Enter.java revision 3796:031db713312f
1/* 2 * Copyright (c) 1999, 2016, 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.KindSelector; 36import com.sun.tools.javac.code.Scope.*; 37import com.sun.tools.javac.code.Symbol.*; 38import com.sun.tools.javac.code.Type.*; 39import com.sun.tools.javac.main.Option.PkgInfo; 40import com.sun.tools.javac.resources.CompilerProperties.Errors; 41import com.sun.tools.javac.tree.*; 42import com.sun.tools.javac.tree.JCTree.*; 43import com.sun.tools.javac.util.*; 44import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 45import com.sun.tools.javac.util.List; 46 47import static com.sun.tools.javac.code.Flags.*; 48import static com.sun.tools.javac.code.Kinds.Kind.*; 49 50/** This class enters symbols for all encountered definitions into 51 * the symbol table. The pass consists of high-level two phases, 52 * organized as follows: 53 * 54 * <p>In the first phase, all class symbols are entered into their 55 * enclosing scope, descending recursively down the tree for classes 56 * which are members of other classes. The class symbols are given a 57 * TypeEnter object as completer. 58 * 59 * <p>In the second phase classes are completed using 60 * TypeEnter.complete(). Completion might occur on demand, but 61 * any classes that are not completed that way will be eventually 62 * completed by processing the `uncompleted' queue. Completion 63 * entails determination of a class's parameters, supertype and 64 * interfaces, as well as entering all symbols defined in the 65 * class into its scope, with the exception of class symbols which 66 * have been entered in phase 1. 67 * 68 * <p>Whereas the first phase is organized as a sweep through all 69 * compiled syntax trees, the second phase is on-demand. Members of a 70 * class are entered when the contents of a class are first 71 * accessed. This is accomplished by installing completer objects in 72 * class symbols for compiled classes which invoke the type-enter 73 * phase for the corresponding class tree. 74 * 75 * <p>Classes migrate from one phase to the next via queues: 76 * 77 * <pre>{@literal 78 * class enter -> (Enter.uncompleted) --> type enter 79 * -> (Todo) --> attribute 80 * (only for toplevel classes) 81 * }</pre> 82 * 83 * <p><b>This is NOT part of any supported API. 84 * If you write code that depends on this, you do so at your own risk. 85 * This code and its internal interfaces are subject to change or 86 * deletion without notice.</b> 87 */ 88public class Enter extends JCTree.Visitor { 89 protected static final Context.Key<Enter> enterKey = new Context.Key<>(); 90 91 Annotate annotate; 92 Log log; 93 Symtab syms; 94 Check chk; 95 TreeMaker make; 96 TypeEnter typeEnter; 97 Types types; 98 Lint lint; 99 Names names; 100 JavaFileManager fileManager; 101 PkgInfo pkginfoOpt; 102 TypeEnvs typeEnvs; 103 Modules modules; 104 JCDiagnostic.Factory diags; 105 106 private final Todo todo; 107 108 public static Enter instance(Context context) { 109 Enter instance = context.get(enterKey); 110 if (instance == null) 111 instance = new Enter(context); 112 return instance; 113 } 114 115 protected Enter(Context context) { 116 context.put(enterKey, this); 117 118 log = Log.instance(context); 119 make = TreeMaker.instance(context); 120 syms = Symtab.instance(context); 121 chk = Check.instance(context); 122 typeEnter = TypeEnter.instance(context); 123 types = Types.instance(context); 124 annotate = Annotate.instance(context); 125 lint = Lint.instance(context); 126 names = Names.instance(context); 127 modules = Modules.instance(context); 128 diags = JCDiagnostic.Factory.instance(context); 129 130 predefClassDef = make.ClassDef( 131 make.Modifiers(PUBLIC), 132 syms.predefClass.name, 133 List.<JCTypeParameter>nil(), 134 null, 135 List.<JCExpression>nil(), 136 List.<JCTree>nil()); 137 predefClassDef.sym = syms.predefClass; 138 todo = Todo.instance(context); 139 fileManager = context.get(JavaFileManager.class); 140 141 Options options = Options.instance(context); 142 pkginfoOpt = PkgInfo.get(options); 143 typeEnvs = TypeEnvs.instance(context); 144 } 145 146 /** Accessor for typeEnvs 147 */ 148 public Env<AttrContext> getEnv(TypeSymbol sym) { 149 return typeEnvs.get(sym); 150 } 151 152 public Iterable<Env<AttrContext>> getEnvs() { 153 return typeEnvs.values(); 154 } 155 156 public Env<AttrContext> getClassEnv(TypeSymbol sym) { 157 Env<AttrContext> localEnv = getEnv(sym); 158 Env<AttrContext> lintEnv = localEnv; 159 while (lintEnv.info.lint == null) 160 lintEnv = lintEnv.next; 161 localEnv.info.lint = lintEnv.info.lint.augment(sym); 162 return localEnv; 163 } 164 165 /** The queue of all classes that might still need to be completed; 166 * saved and initialized by main(). 167 */ 168 ListBuffer<ClassSymbol> uncompleted; 169 170 /** The queue of modules whose imports still need to be checked. */ 171 ListBuffer<JCCompilationUnit> unfinishedModules = new ListBuffer<>(); 172 173 /** A dummy class to serve as enclClass for toplevel environments. 174 */ 175 private JCClassDecl predefClassDef; 176 177/* ************************************************************************ 178 * environment construction 179 *************************************************************************/ 180 181 182 /** Create a fresh environment for class bodies. 183 * This will create a fresh scope for local symbols of a class, referred 184 * to by the environments info.scope field. 185 * This scope will contain 186 * - symbols for this and super 187 * - symbols for any type parameters 188 * In addition, it serves as an anchor for scopes of methods and initializers 189 * which are nested in this scope via Scope.dup(). 190 * This scope should not be confused with the members scope of a class. 191 * 192 * @param tree The class definition. 193 * @param env The environment current outside of the class definition. 194 */ 195 public Env<AttrContext> classEnv(JCClassDecl tree, Env<AttrContext> env) { 196 Env<AttrContext> localEnv = 197 env.dup(tree, env.info.dup(WriteableScope.create(tree.sym))); 198 localEnv.enclClass = tree; 199 localEnv.outer = env; 200 localEnv.info.isSelfCall = false; 201 localEnv.info.lint = null; // leave this to be filled in by Attr, 202 // when annotations have been processed 203 localEnv.info.isAnonymousDiamond = TreeInfo.isDiamond(env.tree); 204 return localEnv; 205 } 206 207 /** Create a fresh environment for toplevels. 208 * @param tree The toplevel tree. 209 */ 210 Env<AttrContext> topLevelEnv(JCCompilationUnit tree) { 211 Env<AttrContext> localEnv = new Env<>(tree, new AttrContext()); 212 localEnv.toplevel = tree; 213 localEnv.enclClass = predefClassDef; 214 tree.toplevelScope = WriteableScope.create(tree.packge); 215 tree.namedImportScope = new NamedImportScope(tree.packge, tree.toplevelScope); 216 tree.starImportScope = new StarImportScope(tree.packge); 217 localEnv.info.scope = tree.toplevelScope; 218 localEnv.info.lint = lint; 219 return localEnv; 220 } 221 222 public Env<AttrContext> getTopLevelEnv(JCCompilationUnit tree) { 223 Env<AttrContext> localEnv = new Env<>(tree, new AttrContext()); 224 localEnv.toplevel = tree; 225 localEnv.enclClass = predefClassDef; 226 localEnv.info.scope = tree.toplevelScope; 227 localEnv.info.lint = lint; 228 return localEnv; 229 } 230 231 /** The scope in which a member definition in environment env is to be entered 232 * This is usually the environment's scope, except for class environments, 233 * where the local scope is for type variables, and the this and super symbol 234 * only, and members go into the class member scope. 235 */ 236 WriteableScope enterScope(Env<AttrContext> env) { 237 return (env.tree.hasTag(JCTree.Tag.CLASSDEF)) 238 ? ((JCClassDecl) env.tree).sym.members_field 239 : env.info.scope; 240 } 241 242 /** Create a fresh environment for modules. 243 * 244 * @param tree The module definition. 245 * @param env The environment current outside of the module definition. 246 */ 247 public Env<AttrContext> moduleEnv(JCModuleDecl tree, Env<AttrContext> env) { 248 Assert.checkNonNull(tree.sym); 249 Env<AttrContext> localEnv = 250 env.dup(tree, env.info.dup(WriteableScope.create(tree.sym))); 251 localEnv.enclClass = predefClassDef; 252 localEnv.outer = env; 253 localEnv.info.isSelfCall = false; 254 localEnv.info.lint = null; // leave this to be filled in by Attr, 255 // when annotations have been processed 256 return localEnv; 257 } 258 259 260/* ************************************************************************ 261 * Visitor methods for phase 1: class enter 262 *************************************************************************/ 263 264 /** Visitor argument: the current environment. 265 */ 266 protected Env<AttrContext> env; 267 268 /** Visitor result: the computed type. 269 */ 270 Type result; 271 272 /** Visitor method: enter all classes in given tree, catching any 273 * completion failure exceptions. Return the tree's type. 274 * 275 * @param tree The tree to be visited. 276 * @param env The environment visitor argument. 277 */ 278 Type classEnter(JCTree tree, Env<AttrContext> env) { 279 Env<AttrContext> prevEnv = this.env; 280 try { 281 this.env = env; 282 annotate.blockAnnotations(); 283 tree.accept(this); 284 return result; 285 } catch (CompletionFailure ex) { 286 return chk.completionError(tree.pos(), ex); 287 } finally { 288 annotate.unblockAnnotations(); 289 this.env = prevEnv; 290 } 291 } 292 293 /** Visitor method: enter classes of a list of trees, returning a list of types. 294 */ 295 <T extends JCTree> List<Type> classEnter(List<T> trees, Env<AttrContext> env) { 296 ListBuffer<Type> ts = new ListBuffer<>(); 297 for (List<T> l = trees; l.nonEmpty(); l = l.tail) { 298 Type t = classEnter(l.head, env); 299 if (t != null) 300 ts.append(t); 301 } 302 return ts.toList(); 303 } 304 305 @Override 306 public void visitTopLevel(JCCompilationUnit tree) { 307// Assert.checkNonNull(tree.modle, tree.sourcefile.toString()); 308 309 JavaFileObject prev = log.useSource(tree.sourcefile); 310 boolean addEnv = false; 311 boolean isPkgInfo = tree.sourcefile.isNameCompatible("package-info", 312 JavaFileObject.Kind.SOURCE); 313 if (TreeInfo.isModuleInfo(tree)) { 314 JCPackageDecl pd = tree.getPackage(); 315 if (pd != null) { 316 log.error(pd.pos(), Errors.NoPkgInModuleInfoJava); 317 } 318 tree.packge = syms.rootPackage; 319 Env<AttrContext> topEnv = topLevelEnv(tree); 320 classEnter(tree.defs, topEnv); 321 tree.modle.usesProvidesCompleter = modules.getUsesProvidesCompleter(); 322 } else { 323 JCPackageDecl pd = tree.getPackage(); 324 if (pd != null) { 325 tree.packge = pd.packge = syms.enterPackage(tree.modle, TreeInfo.fullName(pd.pid)); 326 if ( pd.annotations.nonEmpty() 327 || pkginfoOpt == PkgInfo.ALWAYS 328 || tree.docComments != null) { 329 if (isPkgInfo) { 330 addEnv = true; 331 } else if (pd.annotations.nonEmpty()) { 332 log.error(pd.annotations.head.pos(), 333 "pkg.annotations.sb.in.package-info.java"); 334 } 335 } 336 } else { 337 tree.packge = tree.modle.unnamedPackage; 338 } 339 340 Map<Name, PackageSymbol> visiblePackages = tree.modle.visiblePackages; 341 Optional<ModuleSymbol> dependencyWithPackage = 342 syms.listPackageModules(tree.packge.fullname) 343 .stream() 344 .filter(m -> m != tree.modle) 345 .filter(cand -> visiblePackages.get(tree.packge.fullname) == syms.getPackage(cand, tree.packge.fullname)) 346 .findAny(); 347 348 if (dependencyWithPackage.isPresent()) { 349 log.error(pd, Errors.PackageInOtherModule(dependencyWithPackage.get())); 350 } 351 352 tree.packge.complete(); // Find all classes in package. 353 354 Env<AttrContext> topEnv = topLevelEnv(tree); 355 Env<AttrContext> packageEnv = isPkgInfo ? topEnv.dup(pd) : null; 356 357 // Save environment of package-info.java file. 358 if (isPkgInfo) { 359 Env<AttrContext> env0 = typeEnvs.get(tree.packge); 360 if (env0 != null) { 361 JCCompilationUnit tree0 = env0.toplevel; 362 if (!fileManager.isSameFile(tree.sourcefile, tree0.sourcefile)) { 363 log.warning(pd != null ? pd.pid.pos() : null, 364 "pkg-info.already.seen", 365 tree.packge); 366 } 367 } 368 typeEnvs.put(tree.packge, packageEnv); 369 370 for (Symbol q = tree.packge; q != null && q.kind == PCK; q = q.owner) 371 q.flags_field |= EXISTS; 372 373 Name name = names.package_info; 374 ClassSymbol c = syms.enterClass(tree.modle, name, tree.packge); 375 c.flatname = names.fromString(tree.packge + "." + name); 376 c.sourcefile = tree.sourcefile; 377 c.completer = Completer.NULL_COMPLETER; 378 c.members_field = WriteableScope.create(c); 379 tree.packge.package_info = c; 380 } 381 classEnter(tree.defs, topEnv); 382 if (addEnv) { 383 todo.append(packageEnv); 384 } 385 } 386 log.useSource(prev); 387 result = null; 388 } 389 390 @Override 391 public void visitClassDef(JCClassDecl tree) { 392 Symbol owner = env.info.scope.owner; 393 WriteableScope enclScope = enterScope(env); 394 ClassSymbol c; 395 if (owner.kind == PCK) { 396 // We are seeing a toplevel class. 397 PackageSymbol packge = (PackageSymbol)owner; 398 for (Symbol q = packge; q != null && q.kind == PCK; q = q.owner) 399 q.flags_field |= EXISTS; 400 c = syms.enterClass(env.toplevel.modle, tree.name, packge); 401 packge.members().enterIfAbsent(c); 402 if ((tree.mods.flags & PUBLIC) != 0 && !classNameMatchesFileName(c, env)) { 403 log.error(tree.pos(), 404 "class.public.should.be.in.file", tree.name); 405 } 406 } else { 407 if (!tree.name.isEmpty() && 408 !chk.checkUniqueClassName(tree.pos(), tree.name, enclScope)) { 409 result = null; 410 return; 411 } 412 if (owner.kind == TYP) { 413 // We are seeing a member class. 414 c = syms.enterClass(env.toplevel.modle, tree.name, (TypeSymbol)owner); 415 if (c.owner != owner) { 416 //anonymous class loaded from a classfile may be recreated from source (see below) 417 //if this class is a member of such an anonymous class, fix the owner: 418 Assert.check(owner.owner.kind != TYP, () -> owner.toString()); 419 Assert.check(c.owner.kind == TYP, () -> c.owner.toString()); 420 ClassSymbol cowner = (ClassSymbol) c.owner; 421 if (cowner.members_field != null) { 422 cowner.members_field.remove(c); 423 } 424 c.owner = owner; 425 } 426 if ((owner.flags_field & INTERFACE) != 0) { 427 tree.mods.flags |= PUBLIC | STATIC; 428 } 429 } else { 430 // We are seeing a local class. 431 c = syms.defineClass(tree.name, owner); 432 c.flatname = chk.localClassName(c); 433 if (!c.name.isEmpty()) 434 chk.checkTransparentClass(tree.pos(), c, env.info.scope); 435 } 436 } 437 tree.sym = c; 438 439 // Enter class into `compiled' table and enclosing scope. 440 if (chk.getCompiled(c) != null) { 441 duplicateClass(tree.pos(), c); 442 result = types.createErrorType(tree.name, (TypeSymbol)owner, Type.noType); 443 tree.sym = (ClassSymbol)result.tsym; 444 return; 445 } 446 chk.putCompiled(c); 447 enclScope.enter(c); 448 449 // Set up an environment for class block and store in `typeEnvs' 450 // table, to be retrieved later in memberEnter and attribution. 451 Env<AttrContext> localEnv = classEnv(tree, env); 452 typeEnvs.put(c, localEnv); 453 454 // Fill out class fields. 455 c.completer = Completer.NULL_COMPLETER; // do not allow the initial completer linger on. 456 c.flags_field = chk.checkFlags(tree.pos(), tree.mods.flags, c, tree); 457 c.sourcefile = env.toplevel.sourcefile; 458 c.members_field = WriteableScope.create(c); 459 c.clearAnnotationMetadata(); 460 461 ClassType ct = (ClassType)c.type; 462 if (owner.kind != PCK && (c.flags_field & STATIC) == 0) { 463 // We are seeing a local or inner class. 464 // Set outer_field of this class to closest enclosing class 465 // which contains this class in a non-static context 466 // (its "enclosing instance class"), provided such a class exists. 467 Symbol owner1 = owner; 468 while (owner1.kind.matches(KindSelector.VAL_MTH) && 469 (owner1.flags_field & STATIC) == 0) { 470 owner1 = owner1.owner; 471 } 472 if (owner1.kind == TYP) { 473 ct.setEnclosingType(owner1.type); 474 } 475 } 476 477 // Enter type parameters. 478 ct.typarams_field = classEnter(tree.typarams, localEnv); 479 ct.allparams_field = null; 480 481 // install further completer for this type. 482 c.completer = typeEnter; 483 484 // Add non-local class to uncompleted, to make sure it will be 485 // completed later. 486 if (!c.isLocal() && uncompleted != null) uncompleted.append(c); 487// System.err.println("entering " + c.fullname + " in " + c.owner);//DEBUG 488 489 // Recursively enter all member classes. 490 classEnter(tree.defs, localEnv); 491 492// Assert.checkNonNull(c.modle, c.sourcefile.toString()); 493 494 result = c.type; 495 } 496 //where 497 /** Does class have the same name as the file it appears in? 498 */ 499 private static boolean classNameMatchesFileName(ClassSymbol c, 500 Env<AttrContext> env) { 501 return env.toplevel.sourcefile.isNameCompatible(c.name.toString(), 502 JavaFileObject.Kind.SOURCE); 503 } 504 505 /** Complain about a duplicate class. */ 506 protected void duplicateClass(DiagnosticPosition pos, ClassSymbol c) { 507 log.error(pos, "duplicate.class", c.fullname); 508 } 509 510 /** Class enter visitor method for type parameters. 511 * Enter a symbol for type parameter in local scope, after checking that it 512 * is unique. 513 */ 514 @Override 515 public void visitTypeParameter(JCTypeParameter tree) { 516 TypeVar a = (tree.type != null) 517 ? (TypeVar)tree.type 518 : new TypeVar(tree.name, env.info.scope.owner, syms.botType); 519 tree.type = a; 520 if (chk.checkUnique(tree.pos(), a.tsym, env.info.scope)) { 521 env.info.scope.enter(a.tsym); 522 } 523 result = a; 524 } 525 526 @Override 527 public void visitModuleDef(JCModuleDecl tree) { 528 Env<AttrContext> moduleEnv = moduleEnv(tree, env); 529 typeEnvs.put(tree.sym, moduleEnv); 530 if (modules.isInModuleGraph(tree.sym)) { 531 todo.append(moduleEnv); 532 } 533 } 534 535 /** Default class enter visitor method: do nothing. 536 */ 537 @Override 538 public void visitTree(JCTree tree) { 539 result = null; 540 } 541 542 /** Main method: enter all classes in a list of toplevel trees. 543 * @param trees The list of trees to be processed. 544 */ 545 public void main(List<JCCompilationUnit> trees) { 546 complete(trees, null); 547 } 548 549 /** Main method: enter classes from the list of toplevel trees, possibly 550 * skipping TypeEnter for all but 'c' by placing them on the uncompleted 551 * list. 552 * @param trees The list of trees to be processed. 553 * @param c The class symbol to be processed or null to process all. 554 */ 555 public void complete(List<JCCompilationUnit> trees, ClassSymbol c) { 556 annotate.blockAnnotations(); 557 ListBuffer<ClassSymbol> prevUncompleted = uncompleted; 558 if (typeEnter.completionEnabled) uncompleted = new ListBuffer<>(); 559 560 try { 561 // enter all classes, and construct uncompleted list 562 classEnter(trees, null); 563 564 // complete all uncompleted classes in memberEnter 565 if (typeEnter.completionEnabled) { 566 while (uncompleted.nonEmpty()) { 567 ClassSymbol clazz = uncompleted.next(); 568 if (c == null || c == clazz || prevUncompleted == null) 569 clazz.complete(); 570 else 571 // defer 572 prevUncompleted.append(clazz); 573 } 574 575 if (!modules.modulesInitialized()) { 576 for (JCCompilationUnit cut : trees) { 577 if (cut.getModuleDecl() != null) { 578 unfinishedModules.append(cut); 579 } else { 580 typeEnter.ensureImportsChecked(List.of(cut)); 581 } 582 } 583 } else { 584 typeEnter.ensureImportsChecked(unfinishedModules.toList()); 585 unfinishedModules.clear(); 586 typeEnter.ensureImportsChecked(trees); 587 } 588 } 589 } finally { 590 uncompleted = prevUncompleted; 591 annotate.unblockAnnotations(); 592 } 593 } 594 595 public void newRound() { 596 typeEnvs.clear(); 597 } 598} 599