1 /*
   2  * Copyright (c) 2003, 2025, 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 
  26 package com.sun.tools.javac.comp;
  27 
  28 import com.sun.tools.javac.code.*;
  29 import com.sun.tools.javac.code.Attribute.Compound;
  30 import com.sun.tools.javac.code.Attribute.TypeCompound;
  31 import com.sun.tools.javac.code.Kinds.KindSelector;
  32 import com.sun.tools.javac.code.Scope.WriteableScope;
  33 import com.sun.tools.javac.code.Source.Feature;
  34 import com.sun.tools.javac.code.Symbol.*;
  35 import com.sun.tools.javac.code.TypeMetadata.Annotations;
  36 import com.sun.tools.javac.comp.Check.CheckContext;
  37 import com.sun.tools.javac.resources.CompilerProperties.Errors;
  38 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
  39 import com.sun.tools.javac.tree.JCTree;
  40 import com.sun.tools.javac.tree.JCTree.*;
  41 import com.sun.tools.javac.tree.TreeInfo;
  42 import com.sun.tools.javac.tree.TreeMaker;
  43 import com.sun.tools.javac.tree.TreeScanner;
  44 import com.sun.tools.javac.util.*;
  45 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
  46 import com.sun.tools.javac.util.List;
  47 
  48 import javax.tools.JavaFileObject;
  49 
  50 import java.util.*;
  51 
  52 import static com.sun.tools.javac.code.Flags.SYNTHETIC;
  53 import static com.sun.tools.javac.code.Kinds.Kind.MDL;
  54 import static com.sun.tools.javac.code.Kinds.Kind.MTH;
  55 import static com.sun.tools.javac.code.Kinds.Kind.PCK;
  56 import static com.sun.tools.javac.code.Kinds.Kind.TYP;
  57 import static com.sun.tools.javac.code.Kinds.Kind.VAR;
  58 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
  59 import static com.sun.tools.javac.code.TypeTag.ARRAY;
  60 import static com.sun.tools.javac.code.TypeTag.CLASS;
  61 import static com.sun.tools.javac.tree.JCTree.Tag.ANNOTATION;
  62 import static com.sun.tools.javac.tree.JCTree.Tag.ASSIGN;
  63 import static com.sun.tools.javac.tree.JCTree.Tag.IDENT;
  64 import static com.sun.tools.javac.tree.JCTree.Tag.NEWARRAY;
  65 
  66 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
  67 
  68 
  69 /** Enter annotations onto symbols and types (and trees).
  70  *
  71  *  This is also a pseudo stage in the compiler taking care of scheduling when annotations are
  72  *  entered.
  73  *
  74  *  <p><b>This is NOT part of any supported API.
  75  *  If you write code that depends on this, you do so at your own risk.
  76  *  This code and its internal interfaces are subject to change or
  77  *  deletion without notice.</b>
  78  */
  79 public class Annotate {
  80     protected static final Context.Key<Annotate> annotateKey = new Context.Key<>();
  81 
  82     public static Annotate instance(Context context) {
  83         Annotate instance = context.get(annotateKey);
  84         if (instance == null)
  85             instance = new Annotate(context);
  86         return instance;
  87     }
  88 
  89     private final Attr attr;
  90     private final Check chk;
  91     private final ConstFold cfolder;
  92     private final Enter enter;
  93     private final Log log;
  94     private final Names names;
  95     private final Resolve resolve;
  96     private final TreeMaker make;
  97     private final Symtab syms;
  98     private final TypeEnvs typeEnvs;
  99     private final Types types;
 100     private final Preview preview;
 101 
 102     private final Attribute theUnfinishedDefaultValue;
 103     private final String sourceName;
 104 
 105     @SuppressWarnings("this-escape")
 106     protected Annotate(Context context) {
 107         context.put(annotateKey, this);
 108 
 109         attr = Attr.instance(context);
 110         chk = Check.instance(context);
 111         cfolder = ConstFold.instance(context);
 112         enter = Enter.instance(context);
 113         log = Log.instance(context);
 114         make = TreeMaker.instance(context);
 115         names = Names.instance(context);
 116         resolve = Resolve.instance(context);
 117         syms = Symtab.instance(context);
 118         typeEnvs = TypeEnvs.instance(context);
 119         types = Types.instance(context);
 120         preview = Preview.instance(context);
 121 
 122         theUnfinishedDefaultValue =  new Attribute.Error(syms.errType);
 123 
 124         Source source = Source.instance(context);
 125         sourceName = source.name;
 126 
 127         blockCount = 1;
 128     }
 129 
 130     /** Semaphore to delay annotation processing */
 131     private int blockCount = 0;
 132 
 133     /** Called when annotations processing needs to be postponed. */
 134     public void blockAnnotations() {
 135         blockCount++;
 136     }
 137 
 138     /** Called when annotation processing can be resumed. */
 139     public void unblockAnnotations() {
 140         blockCount--;
 141         if (blockCount == 0)
 142             flush();
 143     }
 144 
 145     /** Variant which allows for a delayed flush of annotations.
 146      * Needed by ClassReader */
 147     public void unblockAnnotationsNoFlush() {
 148         blockCount--;
 149     }
 150 
 151     /** are we blocking annotation processing? */
 152     public boolean annotationsBlocked() {return blockCount > 0; }
 153 
 154     public void enterDone() {
 155         unblockAnnotations();
 156     }
 157 
 158     public List<TypeCompound> fromAnnotations(List<JCAnnotation> annotations) {
 159         if (annotations.isEmpty()) {
 160             return List.nil();
 161         }
 162 
 163         ListBuffer<TypeCompound> buf = new ListBuffer<>();
 164         for (JCAnnotation anno : annotations) {
 165             Assert.checkNonNull(anno.attribute);
 166             buf.append((TypeCompound) anno.attribute);
 167         }
 168         return buf.toList();
 169     }
 170 
 171     /** Annotate (used for everything else) */
 172     public void normal(Runnable r) {
 173         q.append(r);
 174     }
 175 
 176     /** Validate, triggers after 'normal' */
 177     public void validate(Runnable a) {
 178         validateQ.append(a);
 179     }
 180 
 181     /** Flush all annotation queues */
 182     public void flush() {
 183         if (annotationsBlocked()) return;
 184         if (isFlushing()) return;
 185 
 186         startFlushing();
 187         try {
 188             while (q.nonEmpty() ||
 189                    typesQ.nonEmpty() ||
 190                    afterTypesQ.nonEmpty() ||
 191                    validateQ.nonEmpty()) {
 192                 while (q.nonEmpty()) {
 193                     q.next().run();
 194                 }
 195                 while (typesQ.nonEmpty()) {
 196                     typesQ.next().run();
 197                 }
 198                 while (afterTypesQ.nonEmpty()) {
 199                     afterTypesQ.next().run();
 200                 }
 201                 while (validateQ.nonEmpty()) {
 202                     validateQ.next().run();
 203                 }
 204             }
 205         } finally {
 206             doneFlushing();
 207         }
 208     }
 209 
 210     private ListBuffer<Runnable> q = new ListBuffer<>();
 211     private ListBuffer<Runnable> validateQ = new ListBuffer<>();
 212 
 213     private int flushCount = 0;
 214     private boolean isFlushing() { return flushCount > 0; }
 215     private void startFlushing() { flushCount++; }
 216     private void doneFlushing() { flushCount--; }
 217 
 218     ListBuffer<Runnable> typesQ = new ListBuffer<>();
 219     ListBuffer<Runnable> afterTypesQ = new ListBuffer<>();
 220 
 221 
 222     public void typeAnnotation(Runnable a) {
 223         typesQ.append(a);
 224     }
 225 
 226     public void afterTypes(Runnable a) {
 227         afterTypesQ.append(a);
 228     }
 229 
 230     /**
 231      * Queue annotations for later attribution and entering. This is probably the method you are looking for.
 232      *
 233      * @param annotations the list of JCAnnotations to attribute and enter
 234      * @param localEnv    the enclosing env
 235      * @param s           the Symbol on which to enter the annotations
 236      */
 237     public void annotateLater(List<JCAnnotation> annotations, Env<AttrContext> localEnv, Symbol s)
 238     {
 239         if (annotations.isEmpty()) {
 240             return;
 241         }
 242 
 243         s.resetAnnotations(); // mark Annotations as incomplete for now
 244 
 245         normal(() -> {
 246             // Packages are unusual, in that they are the only type of declaration that can legally appear
 247             // more than once in a compilation, and in all cases refer to the same underlying symbol.
 248             // This means they are the only kind of declaration that syntactically may have multiple sets
 249             // of annotations, each on a different package declaration, even though that is ultimately
 250             // forbidden by JLS 8 section 7.4.
 251             // The corollary here is that all of the annotations on a package symbol may have already
 252             // been handled, meaning that the set of annotations pending completion is now empty.
 253             Assert.check(s.kind == PCK || s.annotationsPendingCompletion());
 254             JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);
 255             try {
 256                 if (s.hasAnnotations() && annotations.nonEmpty())
 257                     log.error(annotations.head.pos, Errors.AlreadyAnnotated(Kinds.kindName(s), s));
 258 
 259                 Assert.checkNonNull(s, "Symbol argument to actualEnterAnnotations is null");
 260 
 261                 // false is passed as fifth parameter since annotateLater is
 262                 // never called for a type parameter
 263                 annotateNow(s, annotations, localEnv, false, false);
 264             } finally {
 265                 log.useSource(prev);
 266             }
 267         });
 268 
 269         validate(() -> { //validate annotations
 270             JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);
 271             try {
 272                 chk.validateAnnotations(annotations, TreeInfo.declarationFor(s, localEnv.tree), s);
 273             } finally {
 274                 log.useSource(prev);
 275             }
 276         });
 277     }
 278 
 279 
 280     /** Queue processing of an attribute default value. */
 281     public void annotateDefaultValueLater(JCExpression defaultValue, Env<AttrContext> localEnv, MethodSymbol m)
 282     {
 283         normal(() -> {
 284             JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);
 285             try {
 286                 enterDefaultValue(defaultValue, localEnv, m);
 287             } finally {
 288                 log.useSource(prev);
 289             }
 290         });
 291 
 292         validate(() -> { //validate annotations
 293             JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);
 294             try {
 295                 // if default value is an annotation, check it is a well-formed
 296                 // annotation value (e.g. no duplicate values, no missing values, etc.)
 297                 chk.validateAnnotationTree(defaultValue);
 298             } finally {
 299                 log.useSource(prev);
 300             }
 301         });
 302     }
 303 
 304     /** Enter a default value for an annotation element. */
 305     private void enterDefaultValue(JCExpression defaultValue,
 306             Env<AttrContext> localEnv, MethodSymbol m) {
 307         m.defaultValue = attributeAnnotationValue(m.type.getReturnType(), defaultValue, localEnv);
 308     }
 309 
 310     /**
 311      * Gather up annotations into a map from type symbols to lists of Compound attributes,
 312      * then continue on with repeating annotations processing.
 313      */
 314     private <T extends Attribute.Compound> void annotateNow(Symbol toAnnotate,
 315             List<JCAnnotation> withAnnotations, Env<AttrContext> env, boolean typeAnnotations,
 316             boolean isTypeParam)
 317     {
 318         Map<TypeSymbol, ListBuffer<T>> annotated = new LinkedHashMap<>();
 319         Map<T, DiagnosticPosition> pos = new HashMap<>();
 320 
 321         for (List<JCAnnotation> al = withAnnotations; !al.isEmpty(); al = al.tail) {
 322             JCAnnotation a = al.head;
 323 
 324             T c;
 325             if (typeAnnotations) {
 326                 @SuppressWarnings("unchecked")
 327                 T tmp = (T)attributeTypeAnnotation(a, syms.annotationType, env);
 328                 c = tmp;
 329             } else {
 330                 @SuppressWarnings("unchecked")
 331                 T tmp = (T)attributeAnnotation(a, syms.annotationType, env);
 332                 c = tmp;
 333             }
 334 
 335             Assert.checkNonNull(c, "Failed to create annotation");
 336 
 337             if (env.info.isAnonymousNewClass) {
 338                 // Annotations on anonymous class instantiations should be attributed,
 339                 // but not attached to the enclosing element. They will be visited
 340                 // separately and attached to the synthetic class declaration.
 341                 continue;
 342             }
 343 
 344             if (a.type.isErroneous() || a.type.tsym.isAnnotationType()) {
 345                 if (annotated.containsKey(a.type.tsym)) {
 346                     ListBuffer<T> l = annotated.get(a.type.tsym);
 347                     l = l.append(c);
 348                     annotated.put(a.type.tsym, l);
 349                     pos.put(c, a.pos());
 350                 } else {
 351                     annotated.put(a.type.tsym, ListBuffer.of(c));
 352                     pos.put(c, a.pos());
 353                 }
 354             }
 355 
 356             // Note: @Deprecated has no effect on local variables and parameters
 357             if (!c.type.isErroneous()
 358                     && (toAnnotate.kind == MDL || toAnnotate.owner.kind != MTH)
 359                     && types.isSameType(c.type, syms.deprecatedType)) {
 360                 toAnnotate.flags_field |= (Flags.DEPRECATED | Flags.DEPRECATED_ANNOTATION);
 361                 if (isAttributeTrue(c.member(names.forRemoval))) {
 362                     toAnnotate.flags_field |= Flags.DEPRECATED_REMOVAL;
 363                 }
 364             }
 365 
 366             if (!c.type.isErroneous()
 367                     && types.isSameType(c.type, syms.previewFeatureType)) {
 368                 toAnnotate.flags_field |= Flags.PREVIEW_API;
 369                 if (isAttributeTrue(c.member(names.reflective))) {
 370                     toAnnotate.flags_field |= Flags.PREVIEW_REFLECTIVE;
 371                 }
 372             }
 373 
 374             if (!c.type.isErroneous()
 375                     && toAnnotate.kind == TYP
 376                     && types.isSameType(c.type, syms.valueBasedType)) {
 377                 toAnnotate.flags_field |= Flags.VALUE_BASED;
 378             }
 379 
 380             if (!c.type.isErroneous()
 381                     && toAnnotate.kind == TYP
 382                     && types.isSameType(c.type, syms.migratedValueClassType)) {
 383                 toAnnotate.flags_field |= Flags.MIGRATED_VALUE_CLASS;
 384             }
 385 
 386             if (!c.type.isErroneous()
 387                     && toAnnotate.kind == VAR
 388                     && toAnnotate.owner.kind == TYP
 389                     && types.isSameType(c.type, syms.strictType)) {
 390                 preview.checkSourceLevel(pos.get(c), Feature.VALUE_CLASSES);
 391                 toAnnotate.flags_field |= Flags.STRICT;
 392                 // temporary hack to indicate that a class has at least one strict field
 393                 toAnnotate.owner.flags_field |= Flags.HAS_STRICT;
 394             }
 395 
 396             if (!c.type.isErroneous()
 397                     && types.isSameType(c.type, syms.restrictedType)) {
 398                 toAnnotate.flags_field |= Flags.RESTRICTED;
 399             }
 400 
 401             if (!c.type.isErroneous()
 402                     && toAnnotate.kind == VAR
 403                     && types.isSameType(c.type, syms.requiresIdentityType)) {
 404                 toAnnotate.flags_field |= Flags.REQUIRES_IDENTITY;
 405             }
 406         }
 407 
 408         List<T> buf = List.nil();
 409         for (ListBuffer<T> lb : annotated.values()) {
 410             if (lb.size() == 1) {
 411                 buf = buf.prepend(lb.first());
 412             } else {
 413                 AnnotationContext<T> ctx = new AnnotationContext<>(env, annotated, pos, typeAnnotations);
 414                 T res = makeContainerAnnotation(lb.toList(), ctx, toAnnotate, isTypeParam);
 415                 if (res != null)
 416                     buf = buf.prepend(res);
 417             }
 418         }
 419 
 420         if (typeAnnotations) {
 421             @SuppressWarnings("unchecked")
 422             List<TypeCompound> attrs = (List<TypeCompound>)buf.reverse();
 423             toAnnotate.appendUniqueTypeAttributes(attrs);
 424         } else {
 425             @SuppressWarnings("unchecked")
 426             List<Attribute.Compound> attrs =  (List<Attribute.Compound>)buf.reverse();
 427             toAnnotate.resetAnnotations();
 428             toAnnotate.setDeclarationAttributes(attrs);
 429         }
 430     }
 431     //where:
 432         private boolean isAttributeTrue(Attribute attr) {
 433             return (attr instanceof Attribute.Constant constant)
 434                     && constant.type == syms.booleanType
 435                     && ((Integer) constant.value) != 0;
 436         }
 437 
 438     /**
 439      * Attribute and store a semantic representation of the annotation tree {@code tree} into the
 440      * tree.attribute field.
 441      *
 442      * @param tree the tree representing an annotation
 443      * @param expectedAnnotationType the expected (super)type of the annotation
 444      * @param env the current env in where the annotation instance is found
 445      */
 446     public Attribute.Compound attributeAnnotation(JCAnnotation tree, Type expectedAnnotationType,
 447                                                   Env<AttrContext> env)
 448     {
 449         // The attribute might have been entered if it is Target or Repeatable
 450         // Because TreeCopier does not copy type, redo this if type is null
 451         if (tree.attribute != null && tree.type != null)
 452             return tree.attribute;
 453 
 454         List<Pair<MethodSymbol, Attribute>> elems = attributeAnnotationValues(tree, expectedAnnotationType, env);
 455         Attribute.Compound ac = new Attribute.Compound(tree.type, elems);
 456 
 457         return tree.attribute = ac;
 458     }
 459 
 460     /** Attribute and store a semantic representation of the type annotation tree {@code tree} into
 461      * the tree.attribute field.
 462      *
 463      * @param a the tree representing an annotation
 464      * @param expectedAnnotationType the expected (super)type of the annotation
 465      * @param env the current env in where the annotation instance is found
 466      */
 467     public Attribute.TypeCompound attributeTypeAnnotation(JCAnnotation a, Type expectedAnnotationType,
 468                                                           Env<AttrContext> env)
 469     {
 470         // The attribute might have been entered if it is Target or Repeatable
 471         // Because TreeCopier does not copy type, redo this if type is null
 472         if (a.attribute == null || a.type == null || !(a.attribute instanceof Attribute.TypeCompound typeCompound)) {
 473             // Create a new TypeCompound
 474             List<Pair<MethodSymbol,Attribute>> elems =
 475                     attributeAnnotationValues(a, expectedAnnotationType, env);
 476 
 477             Attribute.TypeCompound tc =
 478                     new Attribute.TypeCompound(a.type, elems, TypeAnnotationPosition.unknown);
 479             a.attribute = tc;
 480             return tc;
 481         } else {
 482             // Use an existing TypeCompound
 483             return typeCompound;
 484         }
 485     }
 486 
 487     /**
 488      *  Attribute annotation elements creating a list of pairs of the Symbol representing that
 489      *  element and the value of that element as an Attribute. */
 490     private List<Pair<MethodSymbol, Attribute>> attributeAnnotationValues(JCAnnotation a,
 491             Type expected, Env<AttrContext> env)
 492     {
 493         // The annotation might have had its type attributed (but not
 494         // checked) by attr.attribAnnotationTypes during MemberEnter,
 495         // in which case we do not need to do it again.
 496         Type at = (a.annotationType.type != null ?
 497                 a.annotationType.type : attr.attribType(a.annotationType, env));
 498         a.type = chk.checkType(a.annotationType.pos(), at, expected);
 499 
 500         boolean isError = a.type.isErroneous();
 501         if (!a.type.tsym.isAnnotationType() && !isError) {
 502             log.error(a.annotationType.pos(), Errors.NotAnnotationType(a.type));
 503             isError = true;
 504         }
 505 
 506         // List of name=value pairs (or implicit "value=" if size 1)
 507         List<JCExpression> args = a.args;
 508 
 509         boolean elidedValue = false;
 510         // special case: elided "value=" assumed
 511         if (args.length() == 1 && !args.head.hasTag(ASSIGN)) {
 512             args.head = make.at(args.head.pos).
 513                     Assign(make.Ident(names.value), args.head);
 514             elidedValue = true;
 515         }
 516 
 517         ListBuffer<Pair<MethodSymbol,Attribute>> buf = new ListBuffer<>();
 518         for (List<JCExpression> tl = args; tl.nonEmpty(); tl = tl.tail) {
 519             Pair<MethodSymbol, Attribute> p = attributeAnnotationNameValuePair(tl.head, a.type, isError, env, elidedValue);
 520             if (p != null && !p.fst.type.isErroneous())
 521                 buf.append(p);
 522         }
 523         return buf.toList();
 524     }
 525 
 526     // where
 527     private Pair<MethodSymbol, Attribute> attributeAnnotationNameValuePair(JCExpression nameValuePair,
 528             Type thisAnnotationType, boolean badAnnotation, Env<AttrContext> env, boolean elidedValue)
 529     {
 530         if (!nameValuePair.hasTag(ASSIGN)) {
 531             log.error(nameValuePair.pos(), Errors.AnnotationValueMustBeNameValue);
 532             attributeAnnotationValue(nameValuePair.type = syms.errType, nameValuePair, env);
 533             return null;
 534         }
 535         JCAssign assign = (JCAssign)nameValuePair;
 536         if (!assign.lhs.hasTag(IDENT)) {
 537             log.error(nameValuePair.pos(), Errors.AnnotationValueMustBeNameValue);
 538             attributeAnnotationValue(nameValuePair.type = syms.errType, nameValuePair, env);
 539             return null;
 540         }
 541 
 542         // Resolve element to MethodSym
 543         JCIdent left = (JCIdent)assign.lhs;
 544         Symbol method = resolve.resolveQualifiedMethod(elidedValue ? assign.rhs.pos() : left.pos(),
 545                 env, thisAnnotationType,
 546                 left.name, List.nil(), null);
 547         left.sym = method;
 548         left.type = method.type;
 549         chk.checkDeprecated(left, env.info.scope.owner, method);
 550         if (method.owner != thisAnnotationType.tsym && !badAnnotation)
 551             log.error(left.pos(), Errors.NoAnnotationMember(left.name, thisAnnotationType));
 552         Type resultType = method.type.getReturnType();
 553 
 554         // Compute value part
 555         Attribute value = attributeAnnotationValue(resultType, assign.rhs, env);
 556         nameValuePair.type = resultType;
 557 
 558         return method.type.isErroneous() ? null : new Pair<>((MethodSymbol)method, value);
 559 
 560     }
 561 
 562     /** Attribute an annotation element value */
 563     private Attribute attributeAnnotationValue(Type expectedElementType, JCExpression tree,
 564             Env<AttrContext> env)
 565     {
 566         //first, try completing the symbol for the annotation value - if a completion
 567         //error is thrown, we should recover gracefully, and display an
 568         //ordinary resolution diagnostic.
 569         try {
 570             expectedElementType.tsym.complete();
 571         } catch(CompletionFailure e) {
 572             log.error(tree.pos(), Errors.CantResolve(Kinds.kindName(e.sym), e.sym.getQualifiedName(), null, null));
 573             expectedElementType = syms.errType;
 574         }
 575 
 576         if (expectedElementType.hasTag(ARRAY)) {
 577             return getAnnotationArrayValue(expectedElementType, tree, env);
 578         }
 579 
 580         //error recovery
 581         if (tree.hasTag(NEWARRAY)) {
 582             if (!expectedElementType.isErroneous())
 583                 log.error(tree.pos(), Errors.AnnotationValueNotAllowableType);
 584             JCNewArray na = (JCNewArray)tree;
 585             if (na.elemtype != null) {
 586                 log.error(na.elemtype.pos(), Errors.NewNotAllowedInAnnotation);
 587             }
 588             for (List<JCExpression> l = na.elems; l.nonEmpty(); l=l.tail) {
 589                 attributeAnnotationValue(syms.errType,
 590                         l.head,
 591                         env);
 592             }
 593             return new Attribute.Error(syms.errType);
 594         }
 595 
 596         if (expectedElementType.tsym.isAnnotationType()) {
 597             if (tree.hasTag(ANNOTATION)) {
 598                 return attributeAnnotation((JCAnnotation)tree, expectedElementType, env);
 599             } else {
 600                 log.error(tree.pos(), Errors.AnnotationValueMustBeAnnotation);
 601                 expectedElementType = syms.errType;
 602             }
 603         }
 604 
 605         //error recovery
 606         if (tree.hasTag(ANNOTATION)) {
 607             if (!expectedElementType.isErroneous())
 608                 log.error(tree.pos(), Errors.AnnotationNotValidForType(expectedElementType));
 609             attributeAnnotation((JCAnnotation)tree, syms.errType, env);
 610             return new Attribute.Error(((JCAnnotation)tree).annotationType.type);
 611         }
 612 
 613         MemberEnter.InitTreeVisitor initTreeVisitor = new MemberEnter.InitTreeVisitor() {
 614             // the methods below are added to allow class literals on top of constant expressions
 615             @Override
 616             public void visitTypeIdent(JCPrimitiveTypeTree that) {}
 617 
 618             @Override
 619             public void visitTypeArray(JCArrayTypeTree that) {}
 620         };
 621         tree.accept(initTreeVisitor);
 622         if (!initTreeVisitor.result) {
 623             log.error(tree.pos(), Errors.ExpressionNotAllowableAsAnnotationValue);
 624             return new Attribute.Error(syms.errType);
 625         }
 626 
 627         if (expectedElementType.isPrimitive() ||
 628                 (types.isSameType(expectedElementType, syms.stringType) && !expectedElementType.hasTag(TypeTag.ERROR))) {
 629             return getAnnotationPrimitiveValue(expectedElementType, tree, env);
 630         }
 631 
 632         if (expectedElementType.tsym == syms.classType.tsym) {
 633             return getAnnotationClassValue(expectedElementType, tree, env);
 634         }
 635 
 636         if (expectedElementType.hasTag(CLASS) &&
 637                 (expectedElementType.tsym.flags() & Flags.ENUM) != 0) {
 638             return getAnnotationEnumValue(expectedElementType, tree, env);
 639         }
 640 
 641         //error recovery:
 642         if (!expectedElementType.isErroneous())
 643             log.error(tree.pos(), Errors.AnnotationValueNotAllowableType);
 644         return new Attribute.Error(attr.attribExpr(tree, env, expectedElementType));
 645     }
 646 
 647     private Attribute getAnnotationEnumValue(Type expectedElementType, JCExpression tree, Env<AttrContext> env) {
 648         Type result = attr.attribTree(tree, env, annotationValueInfo(expectedElementType));
 649         Symbol sym = TreeInfo.symbol(tree);
 650         if (sym == null ||
 651                 TreeInfo.nonstaticSelect(tree) ||
 652                 sym.kind != VAR ||
 653                 (sym.flags() & Flags.ENUM) == 0) {
 654             log.error(tree.pos(), Errors.EnumAnnotationMustBeEnumConstant);
 655             return new Attribute.Error(result.getOriginalType());
 656         }
 657         VarSymbol enumerator = (VarSymbol) sym;
 658         return new Attribute.Enum(expectedElementType, enumerator);
 659     }
 660 
 661     private Attribute getAnnotationClassValue(Type expectedElementType, JCExpression tree, Env<AttrContext> env) {
 662         Type result = attr.attribTree(tree, env, annotationValueInfo(expectedElementType));
 663         if (result.isErroneous()) {
 664             // Does it look like an unresolved class literal?
 665             if (TreeInfo.name(tree) == names._class &&
 666                     ((JCFieldAccess) tree).selected.type.isErroneous()) {
 667                 Name n = (((JCFieldAccess) tree).selected).type.tsym.flatName();
 668                 return new Attribute.UnresolvedClass(expectedElementType,
 669                         types.createErrorType(n,
 670                                 syms.unknownSymbol, syms.classType));
 671             } else {
 672                 return new Attribute.Error(result.getOriginalType());
 673             }
 674         }
 675 
 676         // Class literals look like field accesses of a field named class
 677         // at the tree level
 678         if (TreeInfo.name(tree) != names._class) {
 679             log.error(tree.pos(), Errors.AnnotationValueMustBeClassLiteral);
 680             return new Attribute.Error(syms.errType);
 681         }
 682 
 683         return new Attribute.Class(types,
 684                 (((JCFieldAccess) tree).selected).type);
 685     }
 686 
 687     private Attribute getAnnotationPrimitiveValue(Type expectedElementType, JCExpression tree, Env<AttrContext> env) {
 688         Type result = attr.attribTree(tree, env, annotationValueInfo(expectedElementType));
 689         if (result.isErroneous())
 690             return new Attribute.Error(result.getOriginalType());
 691         if (result.constValue() == null) {
 692             log.error(tree.pos(), Errors.AttributeValueMustBeConstant);
 693             return new Attribute.Error(expectedElementType);
 694         }
 695 
 696         // Scan the annotation element value and then attribute nested annotations if present
 697         if (tree.type != null && tree.type.tsym != null) {
 698             queueScanTreeAndTypeAnnotate(tree, env, tree.type.tsym);
 699         }
 700 
 701         result = cfolder.coerce(result, expectedElementType);
 702         return new Attribute.Constant(expectedElementType, result.constValue());
 703     }
 704 
 705     private Attr.ResultInfo annotationValueInfo(Type pt) {
 706         return attr.unknownExprInfo.dup(pt, new AnnotationValueContext(attr.unknownExprInfo.checkContext));
 707     }
 708 
 709     class AnnotationValueContext extends Check.NestedCheckContext {
 710         AnnotationValueContext(CheckContext enclosingContext) {
 711             super(enclosingContext);
 712         }
 713 
 714         @Override
 715         public boolean compatible(Type found, Type req, Warner warn) {
 716             //handle non-final implicitly-typed vars (will be rejected later on)
 717             return found.hasTag(TypeTag.NONE) || super.compatible(found, req, warn);
 718         }
 719     }
 720 
 721     private Attribute getAnnotationArrayValue(Type expectedElementType, JCExpression tree, Env<AttrContext> env) {
 722         // Special case, implicit array
 723         if (!tree.hasTag(NEWARRAY)) {
 724             tree = make.at(tree.pos).
 725                     NewArray(null, List.nil(), List.of(tree));
 726         }
 727 
 728         JCNewArray na = (JCNewArray)tree;
 729         List<JCExpression> elems = na.elems;
 730         if (na.elemtype != null) {
 731             log.error(na.elemtype.pos(), Errors.NewNotAllowedInAnnotation);
 732             if (elems == null) {
 733                 elems = List.nil();
 734             }
 735         }
 736         ListBuffer<Attribute> buf = new ListBuffer<>();
 737         for (List<JCExpression> l = elems; l.nonEmpty(); l = l.tail) {
 738             buf.append(attributeAnnotationValue(types.elemtype(expectedElementType),
 739                     l.head,
 740                     env));
 741         }
 742         na.type = expectedElementType;
 743         return new Attribute.
 744                 Array(expectedElementType, buf.toArray(new Attribute[buf.length()]));
 745     }
 746 
 747     /* *********************************
 748      * Support for repeating annotations
 749      ***********************************/
 750 
 751     /**
 752      * This context contains all the information needed to synthesize new
 753      * annotations trees for repeating annotations.
 754      */
 755     private class AnnotationContext<T extends Attribute.Compound> {
 756         public final Env<AttrContext> env;
 757         public final Map<Symbol.TypeSymbol, ListBuffer<T>> annotated;
 758         public final Map<T, JCDiagnostic.DiagnosticPosition> pos;
 759         public final boolean isTypeCompound;
 760 
 761         public AnnotationContext(Env<AttrContext> env,
 762                                  Map<Symbol.TypeSymbol, ListBuffer<T>> annotated,
 763                                  Map<T, JCDiagnostic.DiagnosticPosition> pos,
 764                                  boolean isTypeCompound) {
 765             Assert.checkNonNull(env);
 766             Assert.checkNonNull(annotated);
 767             Assert.checkNonNull(pos);
 768 
 769             this.env = env;
 770             this.annotated = annotated;
 771             this.pos = pos;
 772             this.isTypeCompound = isTypeCompound;
 773         }
 774     }
 775 
 776     /* Process repeated annotations. This method returns the
 777      * synthesized container annotation or null IFF all repeating
 778      * annotation are invalid.  This method reports errors/warnings.
 779      */
 780     private <T extends Attribute.Compound> T processRepeatedAnnotations(List<T> annotations,
 781             AnnotationContext<T> ctx, Symbol on, boolean isTypeParam)
 782     {
 783         T firstOccurrence = annotations.head;
 784         List<Attribute> repeated = List.nil();
 785         Type origAnnoType = null;
 786         Type arrayOfOrigAnnoType = null;
 787         Type targetContainerType = null;
 788         MethodSymbol containerValueSymbol = null;
 789 
 790         Assert.check(!annotations.isEmpty() && !annotations.tail.isEmpty()); // i.e. size() > 1
 791 
 792         int count = 0;
 793         for (List<T> al = annotations; !al.isEmpty(); al = al.tail) {
 794             count++;
 795 
 796             // There must be more than a single anno in the annotation list
 797             Assert.check(count > 1 || !al.tail.isEmpty());
 798 
 799             T currentAnno = al.head;
 800 
 801             origAnnoType = currentAnno.type;
 802             if (arrayOfOrigAnnoType == null) {
 803                 arrayOfOrigAnnoType = types.makeArrayType(origAnnoType);
 804             }
 805 
 806             // Only report errors if this isn't the first occurrence I.E. count > 1
 807             boolean reportError = count > 1;
 808             Type currentContainerType = getContainingType(currentAnno, ctx.pos.get(currentAnno), reportError);
 809             if (currentContainerType == null) {
 810                 continue;
 811             }
 812             // Assert that the target Container is == for all repeated
 813             // annos of the same annotation type, the types should
 814             // come from the same Symbol, i.e. be '=='
 815             Assert.check(targetContainerType == null || currentContainerType == targetContainerType);
 816             targetContainerType = currentContainerType;
 817 
 818             containerValueSymbol = validateContainer(targetContainerType, origAnnoType, ctx.pos.get(currentAnno));
 819 
 820             if (containerValueSymbol == null) { // Check of CA type failed
 821                 // errors are already reported
 822                 continue;
 823             }
 824 
 825             repeated = repeated.prepend(currentAnno);
 826         }
 827 
 828         if (!repeated.isEmpty() && targetContainerType == null) {
 829             log.error(ctx.pos.get(annotations.head), Errors.DuplicateAnnotationInvalidRepeated(origAnnoType));
 830             return null;
 831         }
 832 
 833         if (!repeated.isEmpty()) {
 834             repeated = repeated.reverse();
 835             DiagnosticPosition pos = ctx.pos.get(firstOccurrence);
 836             TreeMaker m = make.at(pos);
 837             Pair<MethodSymbol, Attribute> p =
 838                     new Pair<MethodSymbol, Attribute>(containerValueSymbol,
 839                             new Attribute.Array(arrayOfOrigAnnoType, repeated));
 840             if (ctx.isTypeCompound) {
 841                 /* TODO: the following code would be cleaner:
 842                 Attribute.TypeCompound at = new Attribute.TypeCompound(targetContainerType, List.of(p),
 843                         ((Attribute.TypeCompound)annotations.head).position);
 844                 JCTypeAnnotation annoTree = m.TypeAnnotation(at);
 845                 at = attributeTypeAnnotation(annoTree, targetContainerType, ctx.env);
 846                 */
 847                 // However, we directly construct the TypeCompound to keep the
 848                 // direct relation to the contained TypeCompounds.
 849                 Attribute.TypeCompound at = new Attribute.TypeCompound(targetContainerType, List.of(p),
 850                         ((Attribute.TypeCompound)annotations.head).position);
 851 
 852                 JCAnnotation annoTree = m.TypeAnnotation(at);
 853                 if (!chk.validateAnnotationDeferErrors(annoTree))
 854                     log.error(annoTree.pos(), Errors.DuplicateAnnotationInvalidRepeated(origAnnoType));
 855 
 856                 if (!chk.isTypeAnnotation(annoTree, isTypeParam)) {
 857                     log.error(pos, isTypeParam ? Errors.InvalidRepeatableAnnotationNotApplicable(targetContainerType, on)
 858                                                : Errors.InvalidRepeatableAnnotationNotApplicableInContext(targetContainerType));
 859                 }
 860 
 861                 at.setSynthesized(true);
 862 
 863                 @SuppressWarnings("unchecked")
 864                 T x = (T) at;
 865                 return x;
 866             } else {
 867                 Attribute.Compound c = new Attribute.Compound(targetContainerType, List.of(p));
 868                 JCAnnotation annoTree = m.Annotation(c);
 869 
 870                 boolean isRecordMember = (on.flags_field & Flags.RECORD) != 0 || on.enclClass() != null && on.enclClass().isRecord();
 871                 /* if it is a record member we will not issue the error now and wait until annotations on records are
 872                  * checked at Check::validateAnnotation, which will issue it
 873                  */
 874                 if (!chk.annotationApplicable(annoTree, on) && (!isRecordMember || isRecordMember && (on.flags_field & Flags.GENERATED_MEMBER) == 0)) {
 875                     log.error(annoTree.pos(),
 876                               Errors.InvalidRepeatableAnnotationNotApplicable(targetContainerType, on));
 877                 }
 878 
 879                 if (!chk.validateAnnotationDeferErrors(annoTree))
 880                     log.error(annoTree.pos(), Errors.DuplicateAnnotationInvalidRepeated(origAnnoType));
 881 
 882                 c = attributeAnnotation(annoTree, targetContainerType, ctx.env);
 883                 c.setSynthesized(true);
 884 
 885                 @SuppressWarnings("unchecked")
 886                 T x = (T) c;
 887                 return x;
 888             }
 889         } else {
 890             return null; // errors should have been reported elsewhere
 891         }
 892     }
 893 
 894     /**
 895      * Fetches the actual Type that should be the containing annotation.
 896      */
 897     private Type getContainingType(Attribute.Compound currentAnno,
 898                                    DiagnosticPosition pos,
 899                                    boolean reportError)
 900     {
 901         Type origAnnoType = currentAnno.type;
 902         TypeSymbol origAnnoDecl = origAnnoType.tsym;
 903 
 904         // Fetch the Repeatable annotation from the current
 905         // annotation's declaration, or null if it has none
 906         Attribute.Compound ca = origAnnoDecl.getAnnotationTypeMetadata().getRepeatable();
 907         if (ca == null) { // has no Repeatable annotation
 908             if (reportError)
 909                 log.error(pos, Errors.DuplicateAnnotationMissingContainer(origAnnoType));
 910             return null;
 911         }
 912 
 913         return filterSame(extractContainingType(ca, pos, origAnnoDecl),
 914                 origAnnoType);
 915     }
 916 
 917     // returns null if t is same as 's', returns 't' otherwise
 918     private Type filterSame(Type t, Type s) {
 919         if (t == null || s == null) {
 920             return t;
 921         }
 922 
 923         return types.isSameType(t, s) ? null : t;
 924     }
 925 
 926     /** Extract the actual Type to be used for a containing annotation. */
 927     private Type extractContainingType(Attribute.Compound ca,
 928                                        DiagnosticPosition pos,
 929                                        TypeSymbol annoDecl)
 930     {
 931         // The next three checks check that the Repeatable annotation
 932         // on the declaration of the annotation type that is repeating is
 933         // valid.
 934 
 935         // Repeatable must have at least one element
 936         if (ca.values.isEmpty()) {
 937             log.error(pos, Errors.InvalidRepeatableAnnotation(annoDecl));
 938             return null;
 939         }
 940         Pair<MethodSymbol,Attribute> p = ca.values.head;
 941         Name name = p.fst.name;
 942         if (name != names.value) { // should contain only one element, named "value"
 943             log.error(pos, Errors.InvalidRepeatableAnnotation(annoDecl));
 944             return null;
 945         }
 946         if (!(p.snd instanceof Attribute.Class attributeClass)) { // check that the value of "value" is an Attribute.Class
 947             log.error(pos, Errors.InvalidRepeatableAnnotation(annoDecl));
 948             return null;
 949         }
 950 
 951         return attributeClass.getValue();
 952     }
 953 
 954     /* Validate that the suggested targetContainerType Type is a valid
 955      * container type for repeated instances of originalAnnoType
 956      * annotations. Return null and report errors if this is not the
 957      * case, return the MethodSymbol of the value element in
 958      * targetContainerType if it is suitable (this is needed to
 959      * synthesize the container). */
 960     private MethodSymbol validateContainer(Type targetContainerType,
 961                                            Type originalAnnoType,
 962                                            DiagnosticPosition pos) {
 963         MethodSymbol containerValueSymbol = null;
 964         boolean fatalError = false;
 965 
 966         // Validate that there is a (and only 1) value method
 967         Scope scope = null;
 968         try {
 969             scope = targetContainerType.tsym.members();
 970         } catch (CompletionFailure ex) {
 971             chk.completionError(pos, ex);
 972             return null;
 973         }
 974         int nr_value_elems = 0;
 975         boolean error = false;
 976         for(Symbol elm : scope.getSymbolsByName(names.value)) {
 977             nr_value_elems++;
 978 
 979             if (nr_value_elems == 1 &&
 980                     elm.kind == MTH) {
 981                 containerValueSymbol = (MethodSymbol)elm;
 982             } else {
 983                 error = true;
 984             }
 985         }
 986         if (error) {
 987             log.error(pos,
 988                       Errors.InvalidRepeatableAnnotationMultipleValues(targetContainerType,
 989                                                                        nr_value_elems));
 990             return null;
 991         } else if (nr_value_elems == 0) {
 992             log.error(pos,
 993                       Errors.InvalidRepeatableAnnotationNoValue(targetContainerType));
 994             return null;
 995         }
 996 
 997         // validate that the 'value' element is a method
 998         // probably "impossible" to fail this
 999         if (containerValueSymbol.kind != MTH) {
1000             log.error(pos,
1001                     Errors.InvalidRepeatableAnnotationInvalidValue(targetContainerType));
1002             fatalError = true;
1003         }
1004 
1005         // validate that the 'value' element has the correct return type
1006         // i.e. array of original anno
1007         Type valueRetType = containerValueSymbol.type.getReturnType();
1008         Type expectedType = types.makeArrayType(originalAnnoType);
1009         if (!(types.isArray(valueRetType) &&
1010                 types.isSameType(expectedType, valueRetType))) {
1011             log.error(pos,
1012                       Errors.InvalidRepeatableAnnotationValueReturn(targetContainerType,
1013                                                                     valueRetType,
1014                                                                     expectedType));
1015             fatalError = true;
1016         }
1017 
1018         return fatalError ? null : containerValueSymbol;
1019     }
1020 
1021     private <T extends Attribute.Compound> T makeContainerAnnotation(List<T> toBeReplaced,
1022             AnnotationContext<T> ctx, Symbol sym, boolean isTypeParam)
1023     {
1024         // Process repeated annotations
1025         T validRepeated =
1026                 processRepeatedAnnotations(toBeReplaced, ctx, sym, isTypeParam);
1027 
1028         if (validRepeated != null) {
1029             // Check that the container isn't manually
1030             // present along with repeated instances of
1031             // its contained annotation.
1032             ListBuffer<T> manualContainer = ctx.annotated.get(validRepeated.type.tsym);
1033             if (manualContainer != null) {
1034                 log.error(ctx.pos.get(manualContainer.first()),
1035                           Errors.InvalidRepeatableAnnotationRepeatedAndContainerPresent(manualContainer.first().type.tsym));
1036             }
1037         }
1038 
1039         // A null return will delete the Placeholder
1040         return validRepeated;
1041     }
1042 
1043     /* ******************
1044      * Type annotations *
1045      ********************/
1046 
1047     /**
1048      * Attribute the list of annotations and enter them onto s.
1049      */
1050     public void enterTypeAnnotations(List<JCAnnotation> annotations, Env<AttrContext> env, Symbol s, boolean isTypeParam)
1051     {
1052         Assert.checkNonNull(s, "Symbol argument to actualEnterTypeAnnotations is nul/");
1053         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
1054 
1055         try {
1056             annotateNow(s, annotations, env, true, isTypeParam);
1057         } finally {
1058             log.useSource(prev);
1059         }
1060     }
1061 
1062     /**
1063      * Enqueue tree for scanning of type annotations, attaching to the Symbol sym.
1064      */
1065     public void queueScanTreeAndTypeAnnotate(JCTree tree, Env<AttrContext> env, Symbol sym)
1066     {
1067         Assert.checkNonNull(sym);
1068         normal(() -> tree.accept(new TypeAnnotate(env, sym)));
1069     }
1070 
1071     /**
1072      * Apply the annotations to the particular type.
1073      */
1074     public void annotateTypeSecondStage(JCTree tree, List<JCAnnotation> annotations, Type storeAt) {
1075         typeAnnotation(() -> {
1076             List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
1077             Assert.check(annotations.size() == compounds.size());
1078             // the type already has annotation metadata, but it's empty
1079             Annotations metadata = storeAt.getMetadata(Annotations.class);
1080             Assert.checkNonNull(metadata);
1081             Assert.check(metadata.annotationBuffer().isEmpty());
1082             metadata.annotationBuffer().appendList(compounds);
1083         });
1084     }
1085 
1086     /**
1087      * Apply the annotations to the particular type.
1088      */
1089     public void annotateTypeParameterSecondStage(JCTree tree, List<JCAnnotation> annotations) {
1090         typeAnnotation(() -> {
1091             List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
1092             Assert.check(annotations.size() == compounds.size());
1093         });
1094     }
1095 
1096     /**
1097      * We need to use a TreeScanner, because it is not enough to visit the top-level
1098      * annotations. We also need to visit type arguments, etc.
1099      */
1100     private class TypeAnnotate extends TreeScanner {
1101         private final Env<AttrContext> env;
1102         private final Symbol sym;
1103 
1104         public TypeAnnotate(Env<AttrContext> env, Symbol sym) {
1105 
1106             this.env = env;
1107             this.sym = sym;
1108         }
1109 
1110         @Override
1111         public void visitAnnotatedType(JCAnnotatedType tree) {
1112             enterTypeAnnotations(tree.annotations, env, sym, false);
1113             scan(tree.underlyingType);
1114         }
1115 
1116         @Override
1117         public void visitTypeParameter(JCTypeParameter tree) {
1118             enterTypeAnnotations(tree.annotations, env, sym, true);
1119             scan(tree.bounds);
1120         }
1121 
1122         @Override
1123         public void visitNewArray(JCNewArray tree) {
1124             enterTypeAnnotations(tree.annotations, env, sym, false);
1125             for (List<JCAnnotation> dimAnnos : tree.dimAnnotations)
1126                 enterTypeAnnotations(dimAnnos, env, sym, false);
1127             scan(tree.elemtype);
1128             scan(tree.elems);
1129         }
1130 
1131         @Override
1132         public void visitMethodDef(JCMethodDecl tree) {
1133             scan(tree.mods);
1134             scan(tree.restype);
1135             scan(tree.typarams);
1136             scan(tree.recvparam);
1137             scan(tree.params);
1138             scan(tree.thrown);
1139             scan(tree.defaultValue);
1140             // Do not annotate the body, just the signature.
1141         }
1142 
1143         @Override
1144         public void visitVarDef(JCVariableDecl tree) {
1145             if (sym != null && sym.kind == VAR) {
1146                 // Don't visit a parameter once when the sym is the method
1147                 // and once when the sym is the parameter.
1148                 scan(tree.mods);
1149                 scan(tree.vartype);
1150             }
1151             scan(tree.init);
1152         }
1153 
1154         @Override
1155         public void visitBindingPattern(JCTree.JCBindingPattern tree) {
1156             //type binding pattern's type will be annotated separately, avoid
1157             //adding its annotations into the owning method here (would clash
1158             //with repeatable annotations).
1159         }
1160 
1161         @Override
1162         public void visitClassDef(JCClassDecl tree) {
1163             // We can only hit a classdef if it is declared within
1164             // a method. Ignore it - the class will be visited
1165             // separately later.
1166         }
1167 
1168         @Override
1169         public void visitNewClass(JCNewClass tree) {
1170             scan(tree.encl);
1171             scan(tree.typeargs);
1172             try {
1173                 env.info.isAnonymousNewClass = tree.def != null;
1174                 scan(tree.clazz);
1175             } finally {
1176                 env.info.isAnonymousNewClass = false;
1177             }
1178             scan(tree.args);
1179             // the anonymous class instantiation if any will be visited separately.
1180         }
1181 
1182         @Override
1183         public void visitErroneous(JCErroneous tree) {
1184             if (tree.errs != null) {
1185                 for (JCTree err : tree.errs) {
1186                     scan(err);
1187                 }
1188             }
1189         }
1190     }
1191 
1192     /* *******************
1193      * Completer support *
1194      *********************/
1195 
1196     private AnnotationTypeCompleter theSourceCompleter = new AnnotationTypeCompleter() {
1197         @Override
1198         public void complete(ClassSymbol sym) throws CompletionFailure {
1199             Env<AttrContext> context = typeEnvs.get(sym);
1200             Annotate.this.attributeAnnotationType(context);
1201         }
1202     };
1203 
1204     /* Last stage completer to enter just enough annotations to have a prototype annotation type.
1205      * This currently means entering @Target and @Repeatable.
1206      */
1207     public AnnotationTypeCompleter annotationTypeSourceCompleter() {
1208         return theSourceCompleter;
1209     }
1210 
1211     private void attributeAnnotationType(Env<AttrContext> env) {
1212         Assert.check(((JCClassDecl)env.tree).sym.isAnnotationType(),
1213                 "Trying to annotation type complete a non-annotation type");
1214 
1215         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
1216         try {
1217             JCClassDecl tree = (JCClassDecl)env.tree;
1218             AnnotationTypeVisitor v = new AnnotationTypeVisitor(attr, chk, syms, typeEnvs);
1219             v.scanAnnotationType(tree);
1220             tree.sym.getAnnotationTypeMetadata().setRepeatable(v.repeatable);
1221             tree.sym.getAnnotationTypeMetadata().setTarget(v.target);
1222         } finally {
1223             log.useSource(prev);
1224         }
1225     }
1226 
1227     public Attribute unfinishedDefaultValue() {
1228         return theUnfinishedDefaultValue;
1229     }
1230 
1231     public static interface AnnotationTypeCompleter {
1232         void complete(ClassSymbol sym) throws CompletionFailure;
1233     }
1234 
1235     /** Visitor to determine a prototype annotation type for a class declaring an annotation type.
1236      *
1237      *  <p><b>This is NOT part of any supported API.
1238      *  If you write code that depends on this, you do so at your own risk.
1239      *  This code and its internal interfaces are subject to change or
1240      *  deletion without notice.</b>
1241      */
1242     public class AnnotationTypeVisitor extends TreeScanner {
1243         private Env<AttrContext> env;
1244 
1245         private final Attr attr;
1246         private final Check check;
1247         private final Symtab tab;
1248         private final TypeEnvs typeEnvs;
1249 
1250         private Compound target;
1251         private Compound repeatable;
1252 
1253         public AnnotationTypeVisitor(Attr attr, Check check, Symtab tab, TypeEnvs typeEnvs) {
1254             this.attr = attr;
1255             this.check = check;
1256             this.tab = tab;
1257             this.typeEnvs = typeEnvs;
1258         }
1259 
1260         public Compound getRepeatable() {
1261             return repeatable;
1262         }
1263 
1264         public Compound getTarget() {
1265             return target;
1266         }
1267 
1268         public void scanAnnotationType(JCClassDecl decl) {
1269             visitClassDef(decl);
1270         }
1271 
1272         @Override
1273         public void visitClassDef(JCClassDecl tree) {
1274             Env<AttrContext> prevEnv = env;
1275             env = typeEnvs.get(tree.sym);
1276             try {
1277                 scan(tree.mods); // look for repeatable and target
1278                 // don't descend into body
1279             } finally {
1280                 env = prevEnv;
1281             }
1282         }
1283 
1284         @Override
1285         public void visitAnnotation(JCAnnotation tree) {
1286             Type t = tree.annotationType.type;
1287             if (t == null) {
1288                 t = attr.attribType(tree.annotationType, env);
1289                 tree.annotationType.type = t = check.checkType(tree.annotationType.pos(), t, tab.annotationType);
1290             }
1291 
1292             if (t == tab.annotationTargetType) {
1293                 target = Annotate.this.attributeAnnotation(tree, tab.annotationTargetType, env);
1294             } else if (t == tab.repeatableType) {
1295                 repeatable = Annotate.this.attributeAnnotation(tree, tab.repeatableType, env);
1296             }
1297         }
1298     }
1299 
1300     /** Represents the semantics of an Annotation Type.
1301      *
1302      *  <p><b>This is NOT part of any supported API.
1303      *  If you write code that depends on this, you do so at your own risk.
1304      *  This code and its internal interfaces are subject to change or
1305      *  deletion without notice.</b>
1306      */
1307     public static class AnnotationTypeMetadata {
1308         final ClassSymbol metaDataFor;
1309         private Compound target;
1310         private Compound repeatable;
1311         private AnnotationTypeCompleter annotationTypeCompleter;
1312 
1313         public AnnotationTypeMetadata(ClassSymbol metaDataFor, AnnotationTypeCompleter annotationTypeCompleter) {
1314             this.metaDataFor = metaDataFor;
1315             this.annotationTypeCompleter = annotationTypeCompleter;
1316         }
1317 
1318         private void init() {
1319             // Make sure metaDataFor is member entered
1320             while (!metaDataFor.isCompleted())
1321                 metaDataFor.complete();
1322 
1323             if (annotationTypeCompleter != null) {
1324                 AnnotationTypeCompleter c = annotationTypeCompleter;
1325                 annotationTypeCompleter = null;
1326                 c.complete(metaDataFor);
1327             }
1328         }
1329 
1330         public void complete() {
1331             init();
1332         }
1333 
1334         public Compound getRepeatable() {
1335             init();
1336             return repeatable;
1337         }
1338 
1339         public void setRepeatable(Compound repeatable) {
1340             Assert.checkNull(this.repeatable);
1341             this.repeatable = repeatable;
1342         }
1343 
1344         public Compound getTarget() {
1345             init();
1346             return target;
1347         }
1348 
1349         public void setTarget(Compound target) {
1350             Assert.checkNull(this.target);
1351                 this.target = target;
1352         }
1353 
1354         public Set<MethodSymbol> getAnnotationElements() {
1355             init();
1356             Set<MethodSymbol> members = new LinkedHashSet<>();
1357             WriteableScope s = metaDataFor.members();
1358             Iterable<Symbol> ss = s.getSymbols(NON_RECURSIVE);
1359             for (Symbol sym : ss)
1360                 if (sym.kind == MTH &&
1361                         sym.name != sym.name.table.names.clinit &&
1362                         (sym.flags() & SYNTHETIC) == 0)
1363                     members.add((MethodSymbol)sym);
1364             return members;
1365         }
1366 
1367         public Set<MethodSymbol> getAnnotationElementsWithDefault() {
1368             init();
1369             Set<MethodSymbol> members = getAnnotationElements();
1370             Set<MethodSymbol> res = new LinkedHashSet<>();
1371             for (MethodSymbol m : members)
1372                 if (m.defaultValue != null)
1373                     res.add(m);
1374             return res;
1375         }
1376 
1377         @Override
1378         public String toString() {
1379             return "Annotation type for: " + metaDataFor;
1380         }
1381 
1382         public boolean isMetadataForAnnotationType() { return true; }
1383 
1384         public static AnnotationTypeMetadata notAnAnnotationType() {
1385             return NOT_AN_ANNOTATION_TYPE;
1386         }
1387 
1388         private static final AnnotationTypeMetadata NOT_AN_ANNOTATION_TYPE =
1389                 new AnnotationTypeMetadata(null, null) {
1390                     @Override
1391                     public void complete() {
1392                     } // do nothing
1393 
1394                     @Override
1395                     public String toString() {
1396                         return "Not an annotation type";
1397                     }
1398 
1399                     @Override
1400                     public Set<MethodSymbol> getAnnotationElements() {
1401                         return new LinkedHashSet<>(0);
1402                     }
1403 
1404                     @Override
1405                     public Set<MethodSymbol> getAnnotationElementsWithDefault() {
1406                         return new LinkedHashSet<>(0);
1407                     }
1408 
1409                     @Override
1410                     public boolean isMetadataForAnnotationType() {
1411                         return false;
1412                     }
1413 
1414                     @Override
1415                     public Compound getTarget() {
1416                         return null;
1417                     }
1418 
1419                     @Override
1420                     public Compound getRepeatable() {
1421                         return null;
1422                     }
1423                 };
1424     }
1425 
1426     public void newRound() {
1427         blockCount = 1;
1428     }
1429 
1430     public Queues setQueues(Queues nue) {
1431         Queues stored = new Queues(q, validateQ, typesQ, afterTypesQ);
1432         this.q = nue.q;
1433         this.typesQ = nue.typesQ;
1434         this.afterTypesQ = nue.afterTypesQ;
1435         this.validateQ = nue.validateQ;
1436         return stored;
1437     }
1438 
1439     static class Queues {
1440         private final ListBuffer<Runnable> q;
1441         private final ListBuffer<Runnable> validateQ;
1442         private final ListBuffer<Runnable> typesQ;
1443         private final ListBuffer<Runnable> afterTypesQ;
1444 
1445         public Queues() {
1446             this(new ListBuffer<Runnable>(), new ListBuffer<Runnable>(), new ListBuffer<Runnable>(), new ListBuffer<Runnable>());
1447         }
1448 
1449         public Queues(ListBuffer<Runnable> q, ListBuffer<Runnable> validateQ, ListBuffer<Runnable> typesQ, ListBuffer<Runnable> afterTypesQ) {
1450             this.q = q;
1451             this.validateQ = validateQ;
1452             this.typesQ = typesQ;
1453             this.afterTypesQ = afterTypesQ;
1454         }
1455     }
1456 }