NashornBeansLinker.java revision 1483:7cb19fa78763
11541Srgrimes/* 21541Srgrimes * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. 31541Srgrimes * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 41541Srgrimes * 51541Srgrimes * This code is free software; you can redistribute it and/or modify it 61541Srgrimes * under the terms of the GNU General Public License version 2 only, as 71541Srgrimes * published by the Free Software Foundation. Oracle designates this 81541Srgrimes * particular file as subject to the "Classpath" exception as provided 91541Srgrimes * by Oracle in the LICENSE file that accompanied this code. 101541Srgrimes * 111541Srgrimes * This code is distributed in the hope that it will be useful, but WITHOUT 121541Srgrimes * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 131541Srgrimes * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 141541Srgrimes * version 2 for more details (a copy is included in the LICENSE file that 151541Srgrimes * accompanied this code). 161541Srgrimes * 171541Srgrimes * You should have received a copy of the GNU General Public License version 181541Srgrimes * 2 along with this work; if not, write to the Free Software Foundation, 191541Srgrimes * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 201541Srgrimes * 211541Srgrimes * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 221541Srgrimes * or visit www.oracle.com if you need additional information or have any 231541Srgrimes * questions. 241541Srgrimes */ 251541Srgrimes 261541Srgrimespackage jdk.nashorn.internal.runtime.linker; 271541Srgrimes 281541Srgrimesimport static jdk.nashorn.internal.lookup.Lookup.MH; 2985052Sru 3050477Speterimport java.lang.invoke.MethodHandle; 311541Srgrimesimport java.lang.invoke.MethodHandles; 321541Srgrimesimport java.lang.invoke.MethodType; 332168Spaulimport java.lang.reflect.Method; 342168Spaulimport java.lang.reflect.Modifier; 352168Spaulimport jdk.internal.dynalink.CallSiteDescriptor; 361541Srgrimesimport jdk.internal.dynalink.NamedOperation; 371541Srgrimesimport jdk.internal.dynalink.StandardOperation; 388876Srgrimesimport jdk.internal.dynalink.beans.BeansLinker; 391541Srgrimesimport jdk.internal.dynalink.linker.ConversionComparator.Comparison; 401541Srgrimesimport jdk.internal.dynalink.linker.GuardedInvocation; 411541Srgrimesimport jdk.internal.dynalink.linker.GuardingDynamicLinker; 421541Srgrimesimport jdk.internal.dynalink.linker.LinkRequest; 431541Srgrimesimport jdk.internal.dynalink.linker.LinkerServices; 441541Srgrimesimport jdk.internal.dynalink.linker.MethodHandleTransformer; 451541Srgrimesimport jdk.internal.dynalink.linker.support.DefaultInternalObjectFilter; 461541Srgrimesimport jdk.internal.dynalink.linker.support.Lookup; 471541Srgrimesimport jdk.nashorn.api.scripting.ScriptUtils; 481541Srgrimesimport jdk.nashorn.internal.runtime.ConsString; 491541Srgrimesimport jdk.nashorn.internal.runtime.Context; 501541Srgrimesimport jdk.nashorn.internal.runtime.ScriptObject; 511541Srgrimesimport jdk.nashorn.internal.runtime.options.Options; 521541Srgrimes 531541Srgrimes/** 541541Srgrimes * This linker delegates to a {@code BeansLinker} but passes it a special linker services object that has a modified 551541Srgrimes * {@code compareConversion} method that favors conversion of {@link ConsString} to either {@link String} or 561541Srgrimes * {@link CharSequence}. It also provides a {@link #createHiddenObjectFilter()} method for use with bootstrap that will 57122922Sandre * ensure that we never pass internal engine objects that should not be externally observable (currently ConsString and 58122922Sandre * ScriptObject) to Java APIs, but rather that we flatten it into a String. We can't just add this functionality as 59122922Sandre * custom converters via {@code GuaardingTypeConverterFactory}, since they are not consulted when 60122922Sandre * the target method handle parameter signature is {@code Object}. This linker also makes sure that primitive 61122922Sandre * {@link String} operations can be invoked on a {@link ConsString}, and allows invocation of objects implementing 62122922Sandre * the {@link FunctionalInterface} attribute. 631541Srgrimes */ 641541Srgrimespublic class NashornBeansLinker implements GuardingDynamicLinker { 651541Srgrimes // System property to control whether to wrap ScriptObject->ScriptObjectMirror for 661541Srgrimes // Object type arguments of Java method calls, field set and array set. 671541Srgrimes private static final boolean MIRROR_ALWAYS = Options.getBooleanProperty("nashorn.mirror.always", true); 6813765Smpp 6913765Smpp private static final MethodHandle EXPORT_ARGUMENT; 701541Srgrimes private static final MethodHandle IMPORT_RESULT; 711541Srgrimes private static final MethodHandle FILTER_CONSSTRING; 721541Srgrimes 731541Srgrimes static { 745791Swollman final Lookup lookup = new Lookup(MethodHandles.lookup()); 751541Srgrimes EXPORT_ARGUMENT = lookup.findOwnStatic("exportArgument", Object.class, Object.class); 761541Srgrimes IMPORT_RESULT = lookup.findOwnStatic("importResult", Object.class, Object.class); 771541Srgrimes FILTER_CONSSTRING = lookup.findOwnStatic("consStringFilter", Object.class, Object.class); 781541Srgrimes } 791541Srgrimes 801541Srgrimes // cache of @FunctionalInterface method of implementor classes 811541Srgrimes private static final ClassValue<String> FUNCTIONAL_IFACE_METHOD_NAME = new ClassValue<String>() { 821541Srgrimes @Override 831541Srgrimes protected String computeValue(final Class<?> type) { 841541Srgrimes return findFunctionalInterfaceMethodName(type); 851541Srgrimes } 865833Sbde }; 875833Sbde 885833Sbde private final BeansLinker beansLinker = new BeansLinker(); 895833Sbde 905833Sbde @Override 911541Srgrimes public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest, final LinkerServices linkerServices) throws Exception { 921541Srgrimes final Object self = linkRequest.getReceiver(); 931541Srgrimes final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor(); 941541Srgrimes if (self instanceof ConsString) { 951541Srgrimes // In order to treat ConsString like a java.lang.String we need a link request with a string receiver. 961541Srgrimes final Object[] arguments = linkRequest.getArguments(); 971541Srgrimes arguments[0] = ""; 981541Srgrimes final LinkRequest forgedLinkRequest = linkRequest.replaceArguments(desc, arguments); 991541Srgrimes final GuardedInvocation invocation = getGuardedInvocation(beansLinker, forgedLinkRequest, linkerServices); 1001541Srgrimes // If an invocation is found we add a filter that makes it work for both Strings and ConsStrings. 1011541Srgrimes return invocation == null ? null : invocation.filterArguments(0, FILTER_CONSSTRING); 1021541Srgrimes } 103128454Sluigi 104128454Sluigi if (self != null && NamedOperation.getBaseOperation(desc.getOperation()) == StandardOperation.CALL) { 105128454Sluigi // Support CALL on any object that supports some @FunctionalInterface 106128454Sluigi // annotated interface. This way Java method, constructor references or 107128454Sluigi // implementations of java.util.function.* interfaces can be called as though 1081541Srgrimes // those are script functions. 1091541Srgrimes final String name = getFunctionalInterfaceMethodName(self.getClass()); 1101541Srgrimes if (name != null) { 1117197Swollman final MethodType callType = desc.getMethodType(); 1121541Srgrimes // drop callee (Undefined ScriptFunction) and change the request to be CALL_METHOD:<name> 113122922Sandre final CallSiteDescriptor newDesc = new CallSiteDescriptor( 114127828Sluigi NashornCallSiteDescriptor.getLookupInternal(desc), 115127828Sluigi new NamedOperation(StandardOperation.CALL_METHOD, name), 1161541Srgrimes desc.getMethodType().dropParameterTypes(1, 2)); 1171541Srgrimes final GuardedInvocation gi = getGuardedInvocation(beansLinker, 1181541Srgrimes linkRequest.replaceArguments(newDesc, linkRequest.getArguments()), 1195791Swollman new NashornBeansLinkerServices(linkerServices)); 120120727Ssam 121120727Ssam // drop 'thiz' passed from the script. 122120727Ssam return gi.replaceMethods( 123120727Ssam MH.dropArguments(linkerServices.filterInternalObjects(gi.getInvocation()), 1, callType.parameterType(1)), 1241541Srgrimes gi.getGuard()); 1251541Srgrimes } 1261541Srgrimes } 1271541Srgrimes return getGuardedInvocation(beansLinker, linkRequest, linkerServices); 1281541Srgrimes } 1291541Srgrimes 1301541Srgrimes /** 1311541Srgrimes * Delegates to the specified linker but injects its linker services wrapper so that it will apply all special 1321541Srgrimes * conversions that this class does. 1331541Srgrimes * @param delegateLinker the linker to which the actual work is delegated to. 1341541Srgrimes * @param linkRequest the delegated link request 1351541Srgrimes * @param linkerServices the original link services that will be augmented with special conversions 1361541Srgrimes * @return the guarded invocation from the delegate, possibly augmented with special conversions 1371541Srgrimes * @throws Exception if the delegate throws an exception 1381541Srgrimes */ 1391541Srgrimes public static GuardedInvocation getGuardedInvocation(final GuardingDynamicLinker delegateLinker, final LinkRequest linkRequest, final LinkerServices linkerServices) throws Exception { 1404104Swollman return delegateLinker.getGuardedInvocation(linkRequest, new NashornBeansLinkerServices(linkerServices)); 1414104Swollman } 1421541Srgrimes 1431541Srgrimes @SuppressWarnings("unused") 1441541Srgrimes private static Object exportArgument(final Object arg) { 1451541Srgrimes return exportArgument(arg, MIRROR_ALWAYS); 1461541Srgrimes } 1471541Srgrimes 1481541Srgrimes static Object exportArgument(final Object arg, final boolean mirrorAlways) { 14986764Sjlemon if (arg instanceof ConsString) { 1501541Srgrimes return arg.toString(); 1511541Srgrimes } else if (mirrorAlways && arg instanceof ScriptObject) { 15217835Sjulian return ScriptUtils.wrap((ScriptObject)arg); 1531541Srgrimes } else { 1541541Srgrimes return arg; 1551541Srgrimes } 1561541Srgrimes } 1571541Srgrimes 158122921Sandre @SuppressWarnings("unused") 159122921Sandre private static Object importResult(final Object arg) { 160122921Sandre return ScriptUtils.unwrap(arg); 161122921Sandre } 162122921Sandre 1635099Swollman @SuppressWarnings("unused") 1645099Swollman private static Object consStringFilter(final Object arg) { 16518839Swollman return arg instanceof ConsString ? arg.toString() : arg; 1666245Swollman } 16715652Swollman 16815652Swollman private static String findFunctionalInterfaceMethodName(final Class<?> clazz) { 16915652Swollman if (clazz == null) { 17015652Swollman return null; 1711541Srgrimes } 1721541Srgrimes 1731541Srgrimes for (final Class<?> iface : clazz.getInterfaces()) { 1741541Srgrimes // check accessibility up-front 1751541Srgrimes if (! Context.isAccessibleClass(iface)) { 1761541Srgrimes continue; 1771541Srgrimes } 1781541Srgrimes 1791541Srgrimes // check for @FunctionalInterface 1801541Srgrimes if (iface.isAnnotationPresent(FunctionalInterface.class)) { 1811541Srgrimes // return the first abstract method 1821541Srgrimes for (final Method m : iface.getMethods()) { 1831541Srgrimes if (Modifier.isAbstract(m.getModifiers())) { 1841541Srgrimes return m.getName(); 1851541Srgrimes } 1861541Srgrimes } 1871541Srgrimes } 1881541Srgrimes } 1891541Srgrimes 1901541Srgrimes // did not find here, try super class 1911541Srgrimes return findFunctionalInterfaceMethodName(clazz.getSuperclass()); 1921541Srgrimes } 1931541Srgrimes 1941541Srgrimes // Returns @FunctionalInterface annotated interface's single abstract 1951541Srgrimes // method name. If not found, returns null. 1961541Srgrimes static String getFunctionalInterfaceMethodName(final Class<?> clazz) { 1971541Srgrimes return FUNCTIONAL_IFACE_METHOD_NAME.get(clazz); 1981541Srgrimes } 1991541Srgrimes 2005791Swollman static MethodHandleTransformer createHiddenObjectFilter() { 2011541Srgrimes return new DefaultInternalObjectFilter(EXPORT_ARGUMENT, MIRROR_ALWAYS ? IMPORT_RESULT : null); 20251252Sru } 20351252Sru 20451252Sru private static class NashornBeansLinkerServices implements LinkerServices { 2051541Srgrimes private final LinkerServices linkerServices; 2061541Srgrimes 2071541Srgrimes NashornBeansLinkerServices(final LinkerServices linkerServices) { 2081541Srgrimes this.linkerServices = linkerServices; 2091541Srgrimes } 2101541Srgrimes 2111541Srgrimes @Override 2121541Srgrimes public MethodHandle asType(final MethodHandle handle, final MethodType fromType) { 2131541Srgrimes return linkerServices.asType(handle, fromType); 2141541Srgrimes } 2151541Srgrimes 2161541Srgrimes @Override 2171541Srgrimes public MethodHandle getTypeConverter(final Class<?> sourceType, final Class<?> targetType) { 2181541Srgrimes return linkerServices.getTypeConverter(sourceType, targetType); 21921666Swollman } 22021666Swollman 22189498Sru @Override 2221541Srgrimes public boolean canConvert(final Class<?> from, final Class<?> to) { 22351252Sru return linkerServices.canConvert(from, to); 22451252Sru } 22551252Sru 2261541Srgrimes @Override 2271541Srgrimes public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest) throws Exception { 22851252Sru return linkerServices.getGuardedInvocation(linkRequest); 2291541Srgrimes } 2301541Srgrimes 2311541Srgrimes @Override 2321541Srgrimes public Comparison compareConversion(final Class<?> sourceType, final Class<?> targetType1, final Class<?> targetType2) { 2331541Srgrimes if (sourceType == ConsString.class) { 2341541Srgrimes if (String.class == targetType1 || CharSequence.class == targetType1) { 2351541Srgrimes return Comparison.TYPE_1_BETTER; 23651252Sru } 2371541Srgrimes 2381541Srgrimes if (String.class == targetType2 || CharSequence.class == targetType2) { 2391541Srgrimes return Comparison.TYPE_2_BETTER; 2401541Srgrimes } 2411541Srgrimes } 2421541Srgrimes return linkerServices.compareConversion(sourceType, targetType1, targetType2); 2431541Srgrimes } 2441541Srgrimes 2451541Srgrimes @Override 2461541Srgrimes public MethodHandle filterInternalObjects(final MethodHandle target) { 2471541Srgrimes return linkerServices.filterInternalObjects(target); 2481541Srgrimes } 2491541Srgrimes } 2501541Srgrimes} 2511541Srgrimes