1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/classes/com/sun/tools/javac/comp/LambdaToMethod.java Mon Oct 29 10:39:49 2012 -0700
1.3 @@ -0,0 +1,1398 @@
1.4 +/*
1.5 + * Copyright (c) 2010, 2012, 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 com.sun.tools.javac.comp;
1.29 +
1.30 +import com.sun.tools.javac.tree.*;
1.31 +import com.sun.tools.javac.tree.JCTree;
1.32 +import com.sun.tools.javac.tree.JCTree.*;
1.33 +import com.sun.tools.javac.tree.JCTree.JCMemberReference.ReferenceKind;
1.34 +import com.sun.tools.javac.tree.TreeMaker;
1.35 +import com.sun.tools.javac.tree.TreeScanner;
1.36 +import com.sun.tools.javac.tree.TreeTranslator;
1.37 +import com.sun.tools.javac.code.Flags;
1.38 +import com.sun.tools.javac.code.Kinds;
1.39 +import com.sun.tools.javac.code.Symbol;
1.40 +import com.sun.tools.javac.code.Symbol.ClassSymbol;
1.41 +import com.sun.tools.javac.code.Symbol.DynamicMethodSymbol;
1.42 +import com.sun.tools.javac.code.Symbol.MethodSymbol;
1.43 +import com.sun.tools.javac.code.Symbol.VarSymbol;
1.44 +import com.sun.tools.javac.code.Symtab;
1.45 +import com.sun.tools.javac.code.Type;
1.46 +import com.sun.tools.javac.code.Type.ClassType;
1.47 +import com.sun.tools.javac.code.Type.MethodType;
1.48 +import com.sun.tools.javac.code.Types;
1.49 +import com.sun.tools.javac.comp.LambdaToMethod.LambdaAnalyzer.*;
1.50 +import com.sun.tools.javac.jvm.*;
1.51 +import com.sun.tools.javac.util.*;
1.52 +import com.sun.tools.javac.util.List;
1.53 +import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
1.54 +import com.sun.source.tree.MemberReferenceTree.ReferenceMode;
1.55 +
1.56 +import java.util.HashMap;
1.57 +import java.util.LinkedHashMap;
1.58 +import java.util.Map;
1.59 +
1.60 +import static com.sun.tools.javac.comp.LambdaToMethod.LambdaSymbolKind.*;
1.61 +import static com.sun.tools.javac.code.Flags.*;
1.62 +import static com.sun.tools.javac.code.Kinds.*;
1.63 +import static com.sun.tools.javac.code.TypeTag.BOT;
1.64 +import static com.sun.tools.javac.code.TypeTag.NONE;
1.65 +import static com.sun.tools.javac.code.TypeTag.VOID;
1.66 +import static com.sun.tools.javac.tree.JCTree.Tag.*;
1.67 +
1.68 +/**
1.69 + * This pass desugars lambda expressions into static methods
1.70 + *
1.71 + * <p><b>This is NOT part of any supported API.
1.72 + * If you write code that depends on this, you do so at your own risk.
1.73 + * This code and its internal interfaces are subject to change or
1.74 + * deletion without notice.</b>
1.75 + */
1.76 +public class LambdaToMethod extends TreeTranslator {
1.77 +
1.78 + private Names names;
1.79 + private Symtab syms;
1.80 + private Resolve rs;
1.81 + private TreeMaker make;
1.82 + private Types types;
1.83 + private TransTypes transTypes;
1.84 + private Env<AttrContext> attrEnv;
1.85 +
1.86 + /** the analyzer scanner */
1.87 + private LambdaAnalyzer analyzer;
1.88 +
1.89 + /** map from lambda trees to translation contexts */
1.90 + private Map<JCTree, TranslationContext<?>> contextMap;
1.91 +
1.92 + /** current translation context (visitor argument) */
1.93 + private TranslationContext<?> context;
1.94 +
1.95 + /** list of translated methods
1.96 + **/
1.97 + private ListBuffer<JCTree> translatedMethodList;
1.98 +
1.99 + // <editor-fold defaultstate="collapsed" desc="Instantiating">
1.100 + private static final Context.Key<LambdaToMethod> unlambdaKey =
1.101 + new Context.Key<LambdaToMethod>();
1.102 +
1.103 + public static LambdaToMethod instance(Context context) {
1.104 + LambdaToMethod instance = context.get(unlambdaKey);
1.105 + if (instance == null) {
1.106 + instance = new LambdaToMethod(context);
1.107 + }
1.108 + return instance;
1.109 + }
1.110 +
1.111 + private LambdaToMethod(Context context) {
1.112 + names = Names.instance(context);
1.113 + syms = Symtab.instance(context);
1.114 + rs = Resolve.instance(context);
1.115 + make = TreeMaker.instance(context);
1.116 + types = Types.instance(context);
1.117 + transTypes = TransTypes.instance(context);
1.118 + this.analyzer = makeAnalyzer();
1.119 + }
1.120 +
1.121 + private LambdaAnalyzer makeAnalyzer() {
1.122 + return new LambdaAnalyzer();
1.123 + }
1.124 + // </editor-fold>
1.125 +
1.126 + // <editor-fold defaultstate="collapsed" desc="translate methods">
1.127 + @Override
1.128 + public <T extends JCTree> T translate(T tree) {
1.129 + TranslationContext<?> newContext = contextMap.get(tree);
1.130 + return translate(tree, newContext != null ? newContext : context);
1.131 + }
1.132 +
1.133 + public <T extends JCTree> T translate(T tree, TranslationContext<?> newContext) {
1.134 + TranslationContext<?> prevContext = context;
1.135 + try {
1.136 + context = newContext;
1.137 + return super.translate(tree);
1.138 + }
1.139 + finally {
1.140 + context = prevContext;
1.141 + }
1.142 + }
1.143 +
1.144 + public <T extends JCTree> List<T> translate(List<T> trees, TranslationContext<?> newContext) {
1.145 + ListBuffer<T> buf = ListBuffer.lb();
1.146 + for (T tree : trees) {
1.147 + buf.append(translate(tree, newContext));
1.148 + }
1.149 + return buf.toList();
1.150 + }
1.151 +
1.152 + public JCTree translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) {
1.153 + this.make = make;
1.154 + this.attrEnv = env;
1.155 + this.context = null;
1.156 + this.contextMap = new HashMap<JCTree, TranslationContext<?>>();
1.157 + return translate(cdef);
1.158 + }
1.159 + // </editor-fold>
1.160 +
1.161 + // <editor-fold defaultstate="collapsed" desc="visitor methods">
1.162 + /**
1.163 + * Visit a class.
1.164 + * Maintain the translatedMethodList across nested classes.
1.165 + * Append the translatedMethodList to the class after it is translated.
1.166 + * @param tree
1.167 + */
1.168 + @Override
1.169 + public void visitClassDef(JCClassDecl tree) {
1.170 + if (tree.sym.owner.kind == PCK) {
1.171 + //analyze class
1.172 + analyzer.analyzeClass(tree);
1.173 + }
1.174 + ListBuffer<JCTree> prevTranslated = translatedMethodList;
1.175 + try {
1.176 + translatedMethodList = ListBuffer.lb();
1.177 + super.visitClassDef(tree);
1.178 + //add all translated instance methods here
1.179 + tree.defs = tree.defs.appendList(translatedMethodList.toList());
1.180 + for (JCTree lambda : translatedMethodList) {
1.181 + tree.sym.members().enter(((JCMethodDecl)lambda).sym);
1.182 + }
1.183 + result = tree;
1.184 + } finally {
1.185 + translatedMethodList = prevTranslated;
1.186 + }
1.187 + }
1.188 +
1.189 + /**
1.190 + * Translate a lambda into a method to be inserted into the class.
1.191 + * Then replace the lambda site with an invokedynamic call of to lambda
1.192 + * meta-factory, which will use the lambda method.
1.193 + * @param tree
1.194 + */
1.195 + @Override
1.196 + public void visitLambda(JCLambda tree) {
1.197 + LambdaTranslationContext localContext = (LambdaTranslationContext)context;
1.198 + MethodSymbol sym = (MethodSymbol)localContext.translatedSym;
1.199 + MethodType lambdaType = (MethodType) sym.type;
1.200 +
1.201 + //create the method declaration hoisting the lambda body
1.202 + JCMethodDecl lambdaDecl = make.MethodDef(make.Modifiers(sym.flags_field),
1.203 + sym.name,
1.204 + make.QualIdent(lambdaType.getReturnType().tsym),
1.205 + List.<JCTypeParameter>nil(),
1.206 + localContext.syntheticParams,
1.207 + lambdaType.getThrownTypes() == null ?
1.208 + List.<JCExpression>nil() :
1.209 + make.Types(lambdaType.getThrownTypes()),
1.210 + null,
1.211 + null);
1.212 + lambdaDecl.sym = sym;
1.213 + lambdaDecl.type = lambdaType;
1.214 +
1.215 + //translate lambda body
1.216 + //As the lambda body is translated, all references to lambda locals,
1.217 + //captured variables, enclosing members are adjusted accordingly
1.218 + //to refer to the static method parameters (rather than i.e. acessing to
1.219 + //captured members directly).
1.220 + lambdaDecl.body = translate(makeLambdaBody(tree, lambdaDecl));
1.221 +
1.222 + //Add the method to the list of methods to be added to this class.
1.223 + translatedMethodList = translatedMethodList.prepend(lambdaDecl);
1.224 +
1.225 + //now that we have generated a method for the lambda expression,
1.226 + //we can translate the lambda into a method reference pointing to the newly
1.227 + //created method.
1.228 + //
1.229 + //Note that we need to adjust the method handle so that it will match the
1.230 + //signature of the SAM descriptor - this means that the method reference
1.231 + //should be added the following synthetic arguments:
1.232 + //
1.233 + // * the "this" argument if it is an instance method
1.234 + // * enclosing locals captured by the lambda expression
1.235 +
1.236 + ListBuffer<JCExpression> syntheticInits = ListBuffer.lb();
1.237 +
1.238 + if (!sym.isStatic()) {
1.239 + syntheticInits.append(makeThis(
1.240 + sym.owner.asType(),
1.241 + localContext.owner.enclClass()));
1.242 + }
1.243 +
1.244 + //add captured locals
1.245 + for (Symbol fv : localContext.getSymbolMap(CAPTURED_VAR).keySet()) {
1.246 + if (fv != localContext.self) {
1.247 + JCTree captured_local = make.Ident(fv).setType(fv.type);
1.248 + syntheticInits.append((JCExpression) captured_local);
1.249 + }
1.250 + }
1.251 +
1.252 + //then, determine the arguments to the indy call
1.253 + List<JCExpression> indy_args = translate(syntheticInits.toList(), localContext.prev);
1.254 +
1.255 + //build a sam instance using an indy call to the meta-factory
1.256 + int refKind = referenceKind(sym);
1.257 +
1.258 + //convert to an invokedynamic call
1.259 + result = makeMetaFactoryIndyCall(tree, tree.targetType, refKind, sym, indy_args);
1.260 + }
1.261 +
1.262 + private JCIdent makeThis(Type type, Symbol owner) {
1.263 + VarSymbol _this = new VarSymbol(PARAMETER | FINAL | SYNTHETIC,
1.264 + names._this,
1.265 + type,
1.266 + owner);
1.267 + return make.Ident(_this);
1.268 + }
1.269 +
1.270 + /**
1.271 + * Translate a method reference into an invokedynamic call to the
1.272 + * meta-factory.
1.273 + * @param tree
1.274 + */
1.275 + @Override
1.276 + public void visitReference(JCMemberReference tree) {
1.277 + ReferenceTranslationContext localContext = (ReferenceTranslationContext)context;
1.278 +
1.279 + //first determine the method symbol to be used to generate the sam instance
1.280 + //this is either the method reference symbol, or the bridged reference symbol
1.281 + Symbol refSym = localContext.needsBridge() ?
1.282 + localContext.bridgeSym :
1.283 + tree.sym;
1.284 +
1.285 + //build the bridge method, if needed
1.286 + if (localContext.needsBridge()) {
1.287 + bridgeMemberReference(tree, localContext);
1.288 + }
1.289 +
1.290 + //the qualifying expression is treated as a special captured arg
1.291 + JCExpression init;
1.292 + switch(tree.kind) {
1.293 +
1.294 + case IMPLICIT_INNER: /** Inner # new */
1.295 + case SUPER: /** super # instMethod */
1.296 + init = makeThis(
1.297 + localContext.owner.owner.asType(),
1.298 + localContext.owner);
1.299 + break;
1.300 +
1.301 + case BOUND: /** Expr # instMethod */
1.302 + init = tree.getQualifierExpression();
1.303 + break;
1.304 +
1.305 + case STATIC_EVAL: /** Expr # staticMethod */
1.306 + case UNBOUND: /** Type # instMethod */
1.307 + case STATIC: /** Type # staticMethod */
1.308 + case TOPLEVEL: /** Top level # new */
1.309 + init = null;
1.310 + break;
1.311 +
1.312 + default:
1.313 + throw new InternalError("Should not have an invalid kind");
1.314 + }
1.315 +
1.316 + List<JCExpression> indy_args = init==null? List.<JCExpression>nil() : translate(List.of(init), localContext.prev);
1.317 +
1.318 +
1.319 + //build a sam instance using an indy call to the meta-factory
1.320 + result = makeMetaFactoryIndyCall(tree, tree.targetType, localContext.referenceKind(), refSym, indy_args);
1.321 +
1.322 + //if we had a static reference with non-static qualifier, add a let
1.323 + //expression to force the evaluation of the qualifier expr
1.324 + if (tree.hasKind(ReferenceKind.STATIC_EVAL)) {
1.325 + VarSymbol rec = new VarSymbol(0, names.fromString("rec$"), tree.getQualifierExpression().type, localContext.owner);
1.326 + JCVariableDecl recDef = make.VarDef(rec, tree.getQualifierExpression());
1.327 + result = make.LetExpr(recDef, result).setType(tree.type);
1.328 + }
1.329 + }
1.330 +
1.331 + /**
1.332 + * Translate identifiers within a lambda to the mapped identifier
1.333 + * @param tree
1.334 + */
1.335 + @Override
1.336 + public void visitIdent(JCIdent tree) {
1.337 + if (context == null || !analyzer.lambdaIdentSymbolFilter(tree.sym)) {
1.338 + super.visitIdent(tree);
1.339 + } else {
1.340 + LambdaTranslationContext lambdaContext = (LambdaTranslationContext) context;
1.341 + if (lambdaContext.getSymbolMap(PARAM).containsKey(tree.sym)) {
1.342 + Symbol translatedSym = lambdaContext.getSymbolMap(PARAM).get(tree.sym);
1.343 + result = make.Ident(translatedSym).setType(tree.type);
1.344 + } else if (lambdaContext.getSymbolMap(LOCAL_VAR).containsKey(tree.sym)) {
1.345 + Symbol translatedSym = lambdaContext.getSymbolMap(LOCAL_VAR).get(tree.sym);
1.346 + result = make.Ident(translatedSym).setType(tree.type);
1.347 + } else if (lambdaContext.getSymbolMap(CAPTURED_VAR).containsKey(tree.sym)) {
1.348 + Symbol translatedSym = lambdaContext.getSymbolMap(CAPTURED_VAR).get(tree.sym);
1.349 + result = make.Ident(translatedSym).setType(tree.type);
1.350 + } else {
1.351 + if (tree.sym.owner.kind == Kinds.TYP) {
1.352 + for (Map.Entry<Symbol, Symbol> encl_entry : lambdaContext.getSymbolMap(CAPTURED_THIS).entrySet()) {
1.353 + if (tree.sym.isMemberOf((ClassSymbol) encl_entry.getKey(), types)) {
1.354 + JCExpression enclRef = make.Ident(encl_entry.getValue());
1.355 + result = tree.sym.name == names._this
1.356 + ? enclRef.setType(tree.type)
1.357 + : make.Select(enclRef, tree.sym).setType(tree.type);
1.358 + result = tree;
1.359 + return;
1.360 + }
1.361 + }
1.362 + }
1.363 + //access to untranslated symbols (i.e. compile-time constants,
1.364 + //members defined inside the lambda body, etc.) )
1.365 + super.visitIdent(tree);
1.366 + }
1.367 + }
1.368 + }
1.369 +
1.370 + @Override
1.371 + public void visitVarDef(JCVariableDecl tree) {
1.372 + LambdaTranslationContext lambdaContext = (LambdaTranslationContext)context;
1.373 + if (context != null && lambdaContext.getSymbolMap(LOCAL_VAR).containsKey(tree.sym)) {
1.374 + JCExpression init = translate(tree.init);
1.375 + result = make.VarDef((VarSymbol)lambdaContext.getSymbolMap(LOCAL_VAR).get(tree.sym), init);
1.376 + } else {
1.377 + super.visitVarDef(tree);
1.378 + }
1.379 + }
1.380 +
1.381 + // </editor-fold>
1.382 +
1.383 + // <editor-fold defaultstate="collapsed" desc="Translation helper methods">
1.384 +
1.385 + private JCBlock makeLambdaBody(JCLambda tree, JCMethodDecl lambdaMethodDecl) {
1.386 + return tree.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
1.387 + makeLambdaExpressionBody((JCExpression)tree.body, lambdaMethodDecl) :
1.388 + makeLambdaStatementBody((JCBlock)tree.body, lambdaMethodDecl, tree.canCompleteNormally);
1.389 + }
1.390 +
1.391 + private JCBlock makeLambdaExpressionBody(JCExpression expr, JCMethodDecl lambdaMethodDecl) {
1.392 + Type restype = lambdaMethodDecl.type.getReturnType();
1.393 + boolean isLambda_void = expr.type.hasTag(VOID);
1.394 + boolean isTarget_void = restype.hasTag(VOID);
1.395 + boolean isTarget_Void = types.isSameType(restype, types.boxedClass(syms.voidType).type);
1.396 + if (isTarget_void) {
1.397 + //target is void:
1.398 + // BODY;
1.399 + JCStatement stat = make.Exec(expr);
1.400 + return make.Block(0, List.<JCStatement>of(stat));
1.401 + } else if (isLambda_void && isTarget_Void) {
1.402 + //void to Void conversion:
1.403 + // BODY; return null;
1.404 + ListBuffer<JCStatement> stats = ListBuffer.lb();
1.405 + stats.append(make.Exec(expr));
1.406 + stats.append(make.Return(make.Literal(BOT, null).setType(syms.botType)));
1.407 + return make.Block(0, stats.toList());
1.408 + } else {
1.409 + //non-void to non-void conversion:
1.410 + // return (TYPE)BODY;
1.411 + JCExpression retExpr = transTypes.coerce(attrEnv, expr, restype);
1.412 + return make.Block(0, List.<JCStatement>of(make.Return(retExpr)));
1.413 + }
1.414 + }
1.415 +
1.416 + private JCBlock makeLambdaStatementBody(JCBlock block, final JCMethodDecl lambdaMethodDecl, boolean completeNormally) {
1.417 + final Type restype = lambdaMethodDecl.type.getReturnType();
1.418 + final boolean isTarget_void = restype.hasTag(VOID);
1.419 + boolean isTarget_Void = types.isSameType(restype, types.boxedClass(syms.voidType).type);
1.420 +
1.421 + class LambdaBodyTranslator extends TreeTranslator {
1.422 +
1.423 + @Override
1.424 + public void visitClassDef(JCClassDecl tree) {
1.425 + //do NOT recurse on any inner classes
1.426 + result = tree;
1.427 + }
1.428 +
1.429 + @Override
1.430 + public void visitLambda(JCLambda tree) {
1.431 + //do NOT recurse on any nested lambdas
1.432 + result = tree;
1.433 + }
1.434 +
1.435 + @Override
1.436 + public void visitReturn(JCReturn tree) {
1.437 + boolean isLambda_void = tree.expr == null;
1.438 + if (isTarget_void && !isLambda_void) {
1.439 + //Void to void conversion:
1.440 + // { TYPE $loc = RET-EXPR; return; }
1.441 + VarSymbol loc = makeSyntheticVar(0, names.fromString("$loc"), tree.expr.type, lambdaMethodDecl.sym);
1.442 + JCVariableDecl varDef = make.VarDef(loc, tree.expr);
1.443 + result = make.Block(0, List.<JCStatement>of(varDef, make.Return(null)));
1.444 + } else if (!isTarget_void || !isLambda_void) {
1.445 + //non-void to non-void conversion:
1.446 + // return (TYPE)RET-EXPR;
1.447 + tree.expr = transTypes.coerce(attrEnv, tree.expr, restype);
1.448 + result = tree;
1.449 + } else {
1.450 + result = tree;
1.451 + }
1.452 +
1.453 + }
1.454 + }
1.455 +
1.456 + JCBlock trans_block = new LambdaBodyTranslator().translate(block);
1.457 + if (completeNormally && isTarget_Void) {
1.458 + //there's no return statement and the lambda (possibly inferred)
1.459 + //return type is java.lang.Void; emit a synthetic return statement
1.460 + trans_block.stats = trans_block.stats.append(make.Return(make.Literal(BOT, null).setType(syms.botType)));
1.461 + }
1.462 + return trans_block;
1.463 + }
1.464 +
1.465 + /**
1.466 + * Create new synthetic method with given flags, name, type, owner
1.467 + */
1.468 + private MethodSymbol makeSyntheticMethod(long flags, Name name, Type type, Symbol owner) {
1.469 + return new MethodSymbol(flags | SYNTHETIC, name, type, owner);
1.470 + }
1.471 +
1.472 + /**
1.473 + * Create new synthetic variable with given flags, name, type, owner
1.474 + */
1.475 + private VarSymbol makeSyntheticVar(long flags, String name, Type type, Symbol owner) {
1.476 + return makeSyntheticVar(flags, names.fromString(name), type, owner);
1.477 + }
1.478 +
1.479 + /**
1.480 + * Create new synthetic variable with given flags, name, type, owner
1.481 + */
1.482 + private VarSymbol makeSyntheticVar(long flags, Name name, Type type, Symbol owner) {
1.483 + return new VarSymbol(flags | SYNTHETIC, name, type, owner);
1.484 + }
1.485 +
1.486 + /**
1.487 + * Set varargsElement field on a given tree (must be either a new class tree
1.488 + * or a method call tree)
1.489 + */
1.490 + private void setVarargsIfNeeded(JCTree tree, Type varargsElement) {
1.491 + if (varargsElement != null) {
1.492 + switch (tree.getTag()) {
1.493 + case APPLY: ((JCMethodInvocation)tree).varargsElement = varargsElement; break;
1.494 + case NEWCLASS: ((JCNewClass)tree).varargsElement = varargsElement; break;
1.495 + default: throw new AssertionError();
1.496 + }
1.497 + }
1.498 + }
1.499 +
1.500 + /**
1.501 + * Convert method/constructor arguments by inserting appropriate cast
1.502 + * as required by type-erasure - this is needed when bridging a lambda/method
1.503 + * reference, as the bridged signature might require downcast to be compatible
1.504 + * with the generated signature.
1.505 + */
1.506 + private List<JCExpression> convertArgs(Symbol meth, List<JCExpression> args, Type varargsElement) {
1.507 + Assert.check(meth.kind == Kinds.MTH);
1.508 + List<Type> formals = types.erasure(meth.type).getParameterTypes();
1.509 + if (varargsElement != null) {
1.510 + Assert.check((meth.flags() & VARARGS) != 0);
1.511 + }
1.512 + return transTypes.translateArgs(args, formals, varargsElement, attrEnv);
1.513 + }
1.514 +
1.515 + // </editor-fold>
1.516 +
1.517 + private MethodSymbol makeSamDescriptor(Type targetType) {
1.518 + return (MethodSymbol)types.findDescriptorSymbol(targetType.tsym);
1.519 + }
1.520 +
1.521 + private Type makeFunctionalDescriptorType(Type targetType, MethodSymbol samDescriptor, boolean erased) {
1.522 + Type descType = types.memberType(targetType, samDescriptor);
1.523 + return erased ? types.erasure(descType) : descType;
1.524 + }
1.525 +
1.526 + private Type makeFunctionalDescriptorType(Type targetType, boolean erased) {
1.527 + return makeFunctionalDescriptorType(targetType, makeSamDescriptor(targetType), erased);
1.528 + }
1.529 +
1.530 + /**
1.531 + * Generate an adapter method "bridge" for a method reference which cannot
1.532 + * be used directly.
1.533 + */
1.534 + private class MemberReferenceBridger {
1.535 +
1.536 + private final JCMemberReference tree;
1.537 + private final ReferenceTranslationContext localContext;
1.538 + private final ListBuffer<JCExpression> args = ListBuffer.lb();
1.539 + private final ListBuffer<JCVariableDecl> params = ListBuffer.lb();
1.540 +
1.541 + MemberReferenceBridger(JCMemberReference tree, ReferenceTranslationContext localContext) {
1.542 + this.tree = tree;
1.543 + this.localContext = localContext;
1.544 + }
1.545 +
1.546 + /**
1.547 + * Generate the bridge
1.548 + */
1.549 + JCMethodDecl bridge() {
1.550 + int prevPos = make.pos;
1.551 + try {
1.552 + make.at(tree);
1.553 + Type samDesc = localContext.bridgedRefSig();
1.554 + List<Type> samPTypes = samDesc.getParameterTypes();
1.555 +
1.556 + //an extra argument is prepended to the signature of the bridge in case
1.557 + //the member reference is an instance method reference (in which case
1.558 + //the receiver expression is passed to the bridge itself).
1.559 + Type recType = null;
1.560 + switch (tree.kind) {
1.561 + case IMPLICIT_INNER:
1.562 + recType = tree.sym.owner.type.getEnclosingType();
1.563 + break;
1.564 + case BOUND:
1.565 + recType = tree.getQualifierExpression().type;
1.566 + break;
1.567 + case UNBOUND:
1.568 + recType = samPTypes.head;
1.569 + samPTypes = samPTypes.tail;
1.570 + break;
1.571 + }
1.572 +
1.573 + //generate the parameter list for the bridged member reference - the
1.574 + //bridge signature will match the signature of the target sam descriptor
1.575 +
1.576 + VarSymbol rcvr = (recType == null)
1.577 + ? null
1.578 + : addParameter("rec$", recType, false);
1.579 +
1.580 + List<Type> refPTypes = tree.sym.type.getParameterTypes();
1.581 + int refSize = refPTypes.size();
1.582 + int samSize = samPTypes.size();
1.583 + int last = localContext.needsVarArgsConversion() ? refSize - 1 : refSize; // Last parameter to copy from referenced method
1.584 +
1.585 + List<Type> l = refPTypes;
1.586 + // Use parameter types of the referenced method, excluding final var args
1.587 + for (int i = 0; l.nonEmpty() && i < last; ++i) {
1.588 + addParameter("x$" + i, l.head, true);
1.589 + l = l.tail;
1.590 + }
1.591 + // Flatten out the var args
1.592 + for (int i = last; i < samSize; ++i) {
1.593 + addParameter("xva$" + i, tree.varargsElement, true);
1.594 + }
1.595 +
1.596 + //generate the bridge method declaration
1.597 + JCMethodDecl bridgeDecl = make.MethodDef(make.Modifiers(localContext.bridgeSym.flags()),
1.598 + localContext.bridgeSym.name,
1.599 + make.QualIdent(samDesc.getReturnType().tsym),
1.600 + List.<JCTypeParameter>nil(),
1.601 + params.toList(),
1.602 + tree.sym.type.getThrownTypes() == null
1.603 + ? List.<JCExpression>nil()
1.604 + : make.Types(tree.sym.type.getThrownTypes()),
1.605 + null,
1.606 + null);
1.607 + bridgeDecl.sym = (MethodSymbol) localContext.bridgeSym;
1.608 + bridgeDecl.type = localContext.bridgeSym.type = types.createMethodTypeWithParameters(samDesc, TreeInfo.types(params.toList()));
1.609 +
1.610 + //bridge method body generation - this can be either a method call or a
1.611 + //new instance creation expression, depending on the member reference kind
1.612 + JCExpression bridgeExpr = (tree.getMode() == ReferenceMode.INVOKE)
1.613 + ? bridgeExpressionInvoke(rcvr)
1.614 + : bridgeExpressionNew();
1.615 +
1.616 + //the body is either a return expression containing a method call,
1.617 + //or the method call itself, depending on whether the return type of
1.618 + //the bridge is non-void/void.
1.619 + bridgeDecl.body = makeLambdaExpressionBody(bridgeExpr, bridgeDecl);
1.620 +
1.621 + return bridgeDecl;
1.622 + } finally {
1.623 + make.at(prevPos);
1.624 + }
1.625 + }
1.626 +
1.627 + /**
1.628 + * determine the receiver of the bridged method call - the receiver can
1.629 + * be either the synthetic receiver parameter or a type qualifier; the
1.630 + * original qualifier expression is never used here, as it might refer
1.631 + * to symbols not available in the static context of the bridge
1.632 + */
1.633 + private JCExpression bridgeExpressionInvoke(VarSymbol rcvr) {
1.634 + JCExpression qualifier =
1.635 + tree.sym.isStatic() ?
1.636 + make.Type(tree.sym.owner.type) :
1.637 + (rcvr != null) ?
1.638 + make.Ident(rcvr) :
1.639 + tree.getQualifierExpression();
1.640 +
1.641 + //create the qualifier expression
1.642 + JCFieldAccess select = make.Select(qualifier, tree.sym.name);
1.643 + select.sym = tree.sym;
1.644 + select.type = tree.sym.erasure(types);
1.645 +
1.646 + //create the method call expression
1.647 + JCExpression apply = make.Apply(List.<JCExpression>nil(), select,
1.648 + convertArgs(tree.sym, args.toList(), tree.varargsElement)).setType(tree.sym.erasure(types).getReturnType());
1.649 +
1.650 + apply = transTypes.coerce(apply, localContext.generatedRefSig().getReturnType());
1.651 + setVarargsIfNeeded(apply, tree.varargsElement);
1.652 + return apply;
1.653 + }
1.654 +
1.655 + /**
1.656 + * the enclosing expression is either 'null' (no enclosing type) or set
1.657 + * to the first bridge synthetic parameter
1.658 + */
1.659 + private JCExpression bridgeExpressionNew() {
1.660 + JCExpression encl = null;
1.661 + switch (tree.kind) {
1.662 + case UNBOUND:
1.663 + case IMPLICIT_INNER:
1.664 + encl = make.Ident(params.first());
1.665 + }
1.666 +
1.667 + //create the instance creation expression
1.668 + JCNewClass newClass = make.NewClass(encl,
1.669 + List.<JCExpression>nil(),
1.670 + make.Type(tree.getQualifierExpression().type),
1.671 + convertArgs(tree.sym, args.toList(), tree.varargsElement),
1.672 + null);
1.673 + newClass.constructor = tree.sym;
1.674 + newClass.constructorType = tree.sym.erasure(types);
1.675 + newClass.type = tree.getQualifierExpression().type;
1.676 + setVarargsIfNeeded(newClass, tree.varargsElement);
1.677 + return newClass;
1.678 + }
1.679 +
1.680 + private VarSymbol addParameter(String name, Type p, boolean genArg) {
1.681 + VarSymbol vsym = new VarSymbol(0, names.fromString(name), p, localContext.bridgeSym);
1.682 + params.append(make.VarDef(vsym, null));
1.683 + if (genArg) {
1.684 + args.append(make.Ident(vsym));
1.685 + }
1.686 + return vsym;
1.687 + }
1.688 + }
1.689 +
1.690 + /**
1.691 + * Bridges a member reference - this is needed when:
1.692 + * * Var args in the referenced method need to be flattened away
1.693 + * * super is used
1.694 + */
1.695 + private void bridgeMemberReference(JCMemberReference tree, ReferenceTranslationContext localContext) {
1.696 + JCMethodDecl bridgeDecl = (new MemberReferenceBridger(tree, localContext).bridge());
1.697 + translatedMethodList = translatedMethodList.prepend(bridgeDecl);
1.698 + }
1.699 +
1.700 + /**
1.701 + * Generate an indy method call to the meta factory
1.702 + */
1.703 + private JCExpression makeMetaFactoryIndyCall(JCExpression tree, Type targetType, int refKind, Symbol refSym, List<JCExpression> indy_args) {
1.704 + //determine the static bsm args
1.705 + Type mtype = makeFunctionalDescriptorType(targetType, true);
1.706 + List<Object> staticArgs = List.<Object>of(
1.707 + new Pool.MethodHandle(ClassFile.REF_invokeInterface, types.findDescriptorSymbol(targetType.tsym)),
1.708 + new Pool.MethodHandle(refKind, refSym),
1.709 + new MethodType(mtype.getParameterTypes(),
1.710 + mtype.getReturnType(),
1.711 + mtype.getThrownTypes(),
1.712 + syms.methodClass));
1.713 +
1.714 + //computed indy arg types
1.715 + ListBuffer<Type> indy_args_types = ListBuffer.lb();
1.716 + for (JCExpression arg : indy_args) {
1.717 + indy_args_types.append(arg.type);
1.718 + }
1.719 +
1.720 + //finally, compute the type of the indy call
1.721 + MethodType indyType = new MethodType(indy_args_types.toList(),
1.722 + tree.type,
1.723 + List.<Type>nil(),
1.724 + syms.methodClass);
1.725 +
1.726 + return makeIndyCall(tree, syms.lambdaMetafactory, names.metaFactory, staticArgs, indyType, indy_args);
1.727 + }
1.728 +
1.729 + /**
1.730 + * Generate an indy method call with given name, type and static bootstrap
1.731 + * arguments types
1.732 + */
1.733 + private JCExpression makeIndyCall(DiagnosticPosition pos, Type site, Name bsmName, List<Object> staticArgs, MethodType indyType, List<JCExpression> indyArgs) {
1.734 + int prevPos = make.pos;
1.735 + try {
1.736 + make.at(pos);
1.737 + List<Type> bsm_staticArgs = List.of(syms.methodHandleLookupType,
1.738 + syms.stringType,
1.739 + syms.methodTypeType).appendList(bsmStaticArgToTypes(staticArgs));
1.740 +
1.741 + Symbol bsm = rs.resolveInternalMethod(pos, attrEnv, site,
1.742 + bsmName, bsm_staticArgs, List.<Type>nil());
1.743 +
1.744 + DynamicMethodSymbol dynSym =
1.745 + new DynamicMethodSymbol(names.lambda,
1.746 + syms.noSymbol,
1.747 + bsm.isStatic() ? ClassFile.REF_invokeStatic : ClassFile.REF_invokeVirtual,
1.748 + (MethodSymbol)bsm,
1.749 + indyType,
1.750 + staticArgs.toArray());
1.751 +
1.752 + JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), bsmName);
1.753 + qualifier.sym = dynSym;
1.754 + qualifier.type = indyType.getReturnType();
1.755 +
1.756 + JCMethodInvocation proxyCall = make.Apply(List.<JCExpression>nil(), qualifier, indyArgs);
1.757 + proxyCall.type = indyType.getReturnType();
1.758 + return proxyCall;
1.759 + } finally {
1.760 + make.at(prevPos);
1.761 + }
1.762 + }
1.763 + //where
1.764 + private List<Type> bsmStaticArgToTypes(List<Object> args) {
1.765 + ListBuffer<Type> argtypes = ListBuffer.lb();
1.766 + for (Object arg : args) {
1.767 + argtypes.append(bsmStaticArgToType(arg));
1.768 + }
1.769 + return argtypes.toList();
1.770 + }
1.771 +
1.772 + private Type bsmStaticArgToType(Object arg) {
1.773 + Assert.checkNonNull(arg);
1.774 + if (arg instanceof ClassSymbol) {
1.775 + return syms.classType;
1.776 + } else if (arg instanceof Integer) {
1.777 + return syms.intType;
1.778 + } else if (arg instanceof Long) {
1.779 + return syms.longType;
1.780 + } else if (arg instanceof Float) {
1.781 + return syms.floatType;
1.782 + } else if (arg instanceof Double) {
1.783 + return syms.doubleType;
1.784 + } else if (arg instanceof String) {
1.785 + return syms.stringType;
1.786 + } else if (arg instanceof Pool.MethodHandle) {
1.787 + return syms.methodHandleType;
1.788 + } else if (arg instanceof MethodType) {
1.789 + return syms.methodTypeType;
1.790 + } else {
1.791 + Assert.error("bad static arg " + arg.getClass());
1.792 + return null;
1.793 + }
1.794 + }
1.795 +
1.796 + /**
1.797 + * Get the opcode associated with this method reference
1.798 + */
1.799 + private int referenceKind(Symbol refSym) {
1.800 + if (refSym.isConstructor()) {
1.801 + return ClassFile.REF_newInvokeSpecial;
1.802 + } else {
1.803 + if (refSym.isStatic()) {
1.804 + return ClassFile.REF_invokeStatic;
1.805 + } else if (refSym.enclClass().isInterface()) {
1.806 + return ClassFile.REF_invokeInterface;
1.807 + } else {
1.808 + return ClassFile.REF_invokeVirtual;
1.809 + }
1.810 + }
1.811 + }
1.812 + // </editor-fold>
1.813 +
1.814 + // <editor-fold defaultstate="collapsed" desc="Lambda/reference analyzer">\
1.815 + /**
1.816 + * This visitor collects information about translation of a lambda expression.
1.817 + * More specifically, it keeps track of the enclosing contexts and captured locals
1.818 + * accessed by the lambda being translated (as well as other useful info).
1.819 + */
1.820 + class LambdaAnalyzer extends TreeScanner {
1.821 +
1.822 + /** the frame stack - used to reconstruct translation info about enclosing scopes */
1.823 + private List<Frame> frameStack;
1.824 +
1.825 + /**
1.826 + * keep the count of lambda expression (used to generate unambiguous
1.827 + * names)
1.828 + */
1.829 + private int lambdaCount = 0;
1.830 +
1.831 + private void analyzeClass(JCClassDecl tree) {
1.832 + frameStack = List.nil();
1.833 + scan(tree);
1.834 + }
1.835 +
1.836 + @Override
1.837 + public void visitBlock(JCBlock tree) {
1.838 + List<Frame> prevStack = frameStack;
1.839 + try {
1.840 + if (frameStack.nonEmpty() && frameStack.head.tree.hasTag(CLASSDEF)) {
1.841 + frameStack = frameStack.prepend(new Frame(tree));
1.842 + }
1.843 + super.visitBlock(tree);
1.844 + }
1.845 + finally {
1.846 + frameStack = prevStack;
1.847 + }
1.848 + }
1.849 +
1.850 + @Override
1.851 + public void visitClassDef(JCClassDecl tree) {
1.852 + List<Frame> prevStack = frameStack;
1.853 + try {
1.854 + if (frameStack.nonEmpty() && enclosingLambda() != null) {
1.855 + tree.sym.owner = owner();
1.856 + LambdaTranslationContext lambdaContext = (LambdaTranslationContext)contextMap.get(enclosingLambda());
1.857 + Type encl = lambdaContext.enclosingType();
1.858 + if (encl.hasTag(NONE)) {
1.859 + //if the translated lambda body occurs in a static context,
1.860 + //any class declaration within it must be made static
1.861 + tree.sym.flags_field |= STATIC;
1.862 + ((ClassType)tree.sym.type).setEnclosingType(Type.noType);
1.863 + } else {
1.864 + //if the translated lambda body is in an instance context
1.865 + //the enclosing type of any class declaration within it
1.866 + //must be updated to point to the new enclosing type (if any)
1.867 + ((ClassType)tree.sym.type).setEnclosingType(encl);
1.868 + }
1.869 + }
1.870 + frameStack = frameStack.prepend(new Frame(tree));
1.871 + super.visitClassDef(tree);
1.872 + }
1.873 + finally {
1.874 + frameStack = prevStack;
1.875 + }
1.876 + if (frameStack.nonEmpty() && enclosingLambda() != null) {
1.877 + // Any class defined within a lambda is an implicit 'this' reference
1.878 + // because its constructor will reference the enclosing class
1.879 + ((LambdaTranslationContext) context()).addSymbol(tree.sym.type.getEnclosingType().tsym, CAPTURED_THIS);
1.880 + }
1.881 + }
1.882 +
1.883 + @Override
1.884 + public void visitIdent(JCIdent tree) {
1.885 + if (context() == null || !lambdaIdentSymbolFilter(tree.sym)) {
1.886 + super.visitIdent(tree);
1.887 + } else {
1.888 + if (tree.sym.kind == VAR &&
1.889 + tree.sym.owner.kind == MTH &&
1.890 + tree.type.constValue() == null) {
1.891 + TranslationContext<?> localContext = context();
1.892 + while (localContext != null) {
1.893 + if (localContext.tree.getTag() == LAMBDA) {
1.894 + JCTree block = capturedDecl(localContext.depth, tree.sym);
1.895 + if (block == null) break;
1.896 + ((LambdaTranslationContext)localContext).addSymbol(tree.sym, CAPTURED_VAR);
1.897 + }
1.898 + localContext = localContext.prev;
1.899 + }
1.900 + } else if (tree.sym.owner.kind == TYP) {
1.901 + TranslationContext<?> localContext = context();
1.902 + while (localContext != null) {
1.903 + if (localContext.tree.hasTag(LAMBDA)) {
1.904 + JCTree block = capturedDecl(localContext.depth, tree.sym);
1.905 + if (block == null) break;
1.906 + switch (block.getTag()) {
1.907 + case CLASSDEF:
1.908 + JCClassDecl cdecl = (JCClassDecl)block;
1.909 + ((LambdaTranslationContext)localContext).addSymbol(cdecl.sym, CAPTURED_THIS);
1.910 + break;
1.911 + default:
1.912 + Assert.error("bad block kind");
1.913 + }
1.914 + }
1.915 + localContext = localContext.prev;
1.916 + }
1.917 + }
1.918 + }
1.919 + }
1.920 +
1.921 + @Override
1.922 + public void visitLambda(JCLambda tree) {
1.923 + List<Frame> prevStack = frameStack;
1.924 + try {
1.925 + LambdaTranslationContext context = (LambdaTranslationContext)makeLambdaContext(tree);
1.926 + frameStack = frameStack.prepend(new Frame(tree));
1.927 + for (JCVariableDecl param : tree.params) {
1.928 + context.addSymbol(param.sym, PARAM);
1.929 + frameStack.head.addLocal(param.sym);
1.930 + }
1.931 + contextMap.put(tree, context);
1.932 + scan(tree.body);
1.933 + context.complete();
1.934 + }
1.935 + finally {
1.936 + frameStack = prevStack;
1.937 + }
1.938 + }
1.939 +
1.940 + @Override
1.941 + public void visitMethodDef(JCMethodDecl tree) {
1.942 + List<Frame> prevStack = frameStack;
1.943 + try {
1.944 + frameStack = frameStack.prepend(new Frame(tree));
1.945 + super.visitMethodDef(tree);
1.946 + }
1.947 + finally {
1.948 + frameStack = prevStack;
1.949 + }
1.950 + }
1.951 +
1.952 + @Override
1.953 + public void visitNewClass(JCNewClass tree) {
1.954 + if (lambdaNewClassFilter(context(), tree)) {
1.955 + ((LambdaTranslationContext) context()).addSymbol(tree.type.getEnclosingType().tsym, CAPTURED_THIS);
1.956 + }
1.957 + super.visitNewClass(tree);
1.958 + }
1.959 +
1.960 + @Override
1.961 + public void visitReference(JCMemberReference tree) {
1.962 + scan(tree.getQualifierExpression());
1.963 + contextMap.put(tree, makeReferenceContext(tree));
1.964 + }
1.965 +
1.966 + @Override
1.967 + public void visitSelect(JCFieldAccess tree) {
1.968 + if (context() != null && lambdaSelectSymbolFilter(tree.sym)) {
1.969 + TranslationContext<?> localContext = context();
1.970 + while (localContext != null) {
1.971 + if (localContext.tree.hasTag(LAMBDA)) {
1.972 + JCClassDecl clazz = (JCClassDecl)capturedDecl(localContext.depth, tree.sym);
1.973 + if (clazz == null) break;
1.974 + ((LambdaTranslationContext)localContext).addSymbol(clazz.sym, CAPTURED_THIS);
1.975 + }
1.976 + localContext = localContext.prev;
1.977 + }
1.978 + scan(tree.selected);
1.979 + } else {
1.980 + super.visitSelect(tree);
1.981 + }
1.982 + }
1.983 +
1.984 + @Override
1.985 + public void visitVarDef(JCVariableDecl tree) {
1.986 + if (frameStack.head.tree.hasTag(LAMBDA)) {
1.987 + ((LambdaTranslationContext)context()).addSymbol(tree.sym, LOCAL_VAR);
1.988 + }
1.989 + List<Frame> prevStack = frameStack;
1.990 + try {
1.991 + if (tree.sym.owner.kind == MTH) {
1.992 + frameStack.head.addLocal(tree.sym);
1.993 + }
1.994 + frameStack = frameStack.prepend(new Frame(tree));
1.995 + super.visitVarDef(tree);
1.996 + }
1.997 + finally {
1.998 + frameStack = prevStack;
1.999 + }
1.1000 + }
1.1001 +
1.1002 + private Name lambdaName() {
1.1003 + return names.lambda.append(names.fromString("$" + lambdaCount++));
1.1004 + }
1.1005 +
1.1006 + /**
1.1007 + * Return a valid owner given the current declaration stack
1.1008 + * (required to skip synthetic lambda symbols)
1.1009 + */
1.1010 + private Symbol owner() {
1.1011 + List<Frame> frameStack2 = frameStack;
1.1012 + while (frameStack2.nonEmpty()) {
1.1013 + switch (frameStack2.head.tree.getTag()) {
1.1014 + case VARDEF:
1.1015 + if (((JCVariableDecl)frameStack2.head.tree).sym.isLocal()) {
1.1016 + frameStack2 = frameStack2.tail;
1.1017 + break;
1.1018 + }
1.1019 + JCClassDecl cdecl = (JCClassDecl)frameStack2.tail.head.tree;
1.1020 + return makeSyntheticMethod(((JCVariableDecl)frameStack2.head.tree).sym.flags() & STATIC, names.empty, null, cdecl.sym);
1.1021 + case BLOCK:
1.1022 + JCClassDecl cdecl2 = (JCClassDecl)frameStack2.tail.head.tree;
1.1023 + return makeSyntheticMethod(((JCBlock)frameStack2.head.tree).flags & STATIC | Flags.BLOCK, names.empty, null, cdecl2.sym);
1.1024 + case CLASSDEF:
1.1025 + return ((JCClassDecl)frameStack2.head.tree).sym;
1.1026 + case METHODDEF:
1.1027 + return ((JCMethodDecl)frameStack2.head.tree).sym;
1.1028 + case LAMBDA:
1.1029 + return ((LambdaTranslationContext)contextMap.get(frameStack2.head.tree)).translatedSym;
1.1030 + default:
1.1031 + frameStack2 = frameStack2.tail;
1.1032 + }
1.1033 + }
1.1034 + Assert.error();
1.1035 + return null;
1.1036 + }
1.1037 +
1.1038 + private JCTree enclosingLambda() {
1.1039 + List<Frame> frameStack2 = frameStack;
1.1040 + while (frameStack2.nonEmpty()) {
1.1041 + switch (frameStack2.head.tree.getTag()) {
1.1042 + case CLASSDEF:
1.1043 + case METHODDEF:
1.1044 + return null;
1.1045 + case LAMBDA:
1.1046 + return frameStack2.head.tree;
1.1047 + default:
1.1048 + frameStack2 = frameStack2.tail;
1.1049 + }
1.1050 + }
1.1051 + Assert.error();
1.1052 + return null;
1.1053 + }
1.1054 +
1.1055 + /**
1.1056 + * Return the declaration corresponding to a symbol in the enclosing
1.1057 + * scope; the depth parameter is used to filter out symbols defined
1.1058 + * in nested scopes (which do not need to undergo capture).
1.1059 + */
1.1060 + private JCTree capturedDecl(int depth, Symbol sym) {
1.1061 + int currentDepth = frameStack.size() - 1;
1.1062 + for (Frame block : frameStack) {
1.1063 + switch (block.tree.getTag()) {
1.1064 + case CLASSDEF:
1.1065 + ClassSymbol clazz = ((JCClassDecl)block.tree).sym;
1.1066 + if (sym.isMemberOf(clazz, types)) {
1.1067 + return currentDepth > depth ? null : block.tree;
1.1068 + }
1.1069 + break;
1.1070 + case VARDEF:
1.1071 + if (((JCVariableDecl)block.tree).sym == sym &&
1.1072 + sym.owner.kind == MTH) { //only locals are captured
1.1073 + return currentDepth > depth ? null : block.tree;
1.1074 + }
1.1075 + break;
1.1076 + case BLOCK:
1.1077 + case METHODDEF:
1.1078 + case LAMBDA:
1.1079 + if (block.locals != null && block.locals.contains(sym)) {
1.1080 + return currentDepth > depth ? null : block.tree;
1.1081 + }
1.1082 + break;
1.1083 + default:
1.1084 + Assert.error("bad decl kind " + block.tree.getTag());
1.1085 + }
1.1086 + currentDepth--;
1.1087 + }
1.1088 + return null;
1.1089 + }
1.1090 +
1.1091 + private TranslationContext<?> context() {
1.1092 + for (Frame frame : frameStack) {
1.1093 + TranslationContext<?> context = contextMap.get(frame.tree);
1.1094 + if (context != null) {
1.1095 + return context;
1.1096 + }
1.1097 + }
1.1098 + return null;
1.1099 + }
1.1100 +
1.1101 + /**
1.1102 + * This is used to filter out those identifiers that needs to be adjusted
1.1103 + * when translating away lambda expressions
1.1104 + */
1.1105 + private boolean lambdaIdentSymbolFilter(Symbol sym) {
1.1106 + return (sym.kind == VAR || sym.kind == MTH)
1.1107 + && !sym.isStatic()
1.1108 + && sym.name != names.init;
1.1109 + }
1.1110 +
1.1111 + private boolean lambdaSelectSymbolFilter(Symbol sym) {
1.1112 + return (sym.kind == VAR || sym.kind == MTH) &&
1.1113 + !sym.isStatic() &&
1.1114 + (sym.name == names._this ||
1.1115 + sym.name == names._super);
1.1116 + }
1.1117 +
1.1118 + /**
1.1119 + * This is used to filter out those new class expressions that need to
1.1120 + * be qualified with an enclosing tree
1.1121 + */
1.1122 + private boolean lambdaNewClassFilter(TranslationContext<?> context, JCNewClass tree) {
1.1123 + if (context != null
1.1124 + && tree.encl == null
1.1125 + && tree.def == null
1.1126 + && tree.type.getEnclosingType().hasTag(NONE)) {
1.1127 + Type encl = tree.type.getEnclosingType();
1.1128 + Type current = context.owner.enclClass().type;
1.1129 + while (current.hasTag(NONE)) {
1.1130 + if (current.tsym.isSubClass(encl.tsym, types)) {
1.1131 + return true;
1.1132 + }
1.1133 + current = current.getEnclosingType();
1.1134 + }
1.1135 + return false;
1.1136 + } else {
1.1137 + return false;
1.1138 + }
1.1139 + }
1.1140 +
1.1141 + private TranslationContext<JCLambda> makeLambdaContext(JCLambda tree) {
1.1142 + return new LambdaTranslationContext(tree);
1.1143 + }
1.1144 +
1.1145 + private TranslationContext<JCMemberReference> makeReferenceContext(JCMemberReference tree) {
1.1146 + return new ReferenceTranslationContext(tree);
1.1147 + }
1.1148 +
1.1149 + private class Frame {
1.1150 + final JCTree tree;
1.1151 + List<Symbol> locals;
1.1152 +
1.1153 + public Frame(JCTree tree) {
1.1154 + this.tree = tree;
1.1155 + }
1.1156 +
1.1157 + void addLocal(Symbol sym) {
1.1158 + if (locals == null) {
1.1159 + locals = List.nil();
1.1160 + }
1.1161 + locals = locals.prepend(sym);
1.1162 + }
1.1163 + }
1.1164 +
1.1165 + /**
1.1166 + * This class is used to store important information regarding translation of
1.1167 + * lambda expression/method references (see subclasses).
1.1168 + */
1.1169 + private abstract class TranslationContext<T extends JCTree> {
1.1170 +
1.1171 + /** the underlying (untranslated) tree */
1.1172 + T tree;
1.1173 +
1.1174 + /** points to the adjusted enclosing scope in which this lambda/mref expression occurs */
1.1175 + Symbol owner;
1.1176 +
1.1177 + /** the depth of this lambda expression in the frame stack */
1.1178 + int depth;
1.1179 +
1.1180 + /** the enclosing translation context (set for nested lambdas/mref) */
1.1181 + TranslationContext<?> prev;
1.1182 +
1.1183 + TranslationContext(T tree) {
1.1184 + this.tree = tree;
1.1185 + this.owner = owner();
1.1186 + this.depth = frameStack.size() - 1;
1.1187 + this.prev = context();
1.1188 + }
1.1189 + }
1.1190 +
1.1191 + /**
1.1192 + * This class retains all the useful information about a lambda expression;
1.1193 + * the contents of this class are filled by the LambdaAnalyzer visitor,
1.1194 + * and the used by the main translation routines in order to adjust references
1.1195 + * to captured locals/members, etc.
1.1196 + */
1.1197 + private class LambdaTranslationContext extends TranslationContext<JCLambda> {
1.1198 +
1.1199 + /** variable in the enclosing context to which this lambda is assigned */
1.1200 + Symbol self;
1.1201 +
1.1202 + /** map from original to translated lambda parameters */
1.1203 + Map<Symbol, Symbol> lambdaParams = new LinkedHashMap<Symbol, Symbol>();
1.1204 +
1.1205 + /** map from original to translated lambda locals */
1.1206 + Map<Symbol, Symbol> lambdaLocals = new LinkedHashMap<Symbol, Symbol>();
1.1207 +
1.1208 + /** map from variables in enclosing scope to translated synthetic parameters */
1.1209 + Map<Symbol, Symbol> capturedLocals = new LinkedHashMap<Symbol, Symbol>();
1.1210 +
1.1211 + /** map from class symbols to translated synthetic parameters (for captured member access) */
1.1212 + Map<Symbol, Symbol> capturedThis = new LinkedHashMap<Symbol, Symbol>();
1.1213 +
1.1214 + /** the synthetic symbol for the method hoisting the translated lambda */
1.1215 + Symbol translatedSym;
1.1216 +
1.1217 + List<JCVariableDecl> syntheticParams;
1.1218 +
1.1219 + LambdaTranslationContext(JCLambda tree) {
1.1220 + super(tree);
1.1221 + Frame frame = frameStack.head;
1.1222 + if (frame.tree.hasTag(VARDEF)) {
1.1223 + self = ((JCVariableDecl)frame.tree).sym;
1.1224 + }
1.1225 + this.translatedSym = makeSyntheticMethod(0, lambdaName(), null, owner.enclClass());
1.1226 + }
1.1227 +
1.1228 + /**
1.1229 + * Translate a symbol of a given kind into something suitable for the
1.1230 + * synthetic lambda body
1.1231 + */
1.1232 + Symbol translate(String name, Symbol sym, LambdaSymbolKind skind) {
1.1233 + if (skind == CAPTURED_THIS) {
1.1234 + return sym; // self represented
1.1235 + } else {
1.1236 + return makeSyntheticVar(FINAL, name, types.erasure(sym.type), translatedSym);
1.1237 + }
1.1238 + }
1.1239 +
1.1240 + void addSymbol(Symbol sym, LambdaSymbolKind skind) {
1.1241 + Map<Symbol, Symbol> transMap = null;
1.1242 + String preferredName;
1.1243 + switch (skind) {
1.1244 + case CAPTURED_THIS:
1.1245 + transMap = capturedThis;
1.1246 + preferredName = "encl$" + capturedThis.size();
1.1247 + break;
1.1248 + case CAPTURED_VAR:
1.1249 + transMap = capturedLocals;
1.1250 + preferredName = "cap$" + capturedLocals.size();
1.1251 + break;
1.1252 + case LOCAL_VAR:
1.1253 + transMap = lambdaLocals;
1.1254 + preferredName = sym.name.toString();
1.1255 + break;
1.1256 + case PARAM:
1.1257 + transMap = lambdaParams;
1.1258 + preferredName = sym.name.toString();
1.1259 + break;
1.1260 + default: throw new AssertionError();
1.1261 + }
1.1262 + if (!transMap.containsKey(sym)) {
1.1263 + transMap.put(sym, translate(preferredName, sym, skind));
1.1264 + }
1.1265 + }
1.1266 +
1.1267 + Map<Symbol, Symbol> getSymbolMap(LambdaSymbolKind... skinds) {
1.1268 + LinkedHashMap<Symbol, Symbol> translationMap = new LinkedHashMap<Symbol, Symbol>();
1.1269 + for (LambdaSymbolKind skind : skinds) {
1.1270 + switch (skind) {
1.1271 + case CAPTURED_THIS:
1.1272 + translationMap.putAll(capturedThis);
1.1273 + break;
1.1274 + case CAPTURED_VAR:
1.1275 + translationMap.putAll(capturedLocals);
1.1276 + break;
1.1277 + case LOCAL_VAR:
1.1278 + translationMap.putAll(lambdaLocals);
1.1279 + break;
1.1280 + case PARAM:
1.1281 + translationMap.putAll(lambdaParams);
1.1282 + break;
1.1283 + default: throw new AssertionError();
1.1284 + }
1.1285 + }
1.1286 + return translationMap;
1.1287 + }
1.1288 +
1.1289 + /**
1.1290 + * The translatedSym is not complete/accurate until the analysis is
1.1291 + * finished. Once the analysis is finished, the translatedSym is
1.1292 + * "completed" -- updated with type information, access modifiers,
1.1293 + * and full parameter list.
1.1294 + */
1.1295 + void complete() {
1.1296 + if (syntheticParams != null) {
1.1297 + return;
1.1298 + }
1.1299 + boolean inInterface = translatedSym.owner.isInterface();
1.1300 + boolean thisReferenced = !getSymbolMap(CAPTURED_THIS).isEmpty();
1.1301 + boolean needInstance = thisReferenced || inInterface;
1.1302 +
1.1303 + // If instance access isn't needed, make it static
1.1304 + // Interface methods much be public default methods, otherwise make it private
1.1305 + translatedSym.flags_field = SYNTHETIC | (needInstance? 0 : STATIC) | (inInterface? PUBLIC | DEFAULT : PRIVATE);
1.1306 +
1.1307 + //compute synthetic params
1.1308 + ListBuffer<JCVariableDecl> params = ListBuffer.lb();
1.1309 +
1.1310 + // The signature of the method is augmented with the following
1.1311 + // synthetic parameters:
1.1312 + //
1.1313 + // 1) reference to enclosing contexts captured by the lambda expression
1.1314 + // 2) enclosing locals captured by the lambda expression
1.1315 + for (Symbol thisSym : getSymbolMap(CAPTURED_VAR, PARAM).values()) {
1.1316 + params.append(make.VarDef((VarSymbol) thisSym, null));
1.1317 + }
1.1318 +
1.1319 + syntheticParams = params.toList();
1.1320 +
1.1321 + //prepend synthetic args to translated lambda method signature
1.1322 + translatedSym.type = (MethodType) types.createMethodTypeWithParameters(
1.1323 + (MethodType) generatedLambdaSig(),
1.1324 + TreeInfo.types(syntheticParams));
1.1325 + }
1.1326 +
1.1327 + Type enclosingType() {
1.1328 + //local inner classes defined inside a lambda are always non-static
1.1329 + return owner.enclClass().type;
1.1330 + }
1.1331 +
1.1332 + Type generatedLambdaSig() {
1.1333 + return types.erasure(types.findDescriptorType(tree.targetType));
1.1334 + }
1.1335 + }
1.1336 +
1.1337 + /**
1.1338 + * This class retains all the useful information about a method reference;
1.1339 + * the contents of this class are filled by the LambdaAnalyzer visitor,
1.1340 + * and the used by the main translation routines in order to adjust method
1.1341 + * references (i.e. in case a bridge is needed)
1.1342 + */
1.1343 + private class ReferenceTranslationContext extends TranslationContext<JCMemberReference> {
1.1344 +
1.1345 + final boolean isSuper;
1.1346 + final Symbol bridgeSym;
1.1347 +
1.1348 + ReferenceTranslationContext(JCMemberReference tree) {
1.1349 + super(tree);
1.1350 + this.isSuper = tree.hasKind(ReferenceKind.SUPER);
1.1351 + this.bridgeSym = needsBridge()
1.1352 + ? makeSyntheticMethod(isSuper ? 0 : STATIC,
1.1353 + lambdaName().append(names.fromString("$bridge")), null,
1.1354 + owner.enclClass())
1.1355 + : null;
1.1356 + }
1.1357 +
1.1358 + /**
1.1359 + * Get the opcode associated with this method reference
1.1360 + */
1.1361 + int referenceKind() {
1.1362 + return LambdaToMethod.this.referenceKind(needsBridge() ? bridgeSym : tree.sym);
1.1363 + }
1.1364 +
1.1365 + boolean needsVarArgsConversion() {
1.1366 + return tree.varargsElement != null;
1.1367 + }
1.1368 +
1.1369 + /**
1.1370 + * @return Is this an array operation like clone()
1.1371 + */
1.1372 + boolean isArrayOp() {
1.1373 + return tree.sym.owner == syms.arrayClass;
1.1374 + }
1.1375 +
1.1376 + /**
1.1377 + * Does this reference needs a bridge (i.e. var args need to be
1.1378 + * expanded or "super" is used)
1.1379 + */
1.1380 + final boolean needsBridge() {
1.1381 + return isSuper || needsVarArgsConversion() || isArrayOp();
1.1382 + }
1.1383 +
1.1384 + Type generatedRefSig() {
1.1385 + return types.erasure(tree.sym.type);
1.1386 + }
1.1387 +
1.1388 + Type bridgedRefSig() {
1.1389 + return types.erasure(types.findDescriptorSymbol(tree.targetType.tsym).type);
1.1390 + }
1.1391 + }
1.1392 + }
1.1393 + // </editor-fold>
1.1394 +
1.1395 + enum LambdaSymbolKind {
1.1396 + CAPTURED_VAR,
1.1397 + CAPTURED_THIS,
1.1398 + LOCAL_VAR,
1.1399 + PARAM;
1.1400 + }
1.1401 +}
