rt/emul/compact/src/main/java/java/lang/invoke/AbstractValidatingLambdaMetafactory.java
1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/rt/emul/compact/src/main/java/java/lang/invoke/AbstractValidatingLambdaMetafactory.java Sat Aug 09 11:11:13 2014 +0200
1.3 @@ -0,0 +1,375 @@
1.4 +/*
1.5 + * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Oracle designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Oracle in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.25 + * or visit www.oracle.com if you need additional information or have any
1.26 + * questions.
1.27 + */
1.28 +package java.lang.invoke;
1.29 +
1.30 +import sun.invoke.util.Wrapper;
1.31 +
1.32 +import static sun.invoke.util.Wrapper.forPrimitiveType;
1.33 +import static sun.invoke.util.Wrapper.forWrapperType;
1.34 +import static sun.invoke.util.Wrapper.isWrapperType;
1.35 +
1.36 +/**
1.37 + * Abstract implementation of a lambda metafactory which provides parameter
1.38 + * unrolling and input validation.
1.39 + *
1.40 + * @see LambdaMetafactory
1.41 + */
1.42 +/* package */ abstract class AbstractValidatingLambdaMetafactory {
1.43 +
1.44 + /*
1.45 + * For context, the comments for the following fields are marked in quotes
1.46 + * with their values, given this program:
1.47 + * interface II<T> { Object foo(T x); }
1.48 + * interface JJ<R extends Number> extends II<R> { }
1.49 + * class CC { String impl(int i) { return "impl:"+i; }}
1.50 + * class X {
1.51 + * public static void main(String[] args) {
1.52 + * JJ<Integer> iii = (new CC())::impl;
1.53 + * System.out.printf(">>> %s\n", iii.foo(44));
1.54 + * }}
1.55 + */
1.56 + final Class<?> targetClass; // The class calling the meta-factory via invokedynamic "class X"
1.57 + final MethodType invokedType; // The type of the invoked method "(CC)II"
1.58 + final Class<?> samBase; // The type of the returned instance "interface JJ"
1.59 + final String samMethodName; // Name of the SAM method "foo"
1.60 + final MethodType samMethodType; // Type of the SAM method "(Object)Object"
1.61 + final MethodHandle implMethod; // Raw method handle for the implementation method
1.62 + final MethodHandleInfo implInfo; // Info about the implementation method handle "MethodHandleInfo[5 CC.impl(int)String]"
1.63 + final int implKind; // Invocation kind for implementation "5"=invokevirtual
1.64 + final boolean implIsInstanceMethod; // Is the implementation an instance method "true"
1.65 + final Class<?> implDefiningClass; // Type defining the implementation "class CC"
1.66 + final MethodType implMethodType; // Type of the implementation method "(int)String"
1.67 + final MethodType instantiatedMethodType; // Instantiated erased functional interface method type "(Integer)Object"
1.68 + final boolean isSerializable; // Should the returned instance be serializable
1.69 + final Class<?>[] markerInterfaces; // Additional marker interfaces to be implemented
1.70 + final MethodType[] additionalBridges; // Signatures of additional methods to bridge
1.71 +
1.72 +
1.73 + /**
1.74 + * Meta-factory constructor.
1.75 + *
1.76 + * @param caller Stacked automatically by VM; represents a lookup context
1.77 + * with the accessibility privileges of the caller.
1.78 + * @param invokedType Stacked automatically by VM; the signature of the
1.79 + * invoked method, which includes the expected static
1.80 + * type of the returned lambda object, and the static
1.81 + * types of the captured arguments for the lambda. In
1.82 + * the event that the implementation method is an
1.83 + * instance method, the first argument in the invocation
1.84 + * signature will correspond to the receiver.
1.85 + * @param samMethodName Name of the method in the functional interface to
1.86 + * which the lambda or method reference is being
1.87 + * converted, represented as a String.
1.88 + * @param samMethodType Type of the method in the functional interface to
1.89 + * which the lambda or method reference is being
1.90 + * converted, represented as a MethodType.
1.91 + * @param implMethod The implementation method which should be called
1.92 + * (with suitable adaptation of argument types, return
1.93 + * types, and adjustment for captured arguments) when
1.94 + * methods of the resulting functional interface instance
1.95 + * are invoked.
1.96 + * @param instantiatedMethodType The signature of the primary functional
1.97 + * interface method after type variables are
1.98 + * substituted with their instantiation from
1.99 + * the capture site
1.100 + * @param isSerializable Should the lambda be made serializable? If set,
1.101 + * either the target type or one of the additional SAM
1.102 + * types must extend {@code Serializable}.
1.103 + * @param markerInterfaces Additional interfaces which the lambda object
1.104 + * should implement.
1.105 + * @param additionalBridges Method types for additional signatures to be
1.106 + * bridged to the implementation method
1.107 + * @throws LambdaConversionException If any of the meta-factory protocol
1.108 + * invariants are violated
1.109 + */
1.110 + AbstractValidatingLambdaMetafactory(MethodHandles.Lookup caller,
1.111 + MethodType invokedType,
1.112 + String samMethodName,
1.113 + MethodType samMethodType,
1.114 + MethodHandle implMethod,
1.115 + MethodType instantiatedMethodType,
1.116 + boolean isSerializable,
1.117 + Class<?>[] markerInterfaces,
1.118 + MethodType[] additionalBridges)
1.119 + throws LambdaConversionException {
1.120 + if ((caller.lookupModes() & MethodHandles.Lookup.PRIVATE) == 0) {
1.121 + throw new LambdaConversionException(String.format(
1.122 + "Invalid caller: %s",
1.123 + caller.lookupClass().getName()));
1.124 + }
1.125 + this.targetClass = caller.lookupClass();
1.126 + this.invokedType = invokedType;
1.127 +
1.128 + this.samBase = invokedType.returnType();
1.129 +
1.130 + this.samMethodName = samMethodName;
1.131 + this.samMethodType = samMethodType;
1.132 +
1.133 + this.implMethod = implMethod;
1.134 + this.implInfo = caller.revealDirect(implMethod);
1.135 + this.implKind = implInfo.getReferenceKind();
1.136 + this.implIsInstanceMethod =
1.137 + implKind == MethodHandleInfo.REF_invokeVirtual ||
1.138 + implKind == MethodHandleInfo.REF_invokeSpecial ||
1.139 + implKind == MethodHandleInfo.REF_invokeInterface;
1.140 + this.implDefiningClass = implInfo.getDeclaringClass();
1.141 + this.implMethodType = implInfo.getMethodType();
1.142 + this.instantiatedMethodType = instantiatedMethodType;
1.143 + this.isSerializable = isSerializable;
1.144 + this.markerInterfaces = markerInterfaces;
1.145 + this.additionalBridges = additionalBridges;
1.146 +
1.147 + if (!samBase.isInterface()) {
1.148 + throw new LambdaConversionException(String.format(
1.149 + "Functional interface %s is not an interface",
1.150 + samBase.getName()));
1.151 + }
1.152 +
1.153 + for (Class<?> c : markerInterfaces) {
1.154 + if (!c.isInterface()) {
1.155 + throw new LambdaConversionException(String.format(
1.156 + "Marker interface %s is not an interface",
1.157 + c.getName()));
1.158 + }
1.159 + }
1.160 + }
1.161 +
1.162 + /**
1.163 + * Build the CallSite.
1.164 + *
1.165 + * @return a CallSite, which, when invoked, will return an instance of the
1.166 + * functional interface
1.167 + * @throws ReflectiveOperationException
1.168 + */
1.169 + abstract CallSite buildCallSite()
1.170 + throws LambdaConversionException;
1.171 +
1.172 + /**
1.173 + * Check the meta-factory arguments for errors
1.174 + * @throws LambdaConversionException if there are improper conversions
1.175 + */
1.176 + void validateMetafactoryArgs() throws LambdaConversionException {
1.177 + switch (implKind) {
1.178 + case MethodHandleInfo.REF_invokeInterface:
1.179 + case MethodHandleInfo.REF_invokeVirtual:
1.180 + case MethodHandleInfo.REF_invokeStatic:
1.181 + case MethodHandleInfo.REF_newInvokeSpecial:
1.182 + case MethodHandleInfo.REF_invokeSpecial:
1.183 + break;
1.184 + default:
1.185 + throw new LambdaConversionException(String.format("Unsupported MethodHandle kind: %s", implInfo));
1.186 + }
1.187 +
1.188 + // Check arity: optional-receiver + captured + SAM == impl
1.189 + final int implArity = implMethodType.parameterCount();
1.190 + final int receiverArity = implIsInstanceMethod ? 1 : 0;
1.191 + final int capturedArity = invokedType.parameterCount();
1.192 + final int samArity = samMethodType.parameterCount();
1.193 + final int instantiatedArity = instantiatedMethodType.parameterCount();
1.194 + if (implArity + receiverArity != capturedArity + samArity) {
1.195 + throw new LambdaConversionException(
1.196 + String.format("Incorrect number of parameters for %s method %s; %d captured parameters, %d functional interface method parameters, %d implementation parameters",
1.197 + implIsInstanceMethod ? "instance" : "static", implInfo,
1.198 + capturedArity, samArity, implArity));
1.199 + }
1.200 + if (instantiatedArity != samArity) {
1.201 + throw new LambdaConversionException(
1.202 + String.format("Incorrect number of parameters for %s method %s; %d instantiated parameters, %d functional interface method parameters",
1.203 + implIsInstanceMethod ? "instance" : "static", implInfo,
1.204 + instantiatedArity, samArity));
1.205 + }
1.206 + for (MethodType bridgeMT : additionalBridges) {
1.207 + if (bridgeMT.parameterCount() != samArity) {
1.208 + throw new LambdaConversionException(
1.209 + String.format("Incorrect number of parameters for bridge signature %s; incompatible with %s",
1.210 + bridgeMT, samMethodType));
1.211 + }
1.212 + }
1.213 +
1.214 + // If instance: first captured arg (receiver) must be subtype of class where impl method is defined
1.215 + final int capturedStart;
1.216 + final int samStart;
1.217 + if (implIsInstanceMethod) {
1.218 + final Class<?> receiverClass;
1.219 +
1.220 + // implementation is an instance method, adjust for receiver in captured variables / SAM arguments
1.221 + if (capturedArity == 0) {
1.222 + // receiver is function parameter
1.223 + capturedStart = 0;
1.224 + samStart = 1;
1.225 + receiverClass = instantiatedMethodType.parameterType(0);
1.226 + } else {
1.227 + // receiver is a captured variable
1.228 + capturedStart = 1;
1.229 + samStart = 0;
1.230 + receiverClass = invokedType.parameterType(0);
1.231 + }
1.232 +
1.233 + // check receiver type
1.234 + if (!implDefiningClass.isAssignableFrom(receiverClass)) {
1.235 + throw new LambdaConversionException(
1.236 + String.format("Invalid receiver type %s; not a subtype of implementation type %s",
1.237 + receiverClass, implDefiningClass));
1.238 + }
1.239 +
1.240 + Class<?> implReceiverClass = implMethod.type().parameterType(0);
1.241 + if (implReceiverClass != implDefiningClass && !implReceiverClass.isAssignableFrom(receiverClass)) {
1.242 + throw new LambdaConversionException(
1.243 + String.format("Invalid receiver type %s; not a subtype of implementation receiver type %s",
1.244 + receiverClass, implReceiverClass));
1.245 + }
1.246 + } else {
1.247 + // no receiver
1.248 + capturedStart = 0;
1.249 + samStart = 0;
1.250 + }
1.251 +
1.252 + // Check for exact match on non-receiver captured arguments
1.253 + final int implFromCaptured = capturedArity - capturedStart;
1.254 + for (int i=0; i<implFromCaptured; i++) {
1.255 + Class<?> implParamType = implMethodType.parameterType(i);
1.256 + Class<?> capturedParamType = invokedType.parameterType(i + capturedStart);
1.257 + if (!capturedParamType.equals(implParamType)) {
1.258 + throw new LambdaConversionException(
1.259 + String.format("Type mismatch in captured lambda parameter %d: expecting %s, found %s",
1.260 + i, capturedParamType, implParamType));
1.261 + }
1.262 + }
1.263 + // Check for adaptation match on SAM arguments
1.264 + final int samOffset = samStart - implFromCaptured;
1.265 + for (int i=implFromCaptured; i<implArity; i++) {
1.266 + Class<?> implParamType = implMethodType.parameterType(i);
1.267 + Class<?> instantiatedParamType = instantiatedMethodType.parameterType(i + samOffset);
1.268 + if (!isAdaptableTo(instantiatedParamType, implParamType, true)) {
1.269 + throw new LambdaConversionException(
1.270 + String.format("Type mismatch for lambda argument %d: %s is not convertible to %s",
1.271 + i, instantiatedParamType, implParamType));
1.272 + }
1.273 + }
1.274 +
1.275 + // Adaptation match: return type
1.276 + Class<?> expectedType = instantiatedMethodType.returnType();
1.277 + Class<?> actualReturnType =
1.278 + (implKind == MethodHandleInfo.REF_newInvokeSpecial)
1.279 + ? implDefiningClass
1.280 + : implMethodType.returnType();
1.281 + Class<?> samReturnType = samMethodType.returnType();
1.282 + if (!isAdaptableToAsReturn(actualReturnType, expectedType)) {
1.283 + throw new LambdaConversionException(
1.284 + String.format("Type mismatch for lambda return: %s is not convertible to %s",
1.285 + actualReturnType, expectedType));
1.286 + }
1.287 + if (!isAdaptableToAsReturnStrict(expectedType, samReturnType)) {
1.288 + throw new LambdaConversionException(
1.289 + String.format("Type mismatch for lambda expected return: %s is not convertible to %s",
1.290 + expectedType, samReturnType));
1.291 + }
1.292 + for (MethodType bridgeMT : additionalBridges) {
1.293 + if (!isAdaptableToAsReturnStrict(expectedType, bridgeMT.returnType())) {
1.294 + throw new LambdaConversionException(
1.295 + String.format("Type mismatch for lambda expected return: %s is not convertible to %s",
1.296 + expectedType, bridgeMT.returnType()));
1.297 + }
1.298 + }
1.299 + }
1.300 +
1.301 + /**
1.302 + * Check type adaptability for parameter types.
1.303 + * @param fromType Type to convert from
1.304 + * @param toType Type to convert to
1.305 + * @param strict If true, do strict checks, else allow that fromType may be parameterized
1.306 + * @return True if 'fromType' can be passed to an argument of 'toType'
1.307 + */
1.308 + private boolean isAdaptableTo(Class<?> fromType, Class<?> toType, boolean strict) {
1.309 + if (fromType.equals(toType)) {
1.310 + return true;
1.311 + }
1.312 + if (fromType.isPrimitive()) {
1.313 + Wrapper wfrom = forPrimitiveType(fromType);
1.314 + if (toType.isPrimitive()) {
1.315 + // both are primitive: widening
1.316 + Wrapper wto = forPrimitiveType(toType);
1.317 + return wto.isConvertibleFrom(wfrom);
1.318 + } else {
1.319 + // from primitive to reference: boxing
1.320 + return toType.isAssignableFrom(wfrom.wrapperType());
1.321 + }
1.322 + } else {
1.323 + if (toType.isPrimitive()) {
1.324 + // from reference to primitive: unboxing
1.325 + Wrapper wfrom;
1.326 + if (isWrapperType(fromType) && (wfrom = forWrapperType(fromType)).primitiveType().isPrimitive()) {
1.327 + // fromType is a primitive wrapper; unbox+widen
1.328 + Wrapper wto = forPrimitiveType(toType);
1.329 + return wto.isConvertibleFrom(wfrom);
1.330 + } else {
1.331 + // must be convertible to primitive
1.332 + return !strict;
1.333 + }
1.334 + } else {
1.335 + // both are reference types: fromType should be a superclass of toType.
1.336 + return !strict || toType.isAssignableFrom(fromType);
1.337 + }
1.338 + }
1.339 + }
1.340 +
1.341 + /**
1.342 + * Check type adaptability for return types --
1.343 + * special handling of void type) and parameterized fromType
1.344 + * @return True if 'fromType' can be converted to 'toType'
1.345 + */
1.346 + private boolean isAdaptableToAsReturn(Class<?> fromType, Class<?> toType) {
1.347 + return toType.equals(void.class)
1.348 + || !fromType.equals(void.class) && isAdaptableTo(fromType, toType, false);
1.349 + }
1.350 + private boolean isAdaptableToAsReturnStrict(Class<?> fromType, Class<?> toType) {
1.351 + if (fromType.equals(void.class)) return toType.equals(void.class);
1.352 + return isAdaptableTo(fromType, toType, true);
1.353 + }
1.354 +
1.355 +
1.356 + /*********** Logging support -- for debugging only, uncomment as needed
1.357 + static final Executor logPool = Executors.newSingleThreadExecutor();
1.358 + protected static void log(final String s) {
1.359 + MethodHandleProxyLambdaMetafactory.logPool.execute(new Runnable() {
1.360 + @Override
1.361 + public void run() {
1.362 + System.out.println(s);
1.363 + }
1.364 + });
1.365 + }
1.366 +
1.367 + protected static void log(final String s, final Throwable e) {
1.368 + MethodHandleProxyLambdaMetafactory.logPool.execute(new Runnable() {
1.369 + @Override
1.370 + public void run() {
1.371 + System.out.println(s);
1.372 + e.printStackTrace(System.out);
1.373 + }
1.374 + });
1.375 + }
1.376 + ***********************/
1.377 +
1.378 +}