulation = MethodConstant.forMethod(implementationContext.registerAccessorFor(specialMethodInvocation,
MethodAccessorFactory.AccessType.PUBLIC));
return (cached
? FieldAccess.forField(implementationContext.cache(stackManipulation, new TypeDescription.ForLoadedType(Method.class))).read()
: stackManipulation).apply(methodVisitor, implementationContext);
}
}
}
}