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Byte Buddy is a Java library for creating Java classes at run time.
This artifact is a build of Byte Buddy with a remaining dependency onto ASM.
You should never depend on this module without repackaging Byte Buddy and ASM into your own namespace.
/*
* 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;
import net.bytebuddy.build.HashCodeAndEqualsPlugin;
import net.bytebuddy.description.method.MethodDescription;
import net.bytebuddy.dynamic.scaffold.InstrumentedType;
import net.bytebuddy.implementation.bytecode.ByteCodeAppender;
import net.bytebuddy.implementation.bytecode.Removal;
import net.bytebuddy.implementation.bytecode.StackManipulation;
import net.bytebuddy.implementation.bytecode.member.MethodReturn;
import net.bytebuddy.implementation.bytecode.member.MethodVariableAccess;
import org.objectweb.asm.MethodVisitor;
/**
* This implementation will create a new method which simply calls its super method. If no such method is defined,
* an exception will be thrown. Constructors are considered to have a super method if the direct super class defines
* a constructor with an identical signature. Default methods are invoked as such if they are non-ambiguous. Static
* methods can have a (pseudo) super method if a type that defines such a method is rebased. Rebased types can also
* shadow constructors or methods of an actual super class. Besides implementing constructors, this implementation
* is useful when a method of a super type is not supposed to be altered but should be equipped with additional
* annotations. Furthermore, this implementation allows to hard code a super method call to be performed after
* performing another {@link Implementation}.
*/
public enum SuperMethodCall implements Implementation.Composable {
/**
* The singleton instance.
*/
INSTANCE;
/**
* {@inheritDoc}
*/
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType;
}
/**
* {@inheritDoc}
*/
public ByteCodeAppender appender(Target implementationTarget) {
return new Appender(implementationTarget, Appender.TerminationHandler.RETURNING);
}
/**
* {@inheritDoc}
*/
public Implementation andThen(Implementation implementation) {
return new Compound(WithoutReturn.INSTANCE, implementation);
}
/**
* {@inheritDoc}
*/
public Composable andThen(Composable implementation) {
return new Compound.Composable(WithoutReturn.INSTANCE, implementation);
}
/**
* A super method invocation where the return value is dropped instead of returning from the method.
*/
protected enum WithoutReturn implements Implementation {
/**
* The singleton instance.
*/
INSTANCE;
/**
* {@inheritDoc}
*/
public InstrumentedType prepare(InstrumentedType instrumentedType) {
return instrumentedType;
}
/**
* {@inheritDoc}
*/
public ByteCodeAppender appender(Target implementationTarget) {
return new Appender(implementationTarget, Appender.TerminationHandler.DROPPING);
}
}
/**
* An appender for implementing a {@link net.bytebuddy.implementation.SuperMethodCall}.
*/
@HashCodeAndEqualsPlugin.Enhance
protected static class Appender implements ByteCodeAppender {
/**
* The target of the current implementation.
*/
private final Target implementationTarget;
/**
* The termination handler to apply after invoking the super method.
*/
private final TerminationHandler terminationHandler;
/**
* Creates a new appender.
*
* @param implementationTarget The implementation target of the current type creation.
* @param terminationHandler The termination handler to apply after invoking the super method.
*/
protected Appender(Target implementationTarget, TerminationHandler terminationHandler) {
this.implementationTarget = implementationTarget;
this.terminationHandler = terminationHandler;
}
/**
* {@inheritDoc}
*/
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext, MethodDescription instrumentedMethod) {
StackManipulation superMethodCall = implementationTarget
.invokeDominant(instrumentedMethod.asSignatureToken())
.withCheckedCompatibilityTo(instrumentedMethod.asTypeToken());
if (!superMethodCall.isValid()) {
throw new IllegalStateException("Cannot call super (or default) method for " + instrumentedMethod);
}
StackManipulation.Size size = new StackManipulation.Compound(
MethodVariableAccess.allArgumentsOf(instrumentedMethod).prependThisReference(),
superMethodCall,
terminationHandler.of(instrumentedMethod)
).apply(methodVisitor, implementationContext);
return new Size(size.getMaximalSize(), instrumentedMethod.getStackSize());
}
/**
* A handler that determines how to handle the method return value.
*/
protected enum TerminationHandler {
/**
* A termination handler that returns the value of the super method invocation.
*/
RETURNING {
@Override
protected StackManipulation of(MethodDescription methodDescription) {
return MethodReturn.of(methodDescription.getReturnType());
}
},
/**
* A termination handler that simply pops the value of the super method invocation off the stack.
*/
DROPPING {
@Override
protected StackManipulation of(MethodDescription methodDescription) {
return Removal.of(methodDescription.getReturnType());
}
};
/**
* Creates a stack manipulation that represents this handler's behavior.
*
* @param methodDescription The method for which this handler is supposed to create a stack
* manipulation for.
* @return The stack manipulation that implements this handler.
*/
protected abstract StackManipulation of(MethodDescription methodDescription);
}
}
}