org.glassfish.pfl.basic.reflection.BridgeBase Maven / Gradle / Ivy
/*
* Copyright (c) 2018, 2019 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0, which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.glassfish.pfl.basic.reflection;
import sun.misc.Unsafe;
import java.io.OptionalDataException;
import java.lang.invoke.MethodHandle;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.ProtectionDomain;
public abstract class BridgeBase {
/**
* This constant differs from all results that will ever be returned from
* {@link #objectFieldOffset}.
*/
public static final long INVALID_FIELD_OFFSET = -1;
private final Unsafe unsafe = AccessController.doPrivileged(
new PrivilegedAction() {
public Unsafe run() {
try {
Field field = Unsafe.class.getDeclaredField("theUnsafe");
field.setAccessible(true);
return (Unsafe) field.get(null);
} catch (NoSuchFieldException | IllegalAccessException exc) {
throw new Error("Could not access Unsafe", exc);
}
}
}
);
/**
* Fetches a field element within the given
* object o at the given offset.
* The result is undefined unless the offset was obtained from
* {@link #objectFieldOffset} on the {@link java.lang.reflect.Field}
* of some Java field and the object referred to by o
* is of a class compatible with that field's class.
*
* @param o Java heap object in which the field from which the offset
* was obtained resides
* @param offset indication of where the field resides in a Java heap
* object
* @return the value fetched from the indicated Java field
* @throws RuntimeException No defined exceptions are thrown, not even
* {@link NullPointerException}
*/
public final int getInt(Object o, long offset) {
return unsafe.getInt(o, offset);
}
/**
* Stores a value into a given Java field.
*
* The first two parameters are interpreted exactly as with
* {@link #getInt(Object, long)} to refer to a specific
* Java field. The given value is stored into that field.
*
* The field must be of the same type as the method
* parameter x.
*
* @param o Java heap object in which the field resides, if any, else
* null
* @param offset indication of where the field resides in a Java heap
* object.
* @param x the value to store into the indicated Java field
* @throws RuntimeException No defined exceptions are thrown, not even
* {@link NullPointerException}
*/
public final void putInt(Object o, long offset, int x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putInt(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
@SuppressWarnings("unchecked")
public final T getObject(Object o, long offset) {
return (T) unsafe.getObject(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putObject(Object o, long offset, Object x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putObject(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final boolean getBoolean(Object o, long offset) {
return unsafe.getBoolean(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putBoolean(Object o, long offset, boolean x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putBoolean(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final byte getByte(Object o, long offset) {
return unsafe.getByte(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putByte(Object o, long offset, byte x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putByte(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final short getShort(Object o, long offset) {
return unsafe.getShort(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putShort(Object o, long offset, short x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putShort(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final char getChar(Object o, long offset) {
return unsafe.getChar(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putChar(Object o, long offset, char x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putChar(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final long getLong(Object o, long offset) {
return unsafe.getLong(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putLong(Object o, long offset, long x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putLong(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final float getFloat(Object o, long offset) {
return unsafe.getFloat(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putFloat(Object o, long offset, float x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putFloat(o, offset, x);
}
/**
* @see #getInt(Object, long)
*/
public final double getDouble(Object o, long offset) {
return unsafe.getDouble(o, offset);
}
/**
* @see #putInt(Object, long, int)
*/
public final void putDouble(Object o, long offset, double x) {
if (offset != INVALID_FIELD_OFFSET)
unsafe.putDouble(o, offset, x);
}
/**
* Returns the offset of a non-static field, which can be passed into the set... or get... methods.
* @see #getInt(Object, long)
*/
public final long objectFieldOffset(Field f) {
return unsafe.objectFieldOffset(f);
}
public final long staticFieldOffset(Field f) {
return unsafe.staticFieldOffset(f);
}
/**
* Throw the exception.
* The exception may be an undeclared checked exception.
*/
public final void throwException(Throwable ee) {
unsafe.throwException(ee);
}
/**
* Defines a class is a specified classloader.
* @param className the name of the class
* @param classBytes the byte code for the class
* @param classLoader the classloader in which it is to be defined
* @param protectionDomain the domain in which the class should be defined
*
* @deprecated will not work in Java 11 or later. Use {@link #defineClass(Class, String, byte[])} instead
*/
@SuppressWarnings("DeprecatedIsStillUsed")
@Deprecated
public Class defineClass(String className, byte[] classBytes, ClassLoader classLoader, ProtectionDomain protectionDomain) {
return unsafe.defineClass(className, classBytes, 0, classBytes.length, classLoader, null);
}
/**
* Defines a new class from bytecode. The class will be defined in the classloader and package associated with a
* specified 'anchor class'.
*
* @param anchorClass the class from which the package and classloader of the new class are to be taken.
* @param className the name of the class to define
* @param classBytes the bytes used to define the class
* @return a new instantiable class, in the package and classloader of the anchor class.
*/
@SuppressWarnings("deprecation")
public Class defineClass(Class anchorClass, String className, byte[] classBytes) {
return defineClass(className, classBytes, anchorClass.getClassLoader(), null);
}
/**
* Ensure that the class has been initialized.
* @param cl the class to ensure is initialized
*/
public final void ensureClassInitialized(Class cl) {
unsafe.ensureClassInitialized(cl);
}
/**
* Obtain the latest user defined ClassLoader from the call stack.
* This is required by the RMI-IIOP specification.
*/
public abstract ClassLoader getLatestUserDefinedLoader();
/**
* Return a constructor that can be used to create an instance of the class for externalization.
* @param cl the class
*/
public abstract Constructor newConstructorForExternalization(Class cl);
/**
* Return a no-arg constructor for the specified class which invokes the specified constructor.
*
* @param aClass the class for which a constructor should be returned.
* @param cons the default constructor on which to model the new constructor.
*/
public abstract Constructor newConstructorForSerialization(Class aClass, Constructor cons);
/**
* Return a no-arg constructor for the specified class, based on the default constructor
* for its nearest non-serializable base class.
* @param aClass the class for which a constructor should be returned.
*/
public abstract Constructor newConstructorForSerialization(Class aClass);
/**
* Returns true if the given class defines a static initializer method,
* false otherwise.
*/
public abstract boolean hasStaticInitializerForSerialization(Class cl);
/**
* Returns a method handle to allow invocation of the specified class's writeObject method.
* @param cl the class containing the method
*/
public abstract MethodHandle writeObjectForSerialization(Class cl) throws NoSuchMethodException, IllegalAccessException;
/**
* Returns a method handle to allow invocation of the specified class's readObject method.
* @param cl the class containing the method
*/
public abstract MethodHandle readObjectForSerialization(Class cl) throws NoSuchMethodException, IllegalAccessException;
/**
* Returns a method handle to allow invocation of the specified class's readResolve method.
* @param cl the class containing the method
*/
public abstract MethodHandle readResolveForSerialization(Class cl);
/**
* Returns a method handle to allow invocation of the specified class's writeReplace method.
* @param cl the class containing the method
*/
public abstract MethodHandle writeReplaceForSerialization(Class cl);
/**
* Return a new OptionalDataException instance.
* @return a new OptionalDataException instance
*/
public abstract OptionalDataException newOptionalDataExceptionForSerialization(boolean bool);
/**
* Returns the specified field after calling setAccessible, if it is accessible from the specified class.
* @param field the field to make accessible
* @param callingClass the class which wants to access it.
* @return the original field, rendered accessible, or null.
*/
public Field toAccessibleField(Field field, Class callingClass) {
field.setAccessible(true);
return field;
}
/**
* Returns the specified method after calling setAccessible, if it is accessible from the specified class.
* @param method the method to make accessible
* @param callingClass the class which wants to access it.
* @return the original method, rendered accessible, or null.
*/
public Method toAccessibleMethod(Method method, Class callingClass) {
method.setAccessible(true);
return method;
}
}