kotlin.jvm.internal.CallableReference Maven / Gradle / Ivy
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* Copyright 2010-2015 JetBrains s.r.o.
*
* 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 kotlin.jvm.internal;
import kotlin.SinceKotlin;
import kotlin.jvm.KotlinReflectionNotSupportedError;
import kotlin.reflect.*;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import java.io.ObjectStreamException;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.util.List;
import java.util.Map;
/**
* A superclass for all classes generated by Kotlin compiler for callable references.
*
* All methods from KCallable should be implemented here and should delegate to the actual implementation, loaded dynamically
* and stored in the {@link CallableReference#reflected} field.
*/
@SuppressWarnings({"unchecked", "NullableProblems"})
public abstract class CallableReference implements KCallable, Serializable {
// This field is not volatile intentionally:
// 1) It's fine if the value is computed multiple times in different threads;
// 2) An uninitialized value cannot be observed in this field from other thread because only already initialized or safely initialized
// objects are written to it. The latter is guaranteed because both KFunctionImpl and KPropertyImpl have at least one final field.
private transient KCallable reflected;
@SinceKotlin(version = "1.1")
protected final Object receiver;
@SinceKotlin(version = "1.1")
public static final Object NO_RECEIVER = NoReceiver.INSTANCE;
@SinceKotlin(version = "1.2")
private static class NoReceiver implements Serializable {
private static final NoReceiver INSTANCE = new NoReceiver();
private Object readResolve() throws ObjectStreamException {
return INSTANCE;
}
}
public CallableReference() {
this(NO_RECEIVER);
}
@SinceKotlin(version = "1.1")
protected CallableReference(Object receiver) {
this.receiver = receiver;
}
protected abstract KCallable computeReflected();
@SinceKotlin(version = "1.1")
public Object getBoundReceiver() {
return receiver;
}
@SinceKotlin(version = "1.1")
public KCallable compute() {
KCallable result = reflected;
if (result == null) {
result = computeReflected();
reflected = result;
}
return result;
}
@SinceKotlin(version = "1.1")
protected KCallable getReflected() {
KCallable result = compute();
if (result == this) {
throw new KotlinReflectionNotSupportedError();
}
return result;
}
// The following methods provide the information identifying this callable, which is used by the reflection implementation.
// They are supposed to be overridden in each subclass (each anonymous class generated for a callable reference).
/**
* @return the class or package where the callable should be located, usually specified on the LHS of the '::' operator
*/
public KDeclarationContainer getOwner() {
throw new AbstractMethodError();
}
/**
* @return Kotlin name of the callable, the one which was declared in the source code (@JvmName doesn't change it)
*/
@Override
public String getName() {
throw new AbstractMethodError();
}
/**
* @return JVM signature of the callable, e.g. "println(Ljava/lang/Object;)V". If this is a property reference,
* returns the JVM signature of its getter, e.g. "getFoo(Ljava/lang/String;)I". If the property has no getter in the bytecode
* (e.g. private property in a class), it's still the signature of the imaginary default getter that would be generated otherwise.
*
* Note that technically the signature itself is not even used as a signature per se in reflection implementation,
* but only as a unique and unambiguous way to map a function/property descriptor to a string.
*/
public String getSignature() {
throw new AbstractMethodError();
}
// The following methods are the delegating implementations of reflection functions. They are called when you're using reflection
// on a callable reference. Without kotlin-reflect.jar in the classpath, getReflected() throws an exception.
@Override
public List getParameters() {
return getReflected().getParameters();
}
@Override
public KType getReturnType() {
return getReflected().getReturnType();
}
@Override
public List getAnnotations() {
return getReflected().getAnnotations();
}
@NotNull
@Override
@SinceKotlin(version = "1.1")
public List getTypeParameters() {
return getReflected().getTypeParameters();
}
@Override
public Object call(@NotNull Object... args) {
return getReflected().call(args);
}
@Override
public Object callBy(@NotNull Map args) {
return getReflected().callBy(args);
}
@Nullable
@Override
@SinceKotlin(version = "1.1")
public KVisibility getVisibility() {
return getReflected().getVisibility();
}
@Override
@SinceKotlin(version = "1.1")
public boolean isFinal() {
return getReflected().isFinal();
}
@Override
@SinceKotlin(version = "1.1")
public boolean isOpen() {
return getReflected().isOpen();
}
@Override
@SinceKotlin(version = "1.1")
public boolean isAbstract() {
return getReflected().isAbstract();
}
}