--- old/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/NashornBeansLinker.java 2020-04-15 18:51:07.000000000 +0530 +++ /dev/null 2020-04-15 18:51:07.000000000 +0530 @@ -1,301 +0,0 @@ -/* - * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This code is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 only, as - * published by the Free Software Foundation. Oracle designates this - * particular file as subject to the "Classpath" exception as provided - * by Oracle in the LICENSE file that accompanied this code. - * - * This code is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * version 2 for more details (a copy is included in the LICENSE file that - * accompanied this code). - * - * You should have received a copy of the GNU General Public License version - * 2 along with this work; if not, write to the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA - * or visit www.oracle.com if you need additional information or have any - * questions. - */ - -package jdk.nashorn.internal.runtime.linker; - -import static jdk.nashorn.internal.lookup.Lookup.MH; - -import java.lang.invoke.MethodHandle; -import java.lang.invoke.MethodHandles; -import java.lang.invoke.MethodType; -import java.lang.reflect.Method; -import java.lang.reflect.Modifier; -import java.util.function.Supplier; -import jdk.dynalink.CallSiteDescriptor; -import jdk.dynalink.NamedOperation; -import jdk.dynalink.Operation; -import jdk.dynalink.SecureLookupSupplier; -import jdk.dynalink.StandardNamespace; -import jdk.dynalink.StandardOperation; -import jdk.dynalink.beans.BeansLinker; -import jdk.dynalink.linker.ConversionComparator.Comparison; -import jdk.dynalink.linker.GuardedInvocation; -import jdk.dynalink.linker.GuardingDynamicLinker; -import jdk.dynalink.linker.LinkRequest; -import jdk.dynalink.linker.LinkerServices; -import jdk.dynalink.linker.MethodHandleTransformer; -import jdk.dynalink.linker.support.DefaultInternalObjectFilter; -import jdk.dynalink.linker.support.Lookup; -import jdk.dynalink.linker.support.SimpleLinkRequest; -import jdk.nashorn.api.scripting.ScriptUtils; -import jdk.nashorn.internal.runtime.ConsString; -import jdk.nashorn.internal.runtime.Context; -import jdk.nashorn.internal.runtime.ScriptObject; -import jdk.nashorn.internal.runtime.options.Options; - -/** - * This linker delegates to a {@code BeansLinker} but passes it a special linker services object that has a modified - * {@code compareConversion} method that favors conversion of {@link ConsString} to either {@link String} or - * {@link CharSequence}. It also provides a {@link #createHiddenObjectFilter()} method for use with bootstrap that will - * ensure that we never pass internal engine objects that should not be externally observable (currently ConsString and - * ScriptObject) to Java APIs, but rather that we flatten it into a String. We can't just add this functionality as - * custom converters via {@code GuaardingTypeConverterFactory}, since they are not consulted when - * the target method handle parameter signature is {@code Object}. This linker also makes sure that primitive - * {@link String} operations can be invoked on a {@link ConsString}, and allows invocation of objects implementing - * the {@link FunctionalInterface} attribute. - */ -public class NashornBeansLinker implements GuardingDynamicLinker { - // System property to control whether to wrap ScriptObject->ScriptObjectMirror for - // Object type arguments of Java method calls, field set and array set. - private static final boolean MIRROR_ALWAYS = Options.getBooleanProperty("nashorn.mirror.always", true); - - private static final Operation GET_METHOD = StandardOperation.GET.withNamespace(StandardNamespace.METHOD); - private static final MethodType GET_METHOD_TYPE = MethodType.methodType(Object.class, Object.class); - - private static final MethodHandle EXPORT_ARGUMENT; - private static final MethodHandle IMPORT_RESULT; - private static final MethodHandle FILTER_CONSSTRING; - - static { - final Lookup lookup = new Lookup(MethodHandles.lookup()); - EXPORT_ARGUMENT = lookup.findOwnStatic("exportArgument", Object.class, Object.class); - IMPORT_RESULT = lookup.findOwnStatic("importResult", Object.class, Object.class); - FILTER_CONSSTRING = lookup.findOwnStatic("consStringFilter", Object.class, Object.class); - } - - // cache of @FunctionalInterface method of implementor classes - private static final ClassValue FUNCTIONAL_IFACE_METHOD_NAME = new ClassValue() { - @Override - protected String computeValue(final Class type) { - return findFunctionalInterfaceMethodName(type); - } - }; - - private final BeansLinker beansLinker; - - NashornBeansLinker(final BeansLinker beansLinker) { - this.beansLinker = beansLinker; - } - - @Override - public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest, final LinkerServices linkerServices) throws Exception { - final Object self = linkRequest.getReceiver(); - final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor(); - if (self instanceof ConsString) { - // In order to treat ConsString like a java.lang.String we need a link request with a string receiver. - final Object[] arguments = linkRequest.getArguments(); - arguments[0] = ""; - final LinkRequest forgedLinkRequest = linkRequest.replaceArguments(desc, arguments); - final GuardedInvocation invocation = getGuardedInvocation(beansLinker, forgedLinkRequest, linkerServices); - // If an invocation is found we add a filter that makes it work for both Strings and ConsStrings. - return invocation == null ? null : invocation.filterArguments(0, FILTER_CONSSTRING); - } - - if (self != null && NamedOperation.getBaseOperation(desc.getOperation()) == StandardOperation.CALL) { - // Support CALL on any object that supports some @FunctionalInterface - // annotated interface. This way Java method, constructor references or - // implementations of java.util.function.* interfaces can be called as though - // those are script functions. - final String name = getFunctionalInterfaceMethodName(self.getClass()); - if (name != null) { - // Obtain the method - final CallSiteDescriptor getMethodDesc = new CallSiteDescriptor( - NashornCallSiteDescriptor.getLookupInternal(desc), - GET_METHOD.named(name), GET_METHOD_TYPE); - final GuardedInvocation getMethodInv = linkerServices.getGuardedInvocation( - new SimpleLinkRequest(getMethodDesc, false, self)); - final Object method; - try { - method = getMethodInv.getInvocation().invokeExact(self); - } catch (final Exception|Error e) { - throw e; - } catch (final Throwable t) { - throw new RuntimeException(t); - } - - final Object[] args = linkRequest.getArguments(); - args[1] = args[0]; // callee (the functional object) becomes this - args[0] = method; // the method becomes the callee - - final MethodType callType = desc.getMethodType(); - - final CallSiteDescriptor newDesc = desc.changeMethodType( - desc.getMethodType().changeParameterType(0, Object.class).changeParameterType(1, callType.parameterType(0))); - final GuardedInvocation gi = getGuardedInvocation(beansLinker, linkRequest.replaceArguments(newDesc, args), - new NashornBeansLinkerServices(linkerServices)); - - // Bind to the method, drop the original "this" and use original "callee" as this: - final MethodHandle inv = gi.getInvocation() // (method, this, args...) - .bindTo(method); // (this, args...) - final MethodHandle calleeToThis = MH.dropArguments(inv, 1, callType.parameterType(1)); // (callee->this, , args...) - return gi.replaceMethods(calleeToThis, gi.getGuard()); - } - } - return getGuardedInvocation(beansLinker, linkRequest, linkerServices); - } - - /** - * Delegates to the specified linker but injects its linker services wrapper so that it will apply all special - * conversions that this class does. - * @param delegateLinker the linker to which the actual work is delegated to. - * @param linkRequest the delegated link request - * @param linkerServices the original link services that will be augmented with special conversions - * @return the guarded invocation from the delegate, possibly augmented with special conversions - * @throws Exception if the delegate throws an exception - */ - public static GuardedInvocation getGuardedInvocation(final GuardingDynamicLinker delegateLinker, final LinkRequest linkRequest, final LinkerServices linkerServices) throws Exception { - return delegateLinker.getGuardedInvocation(linkRequest, new NashornBeansLinkerServices(linkerServices)); - } - - @SuppressWarnings("unused") - private static Object exportArgument(final Object arg) { - return exportArgument(arg, MIRROR_ALWAYS); - } - - static Object exportArgument(final Object arg, final boolean mirrorAlways) { - if (arg instanceof ConsString) { - return arg.toString(); - } else if (mirrorAlways && arg instanceof ScriptObject) { - return ScriptUtils.wrap(arg); - } else { - return arg; - } - } - - @SuppressWarnings("unused") - private static Object importResult(final Object arg) { - return ScriptUtils.unwrap(arg); - } - - @SuppressWarnings("unused") - private static Object consStringFilter(final Object arg) { - return arg instanceof ConsString ? arg.toString() : arg; - } - - private static String findFunctionalInterfaceMethodName(final Class clazz) { - if (clazz == null) { - return null; - } - - for (final Class iface : clazz.getInterfaces()) { - // check accessibility up-front - if (! Context.isAccessibleClass(iface)) { - continue; - } - - // check for @FunctionalInterface - if (iface.isAnnotationPresent(FunctionalInterface.class)) { - // return the first abstract method - for (final Method m : iface.getMethods()) { - if (Modifier.isAbstract(m.getModifiers()) && !isOverridableObjectMethod(m)) { - return m.getName(); - } - } - } - } - - // did not find here, try super class - return findFunctionalInterfaceMethodName(clazz.getSuperclass()); - } - - // is this an overridable java.lang.Object method? - private static boolean isOverridableObjectMethod(final Method m) { - switch (m.getName()) { - case "equals": - if (m.getReturnType() == boolean.class) { - final Class[] params = m.getParameterTypes(); - return params.length == 1 && params[0] == Object.class; - } - return false; - case "hashCode": - return m.getReturnType() == int.class && m.getParameterCount() == 0; - case "toString": - return m.getReturnType() == String.class && m.getParameterCount() == 0; - } - return false; - } - - // Returns @FunctionalInterface annotated interface's single abstract - // method name. If not found, returns null. - static String getFunctionalInterfaceMethodName(final Class clazz) { - return FUNCTIONAL_IFACE_METHOD_NAME.get(clazz); - } - - static MethodHandleTransformer createHiddenObjectFilter() { - return new DefaultInternalObjectFilter(EXPORT_ARGUMENT, MIRROR_ALWAYS ? IMPORT_RESULT : null); - } - - private static class NashornBeansLinkerServices implements LinkerServices { - private final LinkerServices linkerServices; - - NashornBeansLinkerServices(final LinkerServices linkerServices) { - this.linkerServices = linkerServices; - } - - @Override - public MethodHandle asType(final MethodHandle handle, final MethodType fromType) { - return linkerServices.asType(handle, fromType); - } - - @Override - public MethodHandle getTypeConverter(final Class sourceType, final Class targetType) { - return linkerServices.getTypeConverter(sourceType, targetType); - } - - @Override - public boolean canConvert(final Class from, final Class to) { - return linkerServices.canConvert(from, to); - } - - @Override - public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest) throws Exception { - return linkerServices.getGuardedInvocation(linkRequest); - } - - @Override - public Comparison compareConversion(final Class sourceType, final Class targetType1, final Class targetType2) { - if (sourceType == ConsString.class) { - if (String.class == targetType1 || CharSequence.class == targetType1) { - return Comparison.TYPE_1_BETTER; - } - - if (String.class == targetType2 || CharSequence.class == targetType2) { - return Comparison.TYPE_2_BETTER; - } - } - return linkerServices.compareConversion(sourceType, targetType1, targetType2); - } - - @Override - public MethodHandle filterInternalObjects(final MethodHandle target) { - return linkerServices.filterInternalObjects(target); - } - - @Override - public T getWithLookup(final Supplier operation, final SecureLookupSupplier lookupSupplier) { - return linkerServices.getWithLookup(operation, lookupSupplier); - } - } -}