net.bytebuddy.implementation.bytecode.constant.MethodConstant Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of byte-buddy Show documentation
Show all versions of byte-buddy Show documentation
Byte Buddy is a Java library for creating Java classes at run time.
This artifact is a build of Byte Buddy with all ASM dependencies repackaged into its own name space.
/*
* 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.bytecode.constant;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import net.bytebuddy.description.method.MethodDescription;
import net.bytebuddy.description.type.TypeDescription;
import net.bytebuddy.implementation.Implementation;
import net.bytebuddy.implementation.auxiliary.PrivilegedMemberLookupAction;
import net.bytebuddy.implementation.bytecode.Duplication;
import net.bytebuddy.implementation.bytecode.StackManipulation;
import net.bytebuddy.implementation.bytecode.TypeCreation;
import net.bytebuddy.implementation.bytecode.assign.TypeCasting;
import net.bytebuddy.implementation.bytecode.collection.ArrayFactory;
import net.bytebuddy.implementation.bytecode.member.FieldAccess;
import net.bytebuddy.implementation.bytecode.member.MethodInvocation;
import net.bytebuddy.utility.nullability.MaybeNull;
import net.bytebuddy.jar.asm.MethodVisitor;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.security.PrivilegedExceptionAction;
import java.util.ArrayList;
import java.util.List;
import static net.bytebuddy.matcher.ElementMatchers.isConstructor;
/**
* Represents the creation of a {@link java.lang.reflect.Method} value which can be created from a given
* set of constant pool values and can therefore be considered a constant in the broader meaning.
*/
public abstract class MethodConstant extends StackManipulation.AbstractBase {
/**
* The {@code java.security.AccessController#doPrivileged(PrivilegedExceptionAction)} method or {@code null} if
* this method is not available on the current VM.
*/
@MaybeNull
protected static final MethodDescription.InDefinedShape DO_PRIVILEGED = doPrivileged();
/**
* Resolves the {@code java.security.AccessController#doPrivileged} method if the security manager is supported
* on the current VM and if security manager support is not explicitly disabled.
*
* @return The {@code doPrivileged} method or {@code null}.
*/
@MaybeNull
@SuppressFBWarnings(value = "REC_CATCH_EXCEPTION", justification = "Exception should not be rethrown but trigger a fallback.")
private static MethodDescription.InDefinedShape doPrivileged() {
MethodDescription.InDefinedShape doPrivileged;
try {
doPrivileged = new MethodDescription.ForLoadedMethod(Class.forName("java.security.AccessController").getMethod("doPrivileged", PrivilegedExceptionAction.class));
try {
if (!Boolean.parseBoolean(System.getProperty("net.bytebuddy.securitymanager", "true"))) {
doPrivileged = null;
}
} catch (SecurityException ignored) {
/* do nothing */
}
} catch (Exception ignored) {
doPrivileged = null;
}
return doPrivileged;
}
/**
* A description of the method to be loaded onto the stack.
*/
protected final MethodDescription.InDefinedShape methodDescription;
/**
* Creates a new method constant.
*
* @param methodDescription The method description for which the {@link java.lang.reflect.Method} representation
* should be created.
*/
protected MethodConstant(MethodDescription.InDefinedShape methodDescription) {
this.methodDescription = methodDescription;
}
/**
* Creates a stack manipulation that loads a method constant onto the operand stack.
*
* @param methodDescription The method to be loaded onto the stack.
* @return A stack manipulation that assigns a method constant for the given method description.
*/
public static CanCache of(MethodDescription.InDefinedShape methodDescription) {
if (methodDescription.isTypeInitializer()) {
return CanCacheIllegal.INSTANCE;
} else if (methodDescription.isConstructor()) {
return new ForConstructor(methodDescription);
} else {
return new ForMethod(methodDescription);
}
}
/**
* Creates a stack manipulation that loads a method constant onto the operand stack using an {@code java.security.AccessController}.
* If the current VM does not support the access controller API, or if {@code net.bytebuddy.securitymanager} is set to false, this
* method has the same effect as {@link MethodConstant#of(MethodDescription.InDefinedShape)}.
*
* @param methodDescription The method to be loaded onto the stack.
* @return A stack manipulation that assigns a method constant for the given method description.
*/
public static CanCache ofPrivileged(MethodDescription.InDefinedShape methodDescription) {
if (DO_PRIVILEGED == null) {
return of(methodDescription);
}
if (methodDescription.isTypeInitializer()) {
return CanCacheIllegal.INSTANCE;
} else if (methodDescription.isConstructor()) {
return new ForConstructor(methodDescription).withPrivilegedLookup();
} else {
return new ForMethod(methodDescription).withPrivilegedLookup();
}
}
/**
* Returns a list of type constant load operations for the given list of parameters.
*
* @param parameterTypes A list of all type descriptions that should be represented as type constant
* load operations.
* @return A corresponding list of type constant load operations.
*/
protected static List typeConstantsFor(List parameterTypes) {
List typeConstants = new ArrayList(parameterTypes.size());
for (TypeDescription parameterType : parameterTypes) {
typeConstants.add(ClassConstant.of(parameterType));
}
return typeConstants;
}
/**
* {@inheritDoc}
*/
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
return new Compound(
ClassConstant.of(methodDescription.getDeclaringType()),
methodName(),
ArrayFactory.forType(TypeDescription.Generic.OfNonGenericType.ForLoadedType.of(Class.class))
.withValues(typeConstantsFor(methodDescription.getParameters().asTypeList().asErasures())),
MethodInvocation.invoke(accessorMethod())
).apply(methodVisitor, implementationContext);
}
/**
* Returns a method constant that uses an {@code java.security.AccessController} to look up this constant.
*
* @return A method constant that uses an {@code java.security.AccessController} to look up this constant.
*/
protected CanCache withPrivilegedLookup() {
return new PrivilegedLookup(methodDescription, methodName());
}
/**
* Returns a stack manipulation that loads the method name onto the operand stack if this is required.
*
* @return A stack manipulation that loads the method name onto the operand stack if this is required.
*/
protected abstract StackManipulation methodName();
/**
* Returns the method for loading a declared method or constructor onto the operand stack.
*
* @return The method for loading a declared method or constructor onto the operand stack.
*/
protected abstract MethodDescription.InDefinedShape accessorMethod();
@Override
public int hashCode() {
return methodDescription.hashCode();
}
@Override
public boolean equals(@MaybeNull Object other) {
if (this == other) {
return true;
} else if (other == null || getClass() != other.getClass()) {
return false;
}
MethodConstant methodConstant = (MethodConstant) other;
return methodDescription.equals(methodConstant.methodDescription);
}
/**
* Represents a method constant that cannot be represented by Java's reflection API.
*/
protected enum CanCacheIllegal implements CanCache {
/**
* The singleton instance.
*/
INSTANCE;
/**
* {@inheritDoc}
*/
public StackManipulation cached() {
return Illegal.INSTANCE;
}
/**
* {@inheritDoc}
*/
public boolean isValid() {
return false;
}
/**
* {@inheritDoc}
*/
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
return Illegal.INSTANCE.apply(methodVisitor, implementationContext);
}
}
/**
* Represents a {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant} that is
* directly loaded onto the operand stack without caching the value. Since the look-up of a Java method bares
* some costs that sometimes need to be avoided, such a stack manipulation offers a convenience method for
* defining this loading instruction as the retrieval of a field value that is initialized in the instrumented
* type's type initializer.
*/
public interface CanCache extends StackManipulation {
/**
* Returns this method constant as a cached version.
*
* @return A cached version of the method constant that is represented by this instance.
*/
StackManipulation cached();
}
/**
* Creates a {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant} for loading
* a {@link java.lang.reflect.Method} instance onto the operand stack.
*/
protected static class ForMethod extends MethodConstant implements CanCache {
/**
* The {@link Class#getMethod(String, Class[])} method.
*/
private static final MethodDescription.InDefinedShape GET_METHOD;
/**
* The {@link Class#getDeclaredMethod(String, Class[])} method.
*/
private static final MethodDescription.InDefinedShape GET_DECLARED_METHOD;
/*
* Looks up methods used for creating the manipulation.
*/
static {
try {
GET_METHOD = new MethodDescription.ForLoadedMethod(Class.class.getMethod("getMethod", String.class, Class[].class));
GET_DECLARED_METHOD = new MethodDescription.ForLoadedMethod(Class.class.getMethod("getDeclaredMethod", String.class, Class[].class));
} catch (NoSuchMethodException exception) {
throw new IllegalStateException("Could not locate method lookup", exception);
}
}
/**
* Creates a new {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant} for
* creating a {@link java.lang.reflect.Method} instance.
*
* @param methodDescription The method to be loaded onto the stack.
*/
protected ForMethod(MethodDescription.InDefinedShape methodDescription) {
super(methodDescription);
}
@Override
protected StackManipulation methodName() {
return new TextConstant(methodDescription.getInternalName());
}
@Override
protected MethodDescription.InDefinedShape accessorMethod() {
return methodDescription.isPublic()
? GET_METHOD
: GET_DECLARED_METHOD;
}
/**
* {@inheritDoc}
*/
public StackManipulation cached() {
return new CachedMethod(this);
}
}
/**
* Creates a {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant} for loading
* a {@link java.lang.reflect.Constructor} instance onto the operand stack.
*/
protected static class ForConstructor extends MethodConstant implements CanCache {
/**
* The {@link Class#getConstructor(Class[])} method.
*/
private static final MethodDescription.InDefinedShape GET_CONSTRUCTOR;
/**
* The {@link Class#getDeclaredConstructor(Class[])} method.
*/
private static final MethodDescription.InDefinedShape GET_DECLARED_CONSTRUCTOR;
/*
* Looks up the method used for creating the manipulation.
*/
static {
try {
GET_CONSTRUCTOR = new MethodDescription.ForLoadedMethod(Class.class.getMethod("getConstructor", Class[].class));
GET_DECLARED_CONSTRUCTOR = new MethodDescription.ForLoadedMethod(Class.class.getMethod("getDeclaredConstructor", Class[].class));
} catch (NoSuchMethodException exception) {
throw new IllegalStateException("Could not locate Class::getDeclaredConstructor", exception);
}
}
/**
* Creates a new {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant} for
* creating a {@link java.lang.reflect.Constructor} instance.
*
* @param methodDescription The constructor to be loaded onto the stack.
*/
protected ForConstructor(MethodDescription.InDefinedShape methodDescription) {
super(methodDescription);
}
@Override
protected StackManipulation methodName() {
return Trivial.INSTANCE;
}
@Override
protected MethodDescription.InDefinedShape accessorMethod() {
return methodDescription.isPublic()
? GET_CONSTRUCTOR
: GET_DECLARED_CONSTRUCTOR;
}
/**
* {@inheritDoc}
*/
public StackManipulation cached() {
return new CachedConstructor(this);
}
}
/**
* Performs a privileged lookup of a method constant by using an {@code java.security.AccessController}.
*/
protected static class PrivilegedLookup implements StackManipulation, CanCache {
/**
* The method constant to load.
*/
private final MethodDescription.InDefinedShape methodDescription;
/**
* The stack manipulation for locating the method name.
*/
private final StackManipulation methodName;
/**
* Creates a new privileged lookup.
*
* @param methodDescription The method constant to load.
* @param methodName The stack manipulation for locating the method name.
*/
protected PrivilegedLookup(MethodDescription.InDefinedShape methodDescription, StackManipulation methodName) {
this.methodDescription = methodDescription;
this.methodName = methodName;
}
/**
* {@inheritDoc}
*/
public boolean isValid() {
return methodName.isValid();
}
/**
* {@inheritDoc}
*/
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
if (DO_PRIVILEGED == null) {
throw new IllegalStateException("Privileged method invocation is not supported on the current VM");
}
TypeDescription auxiliaryType = implementationContext.register(PrivilegedMemberLookupAction.of(methodDescription));
return new Compound(
TypeCreation.of(auxiliaryType),
Duplication.SINGLE,
ClassConstant.of(methodDescription.getDeclaringType()),
methodName,
ArrayFactory.forType(TypeDescription.Generic.OfNonGenericType.ForLoadedType.of(Class.class))
.withValues(typeConstantsFor(methodDescription.getParameters().asTypeList().asErasures())),
MethodInvocation.invoke(auxiliaryType.getDeclaredMethods().filter(isConstructor()).getOnly()),
MethodInvocation.invoke(DO_PRIVILEGED),
TypeCasting.to(TypeDescription.ForLoadedType.of(methodDescription.isConstructor()
? Constructor.class
: Method.class))
).apply(methodVisitor, implementationContext);
}
/**
* {@inheritDoc}
*/
public StackManipulation cached() {
return methodDescription.isConstructor()
? new CachedConstructor(this)
: new CachedMethod(this);
}
@Override
public int hashCode() {
return methodDescription.hashCode();
}
@Override
public boolean equals(@MaybeNull Object other) {
if (this == other) {
return true;
} else if (other == null || getClass() != other.getClass()) {
return false;
}
PrivilegedLookup privilegedLookup = (PrivilegedLookup) other;
return methodDescription.equals(privilegedLookup.methodDescription);
}
}
/**
* Represents a cached method for a {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant}.
*/
protected static class CachedMethod implements StackManipulation {
/**
* A description of the {@link java.lang.reflect.Method} type.
*/
private static final TypeDescription METHOD_TYPE = TypeDescription.ForLoadedType.of(Method.class);
/**
* The stack manipulation that is represented by this caching wrapper.
*/
private final StackManipulation methodConstant;
/**
* Creates a new cached {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant}.
*
* @param methodConstant The method constant to store in the field cache.
*/
protected CachedMethod(StackManipulation methodConstant) {
this.methodConstant = methodConstant;
}
/**
* {@inheritDoc}
*/
public boolean isValid() {
return methodConstant.isValid();
}
/**
* {@inheritDoc}
*/
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
return FieldAccess.forField(implementationContext.cache(methodConstant, METHOD_TYPE))
.read()
.apply(methodVisitor, implementationContext);
}
@Override
public int hashCode() {
return methodConstant.hashCode();
}
@Override
public boolean equals(@MaybeNull Object other) {
if (this == other) {
return true;
} else if (other == null || getClass() != other.getClass()) {
return false;
}
CachedMethod cachedMethod = (CachedMethod) other;
return methodConstant.equals(cachedMethod.methodConstant);
}
}
/**
* Represents a cached constructor for a {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant}.
*/
protected static class CachedConstructor implements StackManipulation {
/**
* A description of the {@link java.lang.reflect.Constructor} type.
*/
private static final TypeDescription CONSTRUCTOR_TYPE = TypeDescription.ForLoadedType.of(Constructor.class);
/**
* The stack manipulation that is represented by this caching wrapper.
*/
private final StackManipulation constructorConstant;
/**
* Creates a new cached {@link net.bytebuddy.implementation.bytecode.constant.MethodConstant}.
*
* @param constructorConstant The method constant to store in the field cache.
*/
protected CachedConstructor(StackManipulation constructorConstant) {
this.constructorConstant = constructorConstant;
}
/**
* {@inheritDoc}
*/
public boolean isValid() {
return constructorConstant.isValid();
}
/**
* {@inheritDoc}
*/
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
return FieldAccess.forField(implementationContext.cache(constructorConstant, CONSTRUCTOR_TYPE))
.read()
.apply(methodVisitor, implementationContext);
}
@Override
public int hashCode() {
return constructorConstant.hashCode();
}
@Override
public boolean equals(@MaybeNull Object other) {
if (this == other) {
return true;
} else if (other == null || getClass() != other.getClass()) {
return false;
}
CachedConstructor cachedConstructor = (CachedConstructor) other;
return constructorConstant.equals(cachedConstructor.constructorConstant);
}
}
}