NashornBeansLinker.java revision 1186:4a2dfd2ec3f3
11556Srgrimes/* 21556Srgrimes * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. 31556Srgrimes * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 41556Srgrimes * 51556Srgrimes * This code is free software; you can redistribute it and/or modify it 61556Srgrimes * under the terms of the GNU General Public License version 2 only, as 71556Srgrimes * published by the Free Software Foundation. Oracle designates this 81556Srgrimes * particular file as subject to the "Classpath" exception as provided 91556Srgrimes * by Oracle in the LICENSE file that accompanied this code. 101556Srgrimes * 111556Srgrimes * This code is distributed in the hope that it will be useful, but WITHOUT 121556Srgrimes * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 131556Srgrimes * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 141556Srgrimes * version 2 for more details (a copy is included in the LICENSE file that 151556Srgrimes * accompanied this code). 161556Srgrimes * 171556Srgrimes * You should have received a copy of the GNU General Public License version 181556Srgrimes * 2 along with this work; if not, write to the Free Software Foundation, 191556Srgrimes * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 201556Srgrimes * 211556Srgrimes * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 221556Srgrimes * or visit www.oracle.com if you need additional information or have any 231556Srgrimes * questions. 241556Srgrimes */ 251556Srgrimes 261556Srgrimespackage jdk.nashorn.internal.runtime.linker; 271556Srgrimes 281556Srgrimesimport static jdk.nashorn.internal.lookup.Lookup.MH; 291556Srgrimesimport static jdk.nashorn.internal.runtime.ECMAErrors.typeError; 301556Srgrimes 311556Srgrimesimport java.lang.invoke.MethodHandle; 321556Srgrimesimport java.lang.invoke.MethodHandles; 331556Srgrimesimport java.lang.invoke.MethodType; 341556Srgrimesimport java.lang.reflect.Method; 351556Srgrimesimport java.lang.reflect.Modifier; 361556Srgrimesimport jdk.internal.dynalink.CallSiteDescriptor; 371556Srgrimesimport jdk.internal.dynalink.beans.BeansLinker; 3836150Scharnierimport jdk.internal.dynalink.linker.ConversionComparator.Comparison; 3936150Scharnierimport jdk.internal.dynalink.linker.GuardedInvocation; 4036150Scharnierimport jdk.internal.dynalink.linker.GuardingDynamicLinker; 4136150Scharnierimport jdk.internal.dynalink.linker.LinkRequest; 4250471Speterimport jdk.internal.dynalink.linker.LinkerServices; 431556Srgrimesimport jdk.internal.dynalink.linker.MethodHandleTransformer; 441556Srgrimesimport jdk.internal.dynalink.support.DefaultInternalObjectFilter; 4517987Speterimport jdk.internal.dynalink.support.Guards; 4617987Speterimport jdk.internal.dynalink.support.Lookup; 4717987Speterimport jdk.nashorn.api.scripting.ScriptUtils; 4817987Speterimport jdk.nashorn.internal.runtime.ConsString; 4917987Speterimport jdk.nashorn.internal.runtime.Context; 5017987Speterimport jdk.nashorn.internal.runtime.ScriptObject; 5117987Speterimport jdk.nashorn.internal.runtime.ScriptRuntime; 5217987Speterimport jdk.nashorn.internal.runtime.options.Options; 5317987Speter 5417987Speter/** 5569793Sobrien * This linker delegates to a {@code BeansLinker} but passes it a special linker services object that has a modified 5617987Speter * {@code compareConversion} method that favors conversion of {@link ConsString} to either {@link String} or 5718018Speter * {@link CharSequence}. It also provides a {@link #createHiddenObjectFilter()} method for use with bootstrap that will 5817987Speter * ensure that we never pass internal engine objects that should not be externally observable (currently ConsString and 591556Srgrimes * ScriptObject) to Java APIs, but rather that we flatten it into a String. We can't just add this functionality as 601556Srgrimes * custom converters via {@code GuaardingTypeConverterFactory}, since they are not consulted when 6125222Ssteve * the target method handle parameter signature is {@code Object}. This linker also makes sure that primitive 621556Srgrimes * {@link String} operations can be invoked on a {@link ConsString}, and allows invocation of objects implementing 6317987Speter * the {@link FunctionalInterface} attribute. 6417987Speter */ 6517987Speterpublic class NashornBeansLinker implements GuardingDynamicLinker { 661556Srgrimes // System property to control whether to wrap ScriptObject->ScriptObjectMirror for 671556Srgrimes // Object type arguments of Java method calls, field set and array set. 6817987Speter private static final boolean MIRROR_ALWAYS = Options.getBooleanProperty("nashorn.mirror.always", true); 6917987Speter 701556Srgrimes private static final MethodHandle EXPORT_ARGUMENT; 711556Srgrimes private static final MethodHandle IMPORT_RESULT; 721556Srgrimes private static final MethodHandle FILTER_CONSSTRING; 731556Srgrimes 741556Srgrimes static { 751556Srgrimes final Lookup lookup = new Lookup(MethodHandles.lookup()); 761556Srgrimes EXPORT_ARGUMENT = lookup.findOwnStatic("exportArgument", Object.class, Object.class); 771556Srgrimes IMPORT_RESULT = lookup.findOwnStatic("importResult", Object.class, Object.class); 781556Srgrimes FILTER_CONSSTRING = lookup.findOwnStatic("consStringFilter", Object.class, Object.class); 791556Srgrimes } 801556Srgrimes 811556Srgrimes // cache of @FunctionalInterface method of implementor classes 821556Srgrimes private static final ClassValue<Method> FUNCTIONAL_IFACE_METHOD = new ClassValue<Method>() { 831556Srgrimes @Override 841556Srgrimes protected Method computeValue(final Class<?> type) { 851556Srgrimes return findFunctionalInterfaceMethod(type); 8628346Ssteve } 871556Srgrimes }; 881556Srgrimes 8928346Ssteve private final BeansLinker beansLinker = new BeansLinker(); 901556Srgrimes 9138536Scracauer @Override 9238950Scracauer public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest, final LinkerServices linkerServices) throws Exception { 9338536Scracauer final Object self = linkRequest.getReceiver(); 941556Srgrimes final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor(); 9520425Ssteve if (self instanceof ConsString) { 9690111Simp // In order to treat ConsString like a java.lang.String we need a link request with a string receiver. 9720425Ssteve final Object[] arguments = linkRequest.getArguments(); 9890111Simp arguments[0] = ""; 9990111Simp final LinkRequest forgedLinkRequest = linkRequest.replaceArguments(desc, arguments); 10090111Simp final GuardedInvocation invocation = getGuardedInvocation(beansLinker, forgedLinkRequest, linkerServices); 10120425Ssteve // If an invocation is found we add a filter that makes it work for both Strings and ConsStrings. 10290111Simp return invocation == null ? null : invocation.filterArguments(0, FILTER_CONSSTRING); 10320425Ssteve } 10490111Simp 10590111Simp if (self != null && "call".equals(desc.getNameToken(CallSiteDescriptor.OPERATOR))) { 10690111Simp // Support dyn:call on any object that supports some @FunctionalInterface 1071556Srgrimes // annotated interface. This way Java method, constructor references or 1081556Srgrimes // implementations of java.util.function.* interfaces can be called as though 1091556Srgrimes // those are script functions. 1101556Srgrimes final Method m = getFunctionalInterfaceMethod(self.getClass()); 1111556Srgrimes if (m != null) { 1121556Srgrimes final MethodType callType = desc.getMethodType(); 1131556Srgrimes // 'callee' and 'thiz' passed from script + actual arguments 1141556Srgrimes if (callType.parameterCount() != m.getParameterCount() + 2) { 1151556Srgrimes throw typeError("no.method.matches.args", ScriptRuntime.safeToString(self)); 1161556Srgrimes } 1171556Srgrimes return new GuardedInvocation( 1181556Srgrimes // drop 'thiz' passed from the script. 11920425Ssteve MH.dropArguments(linkerServices.filterInternalObjects(desc.getLookup().unreflect(m)), 1, 1201556Srgrimes callType.parameterType(1)), Guards.getInstanceOfGuard( 12190111Simp m.getDeclaringClass())).asTypeSafeReturn( 12217987Speter new NashornBeansLinkerServices(linkerServices), callType); 1231556Srgrimes } 1241556Srgrimes } 1251556Srgrimes return getGuardedInvocation(beansLinker, linkRequest, linkerServices); 1261556Srgrimes } 1271556Srgrimes 1281556Srgrimes /** 1291556Srgrimes * Delegates to the specified linker but injects its linker services wrapper so that it will apply all special 1301556Srgrimes * conversions that this class does. 13120425Ssteve * @param delegateLinker the linker to which the actual work is delegated to. 1321556Srgrimes * @param linkRequest the delegated link request 13320425Ssteve * @param linkerServices the original link services that will be augmented with special conversions 13420425Ssteve * @return the guarded invocation from the delegate, possibly augmented with special conversions 13520425Ssteve * @throws Exception if the delegate throws an exception 13620425Ssteve */ 1371556Srgrimes public static GuardedInvocation getGuardedInvocation(final GuardingDynamicLinker delegateLinker, final LinkRequest linkRequest, final LinkerServices linkerServices) throws Exception { 1381556Srgrimes return delegateLinker.getGuardedInvocation(linkRequest, new NashornBeansLinkerServices(linkerServices)); 1391556Srgrimes } 1401556Srgrimes 1411556Srgrimes @SuppressWarnings("unused") 14217987Speter private static Object exportArgument(final Object arg) { 14317987Speter return exportArgument(arg, MIRROR_ALWAYS); 1441556Srgrimes } 1451556Srgrimes 1461556Srgrimes static Object exportArgument(final Object arg, final boolean mirrorAlways) { 1471556Srgrimes if (arg instanceof ConsString) { 1481556Srgrimes return arg.toString(); 1491556Srgrimes } else if (mirrorAlways && arg instanceof ScriptObject) { 1501556Srgrimes return ScriptUtils.wrap((ScriptObject)arg); 1511556Srgrimes } else { 1521556Srgrimes return arg; 1531556Srgrimes } 1541556Srgrimes } 1551556Srgrimes 1561556Srgrimes @SuppressWarnings("unused") 1571556Srgrimes private static Object importResult(final Object arg) { 15817987Speter return ScriptUtils.unwrap(arg); 15920425Ssteve } 1601556Srgrimes 16120425Ssteve @SuppressWarnings("unused") 16220425Ssteve private static Object consStringFilter(final Object arg) { 16320425Ssteve return arg instanceof ConsString ? arg.toString() : arg; 1641556Srgrimes } 16517987Speter 16620425Ssteve private static Method findFunctionalInterfaceMethod(final Class<?> clazz) { 1671556Srgrimes if (clazz == null) { 16820425Ssteve return null; 16920425Ssteve } 17020425Ssteve 1711556Srgrimes for (final Class<?> iface : clazz.getInterfaces()) { 1721556Srgrimes // check accessiblity up-front 1731556Srgrimes if (! Context.isAccessibleClass(iface)) { 1741556Srgrimes continue; 1751556Srgrimes } 1761556Srgrimes 17720425Ssteve // check for @FunctionalInterface 1781556Srgrimes if (iface.isAnnotationPresent(FunctionalInterface.class)) { 1791556Srgrimes // return the first abstract method 1801556Srgrimes for (final Method m : iface.getMethods()) { 18128346Ssteve if (Modifier.isAbstract(m.getModifiers())) { 18217987Speter return m; 1831556Srgrimes } 1841556Srgrimes } 1851556Srgrimes } 1861556Srgrimes } 1871556Srgrimes 1881556Srgrimes // did not find here, try super class 1891556Srgrimes return findFunctionalInterfaceMethod(clazz.getSuperclass()); 1901556Srgrimes } 1911556Srgrimes 1921556Srgrimes // Returns @FunctionalInterface annotated interface's single abstract 1931556Srgrimes // method. If not found, returns null. 1941556Srgrimes static Method getFunctionalInterfaceMethod(final Class<?> clazz) { 1951556Srgrimes return FUNCTIONAL_IFACE_METHOD.get(clazz); 19617987Speter } 19790111Simp 19817987Speter static MethodHandleTransformer createHiddenObjectFilter() { 1991556Srgrimes return new DefaultInternalObjectFilter(EXPORT_ARGUMENT, MIRROR_ALWAYS ? IMPORT_RESULT : null); 2001556Srgrimes } 2011556Srgrimes 2021556Srgrimes private static class NashornBeansLinkerServices implements LinkerServices { 2031556Srgrimes private final LinkerServices linkerServices; 2041556Srgrimes 2051556Srgrimes NashornBeansLinkerServices(final LinkerServices linkerServices) { 2061556Srgrimes this.linkerServices = linkerServices; 20720425Ssteve } 2081556Srgrimes 20920425Ssteve @Override 21020425Ssteve public MethodHandle asType(final MethodHandle handle, final MethodType fromType) { 21120425Ssteve return linkerServices.asType(handle, fromType); 2121556Srgrimes } 2131556Srgrimes 21445916Scracauer @Override 2151556Srgrimes public MethodHandle asTypeLosslessReturn(final MethodHandle handle, final MethodType fromType) { 2161556Srgrimes return Implementation.asTypeLosslessReturn(this, handle, fromType); 2171556Srgrimes } 2181556Srgrimes 2191556Srgrimes @Override 22017987Speter public MethodHandle getTypeConverter(final Class<?> sourceType, final Class<?> targetType) { 22190111Simp return linkerServices.getTypeConverter(sourceType, targetType); 22217987Speter } 2231556Srgrimes 2241556Srgrimes @Override 2251556Srgrimes public boolean canConvert(final Class<?> from, final Class<?> to) { 2261556Srgrimes return linkerServices.canConvert(from, to); 2271556Srgrimes } 2281556Srgrimes 2291556Srgrimes @Override 2301556Srgrimes public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest) throws Exception { 2311556Srgrimes return linkerServices.getGuardedInvocation(linkRequest); 2321556Srgrimes } 2331556Srgrimes 2341556Srgrimes @Override 2351556Srgrimes public Comparison compareConversion(final Class<?> sourceType, final Class<?> targetType1, final Class<?> targetType2) { 23690111Simp if (sourceType == ConsString.class) { 23717987Speter if (String.class == targetType1 || CharSequence.class == targetType1) { 2381556Srgrimes return Comparison.TYPE_1_BETTER; 2391556Srgrimes } 2401556Srgrimes 2411556Srgrimes if (String.class == targetType2 || CharSequence.class == targetType2) { 2421556Srgrimes return Comparison.TYPE_2_BETTER; 2431556Srgrimes } 2441556Srgrimes } 2451556Srgrimes return linkerServices.compareConversion(sourceType, targetType1, targetType2); 24626104Ssteve } 2471556Srgrimes 2481556Srgrimes @Override 2491556Srgrimes public MethodHandle filterInternalObjects(MethodHandle target) { 2501556Srgrimes return linkerServices.filterInternalObjects(target); 2511556Srgrimes } 2521556Srgrimes } 2531556Srgrimes} 2541556Srgrimes