Enter.java revision 4202:2bd34895dda2
1/* 2 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package com.sun.tools.javac.comp; 27 28import java.util.Map; 29import java.util.Optional; 30 31import javax.tools.JavaFileObject; 32import javax.tools.JavaFileManager; 33 34import com.sun.tools.javac.code.*; 35import com.sun.tools.javac.code.Kinds.KindName; 36import com.sun.tools.javac.code.Kinds.KindSelector; 37import com.sun.tools.javac.code.Scope.*; 38import com.sun.tools.javac.code.Symbol.*; 39import com.sun.tools.javac.code.Type.*; 40import com.sun.tools.javac.main.Option.PkgInfo; 41import com.sun.tools.javac.resources.CompilerProperties.Errors; 42import com.sun.tools.javac.resources.CompilerProperties.Warnings; 43import com.sun.tools.javac.tree.*; 44import com.sun.tools.javac.tree.JCTree.*; 45import com.sun.tools.javac.util.*; 46import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 47import com.sun.tools.javac.util.List; 48 49import static com.sun.tools.javac.code.Flags.*; 50import static com.sun.tools.javac.code.Kinds.Kind.*; 51 52/** This class enters symbols for all encountered definitions into 53 * the symbol table. The pass consists of high-level two phases, 54 * organized as follows: 55 * 56 * <p>In the first phase, all class symbols are entered into their 57 * enclosing scope, descending recursively down the tree for classes 58 * which are members of other classes. The class symbols are given a 59 * TypeEnter object as completer. 60 * 61 * <p>In the second phase classes are completed using 62 * TypeEnter.complete(). Completion might occur on demand, but 63 * any classes that are not completed that way will be eventually 64 * completed by processing the `uncompleted' queue. Completion 65 * entails determination of a class's parameters, supertype and 66 * interfaces, as well as entering all symbols defined in the 67 * class into its scope, with the exception of class symbols which 68 * have been entered in phase 1. 69 * 70 * <p>Whereas the first phase is organized as a sweep through all 71 * compiled syntax trees, the second phase is on-demand. Members of a 72 * class are entered when the contents of a class are first 73 * accessed. This is accomplished by installing completer objects in 74 * class symbols for compiled classes which invoke the type-enter 75 * phase for the corresponding class tree. 76 * 77 * <p>Classes migrate from one phase to the next via queues: 78 * 79 * <pre>{@literal 80 * class enter -> (Enter.uncompleted) --> type enter 81 * -> (Todo) --> attribute 82 * (only for toplevel classes) 83 * }</pre> 84 * 85 * <p><b>This is NOT part of any supported API. 86 * If you write code that depends on this, you do so at your own risk. 87 * This code and its internal interfaces are subject to change or 88 * deletion without notice.</b> 89 */ 90public class Enter extends JCTree.Visitor { 91 protected static final Context.Key<Enter> enterKey = new Context.Key<>(); 92 93 Annotate annotate; 94 Log log; 95 Symtab syms; 96 Check chk; 97 TreeMaker make; 98 TypeEnter typeEnter; 99 Types types; 100 Lint lint; 101 Names names; 102 JavaFileManager fileManager; 103 PkgInfo pkginfoOpt; 104 TypeEnvs typeEnvs; 105 Modules modules; 106 JCDiagnostic.Factory diags; 107 108 private final Todo todo; 109 110 public static Enter instance(Context context) { 111 Enter instance = context.get(enterKey); 112 if (instance == null) 113 instance = new Enter(context); 114 return instance; 115 } 116 117 protected Enter(Context context) { 118 context.put(enterKey, this); 119 120 log = Log.instance(context); 121 make = TreeMaker.instance(context); 122 syms = Symtab.instance(context); 123 chk = Check.instance(context); 124 typeEnter = TypeEnter.instance(context); 125 types = Types.instance(context); 126 annotate = Annotate.instance(context); 127 lint = Lint.instance(context); 128 names = Names.instance(context); 129 modules = Modules.instance(context); 130 diags = JCDiagnostic.Factory.instance(context); 131 132 predefClassDef = make.ClassDef( 133 make.Modifiers(PUBLIC), 134 syms.predefClass.name, 135 List.nil(), 136 null, 137 List.nil(), 138 List.nil()); 139 predefClassDef.sym = syms.predefClass; 140 todo = Todo.instance(context); 141 fileManager = context.get(JavaFileManager.class); 142 143 Options options = Options.instance(context); 144 pkginfoOpt = PkgInfo.get(options); 145 typeEnvs = TypeEnvs.instance(context); 146 } 147 148 /** Accessor for typeEnvs 149 */ 150 public Env<AttrContext> getEnv(TypeSymbol sym) { 151 return typeEnvs.get(sym); 152 } 153 154 public Iterable<Env<AttrContext>> getEnvs() { 155 return typeEnvs.values(); 156 } 157 158 public Env<AttrContext> getClassEnv(TypeSymbol sym) { 159 Env<AttrContext> localEnv = getEnv(sym); 160 if (localEnv == null) return null; 161 Env<AttrContext> lintEnv = localEnv; 162 while (lintEnv.info.lint == null) 163 lintEnv = lintEnv.next; 164 localEnv.info.lint = lintEnv.info.lint.augment(sym); 165 return localEnv; 166 } 167 168 /** The queue of all classes that might still need to be completed; 169 * saved and initialized by main(). 170 */ 171 ListBuffer<ClassSymbol> uncompleted; 172 173 /** The queue of modules whose imports still need to be checked. */ 174 ListBuffer<JCCompilationUnit> unfinishedModules = new ListBuffer<>(); 175 176 /** A dummy class to serve as enclClass for toplevel environments. 177 */ 178 private JCClassDecl predefClassDef; 179 180/* ************************************************************************ 181 * environment construction 182 *************************************************************************/ 183 184 185 /** Create a fresh environment for class bodies. 186 * This will create a fresh scope for local symbols of a class, referred 187 * to by the environments info.scope field. 188 * This scope will contain 189 * - symbols for this and super 190 * - symbols for any type parameters 191 * In addition, it serves as an anchor for scopes of methods and initializers 192 * which are nested in this scope via Scope.dup(). 193 * This scope should not be confused with the members scope of a class. 194 * 195 * @param tree The class definition. 196 * @param env The environment current outside of the class definition. 197 */ 198 public Env<AttrContext> classEnv(JCClassDecl tree, Env<AttrContext> env) { 199 Env<AttrContext> localEnv = 200 env.dup(tree, env.info.dup(WriteableScope.create(tree.sym))); 201 localEnv.enclClass = tree; 202 localEnv.outer = env; 203 localEnv.info.isSelfCall = false; 204 localEnv.info.lint = null; // leave this to be filled in by Attr, 205 // when annotations have been processed 206 localEnv.info.isAnonymousDiamond = TreeInfo.isDiamond(env.tree); 207 return localEnv; 208 } 209 210 /** Create a fresh environment for toplevels. 211 * @param tree The toplevel tree. 212 */ 213 Env<AttrContext> topLevelEnv(JCCompilationUnit tree) { 214 Env<AttrContext> localEnv = new Env<>(tree, new AttrContext()); 215 localEnv.toplevel = tree; 216 localEnv.enclClass = predefClassDef; 217 tree.toplevelScope = WriteableScope.create(tree.packge); 218 tree.namedImportScope = new NamedImportScope(tree.packge, tree.toplevelScope); 219 tree.starImportScope = new StarImportScope(tree.packge); 220 localEnv.info.scope = tree.toplevelScope; 221 localEnv.info.lint = lint; 222 return localEnv; 223 } 224 225 public Env<AttrContext> getTopLevelEnv(JCCompilationUnit tree) { 226 Env<AttrContext> localEnv = new Env<>(tree, new AttrContext()); 227 localEnv.toplevel = tree; 228 localEnv.enclClass = predefClassDef; 229 localEnv.info.scope = tree.toplevelScope; 230 localEnv.info.lint = lint; 231 return localEnv; 232 } 233 234 /** The scope in which a member definition in environment env is to be entered 235 * This is usually the environment's scope, except for class environments, 236 * where the local scope is for type variables, and the this and super symbol 237 * only, and members go into the class member scope. 238 */ 239 WriteableScope enterScope(Env<AttrContext> env) { 240 return (env.tree.hasTag(JCTree.Tag.CLASSDEF)) 241 ? ((JCClassDecl) env.tree).sym.members_field 242 : env.info.scope; 243 } 244 245 /** Create a fresh environment for modules. 246 * 247 * @param tree The module definition. 248 * @param env The environment current outside of the module definition. 249 */ 250 public Env<AttrContext> moduleEnv(JCModuleDecl tree, Env<AttrContext> env) { 251 Assert.checkNonNull(tree.sym); 252 Env<AttrContext> localEnv = 253 env.dup(tree, env.info.dup(WriteableScope.create(tree.sym))); 254 localEnv.enclClass = predefClassDef; 255 localEnv.outer = env; 256 localEnv.info.isSelfCall = false; 257 localEnv.info.lint = null; // leave this to be filled in by Attr, 258 // when annotations have been processed 259 return localEnv; 260 } 261 262 263/* ************************************************************************ 264 * Visitor methods for phase 1: class enter 265 *************************************************************************/ 266 267 /** Visitor argument: the current environment. 268 */ 269 protected Env<AttrContext> env; 270 271 /** Visitor result: the computed type. 272 */ 273 Type result; 274 275 /** Visitor method: enter all classes in given tree, catching any 276 * completion failure exceptions. Return the tree's type. 277 * 278 * @param tree The tree to be visited. 279 * @param env The environment visitor argument. 280 */ 281 Type classEnter(JCTree tree, Env<AttrContext> env) { 282 Env<AttrContext> prevEnv = this.env; 283 try { 284 this.env = env; 285 annotate.blockAnnotations(); 286 tree.accept(this); 287 return result; 288 } catch (CompletionFailure ex) { 289 return chk.completionError(tree.pos(), ex); 290 } finally { 291 annotate.unblockAnnotations(); 292 this.env = prevEnv; 293 } 294 } 295 296 /** Visitor method: enter classes of a list of trees, returning a list of types. 297 */ 298 <T extends JCTree> List<Type> classEnter(List<T> trees, Env<AttrContext> env) { 299 ListBuffer<Type> ts = new ListBuffer<>(); 300 for (List<T> l = trees; l.nonEmpty(); l = l.tail) { 301 Type t = classEnter(l.head, env); 302 if (t != null) 303 ts.append(t); 304 } 305 return ts.toList(); 306 } 307 308 @Override 309 public void visitTopLevel(JCCompilationUnit tree) { 310// Assert.checkNonNull(tree.modle, tree.sourcefile.toString()); 311 312 JavaFileObject prev = log.useSource(tree.sourcefile); 313 boolean addEnv = false; 314 boolean isPkgInfo = tree.sourcefile.isNameCompatible("package-info", 315 JavaFileObject.Kind.SOURCE); 316 if (TreeInfo.isModuleInfo(tree)) { 317 JCPackageDecl pd = tree.getPackage(); 318 if (pd != null) { 319 log.error(pd.pos(), Errors.NoPkgInModuleInfoJava); 320 } 321 tree.packge = syms.rootPackage; 322 Env<AttrContext> topEnv = topLevelEnv(tree); 323 classEnter(tree.defs, topEnv); 324 tree.modle.usesProvidesCompleter = modules.getUsesProvidesCompleter(); 325 } else { 326 JCPackageDecl pd = tree.getPackage(); 327 if (pd != null) { 328 tree.packge = pd.packge = syms.enterPackage(tree.modle, TreeInfo.fullName(pd.pid)); 329 if ( pd.annotations.nonEmpty() 330 || pkginfoOpt == PkgInfo.ALWAYS 331 || tree.docComments != null) { 332 if (isPkgInfo) { 333 addEnv = true; 334 } else if (pd.annotations.nonEmpty()) { 335 log.error(pd.annotations.head.pos(), 336 Errors.PkgAnnotationsSbInPackageInfoJava); 337 } 338 } 339 } else { 340 tree.packge = tree.modle.unnamedPackage; 341 } 342 343 Map<Name, PackageSymbol> visiblePackages = tree.modle.visiblePackages; 344 Optional<ModuleSymbol> dependencyWithPackage = 345 syms.listPackageModules(tree.packge.fullname) 346 .stream() 347 .filter(m -> m != tree.modle) 348 .filter(cand -> visiblePackages.get(tree.packge.fullname) == syms.getPackage(cand, tree.packge.fullname)) 349 .findAny(); 350 351 if (dependencyWithPackage.isPresent()) { 352 log.error(pd, Errors.PackageInOtherModule(dependencyWithPackage.get())); 353 } 354 355 tree.packge.complete(); // Find all classes in package. 356 357 Env<AttrContext> topEnv = topLevelEnv(tree); 358 Env<AttrContext> packageEnv = isPkgInfo ? topEnv.dup(pd) : null; 359 360 // Save environment of package-info.java file. 361 if (isPkgInfo) { 362 Env<AttrContext> env0 = typeEnvs.get(tree.packge); 363 if (env0 != null) { 364 JCCompilationUnit tree0 = env0.toplevel; 365 if (!fileManager.isSameFile(tree.sourcefile, tree0.sourcefile)) { 366 log.warning(pd != null ? pd.pid.pos() : null, 367 Warnings.PkgInfoAlreadySeen(tree.packge)); 368 } 369 } 370 typeEnvs.put(tree.packge, packageEnv); 371 372 for (Symbol q = tree.packge; q != null && q.kind == PCK; q = q.owner) 373 q.flags_field |= EXISTS; 374 375 Name name = names.package_info; 376 ClassSymbol c = syms.enterClass(tree.modle, name, tree.packge); 377 c.flatname = names.fromString(tree.packge + "." + name); 378 c.sourcefile = tree.sourcefile; 379 c.completer = Completer.NULL_COMPLETER; 380 c.members_field = WriteableScope.create(c); 381 tree.packge.package_info = c; 382 } 383 classEnter(tree.defs, topEnv); 384 if (addEnv) { 385 todo.append(packageEnv); 386 } 387 } 388 log.useSource(prev); 389 result = null; 390 } 391 392 @Override 393 public void visitClassDef(JCClassDecl tree) { 394 Symbol owner = env.info.scope.owner; 395 WriteableScope enclScope = enterScope(env); 396 ClassSymbol c; 397 if (owner.kind == PCK) { 398 // We are seeing a toplevel class. 399 PackageSymbol packge = (PackageSymbol)owner; 400 for (Symbol q = packge; q != null && q.kind == PCK; q = q.owner) 401 q.flags_field |= EXISTS; 402 c = syms.enterClass(env.toplevel.modle, tree.name, packge); 403 packge.members().enterIfAbsent(c); 404 if ((tree.mods.flags & PUBLIC) != 0 && !classNameMatchesFileName(c, env)) { 405 KindName topElement = KindName.CLASS; 406 if ((tree.mods.flags & ENUM) != 0) { 407 topElement = KindName.ENUM; 408 } else if ((tree.mods.flags & INTERFACE) != 0) { 409 topElement = KindName.INTERFACE; 410 } 411 log.error(tree.pos(), 412 Errors.ClassPublicShouldBeInFile(topElement, tree.name)); 413 } 414 } else { 415 if (!tree.name.isEmpty() && 416 !chk.checkUniqueClassName(tree.pos(), tree.name, enclScope)) { 417 result = null; 418 return; 419 } 420 if (owner.kind == TYP) { 421 // We are seeing a member class. 422 c = syms.enterClass(env.toplevel.modle, tree.name, (TypeSymbol)owner); 423 if (c.owner != owner) { 424 //anonymous class loaded from a classfile may be recreated from source (see below) 425 //if this class is a member of such an anonymous class, fix the owner: 426 Assert.check(owner.owner.kind != TYP, owner::toString); 427 Assert.check(c.owner.kind == TYP, () -> c.owner.toString()); 428 ClassSymbol cowner = (ClassSymbol) c.owner; 429 if (cowner.members_field != null) { 430 cowner.members_field.remove(c); 431 } 432 c.owner = owner; 433 } 434 if ((owner.flags_field & INTERFACE) != 0) { 435 tree.mods.flags |= PUBLIC | STATIC; 436 } 437 } else { 438 // We are seeing a local class. 439 c = syms.defineClass(tree.name, owner); 440 c.flatname = chk.localClassName(c); 441 if (!c.name.isEmpty()) 442 chk.checkTransparentClass(tree.pos(), c, env.info.scope); 443 } 444 } 445 tree.sym = c; 446 447 // Enter class into `compiled' table and enclosing scope. 448 if (chk.getCompiled(c) != null) { 449 duplicateClass(tree.pos(), c); 450 result = types.createErrorType(tree.name, (TypeSymbol)owner, Type.noType); 451 tree.sym = (ClassSymbol)result.tsym; 452 return; 453 } 454 chk.putCompiled(c); 455 enclScope.enter(c); 456 457 // Set up an environment for class block and store in `typeEnvs' 458 // table, to be retrieved later in memberEnter and attribution. 459 Env<AttrContext> localEnv = classEnv(tree, env); 460 typeEnvs.put(c, localEnv); 461 462 // Fill out class fields. 463 c.completer = Completer.NULL_COMPLETER; // do not allow the initial completer linger on. 464 c.flags_field = chk.checkFlags(tree.pos(), tree.mods.flags, c, tree); 465 c.sourcefile = env.toplevel.sourcefile; 466 c.members_field = WriteableScope.create(c); 467 c.clearAnnotationMetadata(); 468 469 ClassType ct = (ClassType)c.type; 470 if (owner.kind != PCK && (c.flags_field & STATIC) == 0) { 471 // We are seeing a local or inner class. 472 // Set outer_field of this class to closest enclosing class 473 // which contains this class in a non-static context 474 // (its "enclosing instance class"), provided such a class exists. 475 Symbol owner1 = owner; 476 while (owner1.kind.matches(KindSelector.VAL_MTH) && 477 (owner1.flags_field & STATIC) == 0) { 478 owner1 = owner1.owner; 479 } 480 if (owner1.kind == TYP) { 481 ct.setEnclosingType(owner1.type); 482 } 483 } 484 485 // Enter type parameters. 486 ct.typarams_field = classEnter(tree.typarams, localEnv); 487 ct.allparams_field = null; 488 489 // install further completer for this type. 490 c.completer = typeEnter; 491 492 // Add non-local class to uncompleted, to make sure it will be 493 // completed later. 494 if (!c.isLocal() && uncompleted != null) uncompleted.append(c); 495// System.err.println("entering " + c.fullname + " in " + c.owner);//DEBUG 496 497 // Recursively enter all member classes. 498 classEnter(tree.defs, localEnv); 499 500// Assert.checkNonNull(c.modle, c.sourcefile.toString()); 501 502 result = c.type; 503 } 504 //where 505 /** Does class have the same name as the file it appears in? 506 */ 507 private static boolean classNameMatchesFileName(ClassSymbol c, 508 Env<AttrContext> env) { 509 return env.toplevel.sourcefile.isNameCompatible(c.name.toString(), 510 JavaFileObject.Kind.SOURCE); 511 } 512 513 /** Complain about a duplicate class. */ 514 protected void duplicateClass(DiagnosticPosition pos, ClassSymbol c) { 515 log.error(pos, Errors.DuplicateClass(c.fullname)); 516 } 517 518 /** Class enter visitor method for type parameters. 519 * Enter a symbol for type parameter in local scope, after checking that it 520 * is unique. 521 */ 522 @Override 523 public void visitTypeParameter(JCTypeParameter tree) { 524 TypeVar a = (tree.type != null) 525 ? (TypeVar)tree.type 526 : new TypeVar(tree.name, env.info.scope.owner, syms.botType); 527 tree.type = a; 528 if (chk.checkUnique(tree.pos(), a.tsym, env.info.scope)) { 529 env.info.scope.enter(a.tsym); 530 } 531 result = a; 532 } 533 534 @Override 535 public void visitModuleDef(JCModuleDecl tree) { 536 Env<AttrContext> moduleEnv = moduleEnv(tree, env); 537 typeEnvs.put(tree.sym, moduleEnv); 538 if (modules.isInModuleGraph(tree.sym)) { 539 todo.append(moduleEnv); 540 } 541 } 542 543 /** Default class enter visitor method: do nothing. 544 */ 545 @Override 546 public void visitTree(JCTree tree) { 547 result = null; 548 } 549 550 /** Main method: enter all classes in a list of toplevel trees. 551 * @param trees The list of trees to be processed. 552 */ 553 public void main(List<JCCompilationUnit> trees) { 554 complete(trees, null); 555 } 556 557 /** Main method: enter classes from the list of toplevel trees, possibly 558 * skipping TypeEnter for all but 'c' by placing them on the uncompleted 559 * list. 560 * @param trees The list of trees to be processed. 561 * @param c The class symbol to be processed or null to process all. 562 */ 563 public void complete(List<JCCompilationUnit> trees, ClassSymbol c) { 564 annotate.blockAnnotations(); 565 ListBuffer<ClassSymbol> prevUncompleted = uncompleted; 566 if (typeEnter.completionEnabled) uncompleted = new ListBuffer<>(); 567 568 try { 569 // enter all classes, and construct uncompleted list 570 classEnter(trees, null); 571 572 // complete all uncompleted classes in memberEnter 573 if (typeEnter.completionEnabled) { 574 while (uncompleted.nonEmpty()) { 575 ClassSymbol clazz = uncompleted.next(); 576 if (c == null || c == clazz || prevUncompleted == null) 577 clazz.complete(); 578 else 579 // defer 580 prevUncompleted.append(clazz); 581 } 582 583 if (!modules.modulesInitialized()) { 584 for (JCCompilationUnit cut : trees) { 585 if (cut.getModuleDecl() != null) { 586 unfinishedModules.append(cut); 587 } else { 588 typeEnter.ensureImportsChecked(List.of(cut)); 589 } 590 } 591 } else { 592 typeEnter.ensureImportsChecked(unfinishedModules.toList()); 593 unfinishedModules.clear(); 594 typeEnter.ensureImportsChecked(trees); 595 } 596 } 597 } finally { 598 uncompleted = prevUncompleted; 599 annotate.unblockAnnotations(); 600 } 601 } 602 603 public void newRound() { 604 typeEnvs.clear(); 605 } 606} 607