1 /*
   2  * Copyright (c) 1999, 2023, 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.jvm;
  27 
  28 import java.io.*;
  29 import java.net.URI;
  30 import java.net.URISyntaxException;
  31 import java.nio.CharBuffer;
  32 import java.nio.file.ClosedFileSystemException;
  33 import java.util.Arrays;
  34 import java.util.EnumSet;
  35 import java.util.HashMap;
  36 import java.util.HashSet;
  37 import java.util.Map;
  38 import java.util.Set;
  39 import java.util.function.IntFunction;
  40 
  41 import javax.lang.model.element.Modifier;
  42 import javax.lang.model.element.NestingKind;
  43 import javax.tools.JavaFileManager;
  44 import javax.tools.JavaFileObject;
  45 
  46 import com.sun.tools.javac.code.Source;
  47 import com.sun.tools.javac.code.Source.Feature;
  48 import com.sun.tools.javac.code.Type.ClassType.Flavor;
  49 import com.sun.tools.javac.comp.Annotate;
  50 import com.sun.tools.javac.comp.Annotate.AnnotationTypeCompleter;
  51 import com.sun.tools.javac.code.*;
  52 import com.sun.tools.javac.code.Directive.*;
  53 import com.sun.tools.javac.code.Lint.LintCategory;
  54 import com.sun.tools.javac.code.Scope.WriteableScope;
  55 import com.sun.tools.javac.code.Symbol.*;
  56 import com.sun.tools.javac.code.Symtab;
  57 import com.sun.tools.javac.code.Type.*;
  58 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
  59 import com.sun.tools.javac.file.BaseFileManager;
  60 import com.sun.tools.javac.file.PathFileObject;
  61 import com.sun.tools.javac.jvm.ClassFile.Version;
  62 import com.sun.tools.javac.jvm.PoolConstant.NameAndType;
  63 import com.sun.tools.javac.main.Option;
  64 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
  65 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
  66 import com.sun.tools.javac.util.*;
  67 import com.sun.tools.javac.util.ByteBuffer.UnderflowException;
  68 import com.sun.tools.javac.util.DefinedBy.Api;
  69 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
  70 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
  71 
  72 import static com.sun.tools.javac.code.Flags.*;
  73 import static com.sun.tools.javac.code.Kinds.Kind.*;
  74 
  75 import com.sun.tools.javac.code.Scope.LookupKind;
  76 
  77 import static com.sun.tools.javac.code.TypeTag.ARRAY;
  78 import static com.sun.tools.javac.code.TypeTag.CLASS;
  79 import static com.sun.tools.javac.code.TypeTag.TYPEVAR;
  80 import static com.sun.tools.javac.jvm.ClassFile.*;
  81 import static com.sun.tools.javac.jvm.ClassFile.Version.*;
  82 
  83 import static com.sun.tools.javac.main.Option.PARAMETERS;
  84 
  85 /** This class provides operations to read a classfile into an internal
  86  *  representation. The internal representation is anchored in a
  87  *  ClassSymbol which contains in its scope symbol representations
  88  *  for all other definitions in the classfile. Top-level Classes themselves
  89  *  appear as members of the scopes of PackageSymbols.
  90  *
  91  *  <p><b>This is NOT part of any supported API.
  92  *  If you write code that depends on this, you do so at your own risk.
  93  *  This code and its internal interfaces are subject to change or
  94  *  deletion without notice.</b>
  95  */
  96 public class ClassReader {
  97     /** The context key for the class reader. */
  98     protected static final Context.Key<ClassReader> classReaderKey = new Context.Key<>();
  99 
 100     public static final int INITIAL_BUFFER_SIZE = 0x0fff0;
 101 
 102     private final Annotate annotate;
 103 
 104     /** Switch: verbose output.
 105      */
 106     boolean verbose;
 107 
 108     /** Switch: allow modules.
 109      */
 110     boolean allowModules;
 111 
 112     /** Switch: allow primitive classes.
 113      */
 114     boolean allowPrimitiveClasses;
 115 
 116     /** Switch: allow value classes.
 117      */
 118     boolean allowValueClasses;
 119 
 120     /** Switch: allow sealed
 121      */
 122     boolean allowSealedTypes;
 123 
 124     /** Switch: allow records
 125      */
 126     boolean allowRecords;
 127 
 128    /** Lint option: warn about classfile issues
 129      */
 130     boolean lintClassfile;
 131 
 132     /** Switch: warn (instead of error) on illegal UTF-8
 133      */
 134     boolean warnOnIllegalUtf8;
 135 
 136     /** Switch: preserve parameter names from the variable table.
 137      */
 138     public boolean saveParameterNames;
 139 
 140     /**
 141      * The currently selected profile.
 142      */
 143     public final Profile profile;
 144 
 145     /** The log to use for verbose output
 146      */
 147     final Log log;
 148 
 149     /** The symbol table. */
 150     Symtab syms;
 151 
 152     Types types;
 153 
 154     /** The name table. */
 155     final Names names;
 156 
 157     /** Access to files
 158      */
 159     private final JavaFileManager fileManager;
 160 
 161     /** Factory for diagnostics
 162      */
 163     JCDiagnostic.Factory diagFactory;
 164 
 165     DeferredCompletionFailureHandler dcfh;
 166 
 167     /**
 168      * Support for preview language features.
 169      */
 170     Preview preview;
 171 
 172     /** The current scope where type variables are entered.
 173      */
 174     protected WriteableScope typevars;
 175 
 176     private List<InterimUsesDirective> interimUses = List.nil();
 177     private List<InterimProvidesDirective> interimProvides = List.nil();
 178 
 179     /** The path name of the class file currently being read.
 180      */
 181     protected JavaFileObject currentClassFile = null;
 182 
 183     /** The class or method currently being read.
 184      */
 185     protected Symbol currentOwner = null;
 186 
 187     /** The module containing the class currently being read.
 188      */
 189     protected ModuleSymbol currentModule = null;
 190 
 191     /** The buffer containing the currently read class file.
 192      */
 193     ByteBuffer buf = new ByteBuffer(INITIAL_BUFFER_SIZE);
 194 
 195     /** The current input pointer.
 196      */
 197     protected int bp;
 198 
 199     /** The pool reader.
 200      */
 201     PoolReader poolReader;
 202 
 203     /** The major version number of the class file being read. */
 204     int majorVersion;
 205     /** The minor version number of the class file being read. */
 206     int minorVersion;
 207 
 208     /** UTF-8 validation level */
 209     Convert.Validation utf8validation;
 210 
 211     /** A table to hold the constant pool indices for method parameter
 212      * names, as given in LocalVariableTable attributes.
 213      */
 214     int[] parameterNameIndicesLvt;
 215 
 216     /**
 217      * A table to hold the constant pool indices for method parameter
 218      * names, as given in the MethodParameters attribute.
 219      */
 220     int[] parameterNameIndicesMp;
 221 
 222     /**
 223      * A table to hold the access flags of the method parameters.
 224      */
 225     int[] parameterAccessFlags;
 226 
 227     /**
 228      * A table to hold annotations for method parameters.
 229      */
 230     ParameterAnnotations[] parameterAnnotations;
 231 
 232     /**
 233      * A holder for parameter annotations.
 234      */
 235     static class ParameterAnnotations {
 236         List<CompoundAnnotationProxy> proxies;
 237 
 238         void add(List<CompoundAnnotationProxy> newAnnotations) {
 239             if (proxies == null) {
 240                 proxies = newAnnotations;
 241             } else {
 242                 proxies = proxies.prependList(newAnnotations);
 243             }
 244         }
 245     }
 246 
 247     /**
 248      * The set of attribute names for which warnings have been generated for the current class
 249      */
 250     Set<Name> warnedAttrs = new HashSet<>();
 251 
 252     /**
 253      * The prototype @Target Attribute.Compound if this class is an annotation annotated with
 254      * {@code @Target}
 255      */
 256     CompoundAnnotationProxy target;
 257 
 258     /**
 259      * The prototype @Repeatable Attribute.Compound if this class is an annotation annotated with
 260      * {@code @Repeatable}
 261      */
 262     CompoundAnnotationProxy repeatable;
 263 
 264     /** Get the ClassReader instance for this invocation. */
 265     public static ClassReader instance(Context context) {
 266         ClassReader instance = context.get(classReaderKey);
 267         if (instance == null)
 268             instance = new ClassReader(context);
 269         return instance;
 270     }
 271 
 272     /** Construct a new class reader. */
 273     @SuppressWarnings("this-escape")
 274     protected ClassReader(Context context) {
 275         context.put(classReaderKey, this);
 276         annotate = Annotate.instance(context);
 277         names = Names.instance(context);
 278         syms = Symtab.instance(context);
 279         types = Types.instance(context);
 280         fileManager = context.get(JavaFileManager.class);
 281         if (fileManager == null)
 282             throw new AssertionError("FileManager initialization error");
 283         diagFactory = JCDiagnostic.Factory.instance(context);
 284         dcfh = DeferredCompletionFailureHandler.instance(context);
 285 
 286         log = Log.instance(context);
 287 
 288         Options options = Options.instance(context);
 289         verbose         = options.isSet(Option.VERBOSE);
 290 
 291         Source source = Source.instance(context);
 292         preview = Preview.instance(context);
 293         allowModules     = Feature.MODULES.allowedInSource(source);
 294         allowPrimitiveClasses = Feature.PRIMITIVE_CLASSES.allowedInSource(source) && options.isSet("enablePrimitiveClasses");
 295         allowValueClasses = Feature.VALUE_CLASSES.allowedInSource(source);
 296         allowRecords = Feature.RECORDS.allowedInSource(source);
 297         allowSealedTypes = Feature.SEALED_CLASSES.allowedInSource(source);
 298         warnOnIllegalUtf8 = Feature.WARN_ON_ILLEGAL_UTF8.allowedInSource(source);
 299 
 300         saveParameterNames = options.isSet(PARAMETERS);
 301 
 302         profile = Profile.instance(context);
 303 
 304         typevars = WriteableScope.create(syms.noSymbol);
 305 
 306         lintClassfile = Lint.instance(context).isEnabled(LintCategory.CLASSFILE);
 307 
 308         initAttributeReaders();
 309     }
 310 
 311     /** Add member to class unless it is synthetic.
 312      */
 313     private void enterMember(ClassSymbol c, Symbol sym) {
 314         // Synthetic members are not entered -- reason lost to history (optimization?).
 315         // Lambda methods must be entered because they may have inner classes (which reference them)
 316         if ((sym.flags_field & (SYNTHETIC|BRIDGE)) != SYNTHETIC || sym.name.startsWith(names.lambda))
 317             c.members_field.enter(sym);
 318     }
 319 
 320 /************************************************************************
 321  * Error Diagnoses
 322  ***********************************************************************/
 323 
 324     public ClassFinder.BadClassFile badClassFile(String key, Object... args) {
 325         return badClassFile(diagFactory.fragment(key, args));
 326     }
 327 
 328     public ClassFinder.BadClassFile badClassFile(Fragment fragment) {
 329         return badClassFile(diagFactory.fragment(fragment));
 330     }
 331 
 332     public ClassFinder.BadClassFile badClassFile(JCDiagnostic diagnostic) {
 333         return new ClassFinder.BadClassFile (
 334             currentOwner.enclClass(),
 335             currentClassFile,
 336             diagnostic,
 337             diagFactory,
 338             dcfh);
 339     }
 340 
 341     public ClassFinder.BadEnclosingMethodAttr badEnclosingMethod(Symbol sym) {
 342         return new ClassFinder.BadEnclosingMethodAttr (
 343             currentOwner.enclClass(),
 344             currentClassFile,
 345             diagFactory.fragment(Fragments.BadEnclosingMethod(sym)),
 346             diagFactory,
 347             dcfh);
 348     }
 349 
 350 /************************************************************************
 351  * Buffer Access
 352  ***********************************************************************/
 353 
 354     /** Read a character.
 355      */
 356     char nextChar() {
 357         char res;
 358         try {
 359             res = buf.getChar(bp);
 360         } catch (UnderflowException e) {
 361             throw badClassFile(Fragments.BadClassTruncatedAtOffset(e.getLength()));
 362         }
 363         bp += 2;
 364         return res;
 365     }
 366 
 367     /** Read a byte.
 368      */
 369     int nextByte() {
 370         try {
 371             return buf.getByte(bp++) & 0xFF;
 372         } catch (UnderflowException e) {
 373             throw badClassFile(Fragments.BadClassTruncatedAtOffset(e.getLength()));
 374         }
 375     }
 376 
 377     /** Read an integer.
 378      */
 379     int nextInt() {
 380         int res;
 381         try {
 382             res = buf.getInt(bp);
 383         } catch (UnderflowException e) {
 384             throw badClassFile(Fragments.BadClassTruncatedAtOffset(e.getLength()));
 385         }
 386         bp += 4;
 387         return res;
 388     }
 389 
 390 /************************************************************************
 391  * Constant Pool Access
 392  ***********************************************************************/
 393 
 394     /** Read module_flags.
 395      */
 396     Set<ModuleFlags> readModuleFlags(int flags) {
 397         Set<ModuleFlags> set = EnumSet.noneOf(ModuleFlags.class);
 398         for (ModuleFlags f : ModuleFlags.values()) {
 399             if ((flags & f.value) != 0)
 400                 set.add(f);
 401         }
 402         return set;
 403     }
 404 
 405     /** Read resolution_flags.
 406      */
 407     Set<ModuleResolutionFlags> readModuleResolutionFlags(int flags) {
 408         Set<ModuleResolutionFlags> set = EnumSet.noneOf(ModuleResolutionFlags.class);
 409         for (ModuleResolutionFlags f : ModuleResolutionFlags.values()) {
 410             if ((flags & f.value) != 0)
 411                 set.add(f);
 412         }
 413         return set;
 414     }
 415 
 416     /** Read exports_flags.
 417      */
 418     Set<ExportsFlag> readExportsFlags(int flags) {
 419         Set<ExportsFlag> set = EnumSet.noneOf(ExportsFlag.class);
 420         for (ExportsFlag f: ExportsFlag.values()) {
 421             if ((flags & f.value) != 0)
 422                 set.add(f);
 423         }
 424         return set;
 425     }
 426 
 427     /** Read opens_flags.
 428      */
 429     Set<OpensFlag> readOpensFlags(int flags) {
 430         Set<OpensFlag> set = EnumSet.noneOf(OpensFlag.class);
 431         for (OpensFlag f: OpensFlag.values()) {
 432             if ((flags & f.value) != 0)
 433                 set.add(f);
 434         }
 435         return set;
 436     }
 437 
 438     /** Read requires_flags.
 439      */
 440     Set<RequiresFlag> readRequiresFlags(int flags) {
 441         Set<RequiresFlag> set = EnumSet.noneOf(RequiresFlag.class);
 442         for (RequiresFlag f: RequiresFlag.values()) {
 443             if ((flags & f.value) != 0)
 444                 set.add(f);
 445         }
 446         return set;
 447     }
 448 
 449 /************************************************************************
 450  * Reading Types
 451  ***********************************************************************/
 452 
 453     /** The unread portion of the currently read type is
 454      *  signature[sigp..siglimit-1].
 455      */
 456     byte[] signature;
 457     int sigp;
 458     int siglimit;
 459     boolean sigEnterPhase = false;
 460 
 461     /** Convert signature to type, where signature is a byte array segment.
 462      */
 463     Type sigToType(byte[] sig, int offset, int len) {
 464         signature = sig;
 465         sigp = offset;
 466         siglimit = offset + len;
 467         return sigToType();
 468     }
 469 
 470     /** Convert signature to type, where signature is implicit.
 471      */
 472     Type sigToType() {
 473         switch ((char) signature[sigp]) {
 474         case 'T':
 475             sigp++;
 476             int start = sigp;
 477             while (signature[sigp] != ';') sigp++;
 478             sigp++;
 479             return sigEnterPhase
 480                 ? Type.noType
 481                 : findTypeVar(readName(signature, start, sigp - 1 - start));
 482         case '+': {
 483             sigp++;
 484             Type t = sigToType();
 485             return new WildcardType(t, BoundKind.EXTENDS, syms.boundClass);
 486         }
 487         case '*':
 488             sigp++;
 489             return new WildcardType(syms.objectType, BoundKind.UNBOUND,
 490                                     syms.boundClass);
 491         case '-': {
 492             sigp++;
 493             Type t = sigToType();
 494             return new WildcardType(t, BoundKind.SUPER, syms.boundClass);
 495         }
 496         case 'B':
 497             sigp++;
 498             return syms.byteType;
 499         case 'C':
 500             sigp++;
 501             return syms.charType;
 502         case 'D':
 503             sigp++;
 504             return syms.doubleType;
 505         case 'F':
 506             sigp++;
 507             return syms.floatType;
 508         case 'I':
 509             sigp++;
 510             return syms.intType;
 511         case 'J':
 512             sigp++;
 513             return syms.longType;
 514         case 'Q':
 515         case 'L':
 516             {
 517                 // int oldsigp = sigp;
 518                 if ((char) signature[sigp] == 'Q' && !allowPrimitiveClasses) {
 519                     throw badClassFile("bad.class.signature",
 520                                        quoteBadSignature());
 521                 }
 522                 Type t = classSigToType();
 523                 if (sigp < siglimit && signature[sigp] == '.')
 524                     throw badClassFile("deprecated inner class signature syntax " +
 525                                        "(please recompile from source)");
 526                 /*
 527                 System.err.println(" decoded " +
 528                                    new String(signature, oldsigp, sigp-oldsigp) +
 529                                    " => " + t + " outer " + t.outer());
 530                 */
 531                 return t;
 532             }
 533         case 'S':
 534             sigp++;
 535             return syms.shortType;
 536         case 'V':
 537             sigp++;
 538             return syms.voidType;
 539         case 'Z':
 540             sigp++;
 541             return syms.booleanType;
 542         case '[':
 543             sigp++;
 544             return new ArrayType(sigToType(), syms.arrayClass);
 545         case '(':
 546             sigp++;
 547             List<Type> argtypes = sigToTypes(')');
 548             Type restype = sigToType();
 549             List<Type> thrown = List.nil();
 550             while (sigp < siglimit && signature[sigp] == '^') {
 551                 sigp++;
 552                 thrown = thrown.prepend(sigToType());
 553             }
 554             // if there is a typevar in the throws clause we should state it.
 555             for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) {
 556                 if (l.head.hasTag(TYPEVAR)) {
 557                     l.head.tsym.flags_field |= THROWS;
 558                 }
 559             }
 560             return new MethodType(argtypes,
 561                                   restype,
 562                                   thrown.reverse(),
 563                                   syms.methodClass);
 564         case '<':
 565             typevars = typevars.dup(currentOwner);
 566             Type poly = new ForAll(sigToTypeParams(), sigToType());
 567             typevars = typevars.leave();
 568             return poly;
 569         default:
 570             throw badClassFile("bad.signature", quoteBadSignature());
 571         }
 572     }
 573 
 574     byte[] signatureBuffer = new byte[0];
 575     int sbp = 0;
 576     /** Convert class signature to type, where signature is implicit.
 577      */
 578     Type classSigToType() {
 579         byte prefix = signature[sigp];
 580         if (prefix != 'L' && (!allowPrimitiveClasses || prefix != 'Q'))
 581             throw badClassFile("bad.class.signature", quoteBadSignature());
 582         sigp++;
 583         Type outer = Type.noType;
 584         Name name;
 585         ClassType.Flavor flavor;
 586         int startSbp = sbp;
 587 
 588         while (true) {
 589             final byte c = signature[sigp++];
 590             switch (c) {
 591 
 592             case ';': {         // end
 593                 ClassSymbol t = enterClass(readName(signatureBuffer,
 594                                                          startSbp,
 595                                                          sbp - startSbp));
 596 
 597                 // We are seeing QFoo; or LFoo; The name itself does not shine any light on default val-refness
 598                 flavor = prefix == 'L' ? Flavor.L_TypeOf_X : Flavor.Q_TypeOf_X;
 599                 try {
 600                     if (outer == Type.noType) {
 601                         ClassType et = (ClassType) t.erasure(types);
 602                         // Todo: This spews out more objects than before, i.e no reuse with identical flavor
 603                         return new ClassType(et.getEnclosingType(), List.nil(), et.tsym, et.getMetadata(), flavor);
 604                     }
 605                     return new ClassType(outer, List.nil(), t, List.nil(), flavor);
 606                 } finally {
 607                     sbp = startSbp;
 608                 }
 609             }
 610 
 611             case '<':           // generic arguments
 612                 ClassSymbol t = enterClass(readName(signatureBuffer,
 613                                                          startSbp,
 614                                                          sbp - startSbp));
 615                 // We are seeing QFoo; or LFoo; The name itself does not shine any light on default val-refness
 616                 flavor = prefix == 'L' ? Flavor.L_TypeOf_X : Flavor.Q_TypeOf_X;
 617                 outer = new ClassType(outer, sigToTypes('>'), t, List.nil(), flavor) {
 618                         boolean completed = false;
 619                         @Override @DefinedBy(Api.LANGUAGE_MODEL)
 620                         public Type getEnclosingType() {
 621                             if (!completed) {
 622                                 completed = true;
 623                                 tsym.apiComplete();
 624                                 Type enclosingType = tsym.type.getEnclosingType();
 625                                 if (enclosingType != Type.noType) {
 626                                     List<Type> typeArgs =
 627                                         super.getEnclosingType().allparams();
 628                                     List<Type> typeParams =
 629                                         enclosingType.allparams();
 630                                     if (typeParams.length() != typeArgs.length()) {
 631                                         // no "rare" types
 632                                         super.setEnclosingType(types.erasure(enclosingType));
 633                                     } else {
 634                                         super.setEnclosingType(types.subst(enclosingType,
 635                                                                            typeParams,
 636                                                                            typeArgs));
 637                                     }
 638                                 } else {
 639                                     super.setEnclosingType(Type.noType);
 640                                 }
 641                             }
 642                             return super.getEnclosingType();
 643                         }
 644                         @Override
 645                         public void setEnclosingType(Type outer) {
 646                             throw new UnsupportedOperationException();
 647                         }
 648                     };
 649                 switch (signature[sigp++]) {
 650                 case ';':
 651                     if (sigp < siglimit && signature[sigp] == '.') {
 652                         // support old-style GJC signatures
 653                         // The signature produced was
 654                         // Lfoo/Outer<Lfoo/X;>;.Lfoo/Outer$Inner<Lfoo/Y;>;
 655                         // rather than say
 656                         // Lfoo/Outer<Lfoo/X;>.Inner<Lfoo/Y;>;
 657                         // so we skip past ".Lfoo/Outer$"
 658                         sigp += (sbp - startSbp) + // "foo/Outer"
 659                             3;  // ".L" and "$"
 660                         signatureBuffer[sbp++] = (byte)'$';
 661                         break;
 662                     } else {
 663                         sbp = startSbp;
 664                         return outer;
 665                     }
 666                 case '.':
 667                     signatureBuffer[sbp++] = (byte)'$';
 668                     break;
 669                 default:
 670                     throw new AssertionError(signature[sigp-1]);
 671                 }
 672                 continue;
 673 
 674             case '.':
 675                 //we have seen an enclosing non-generic class
 676                 if (outer != Type.noType) {
 677                     t = enterClass(readName(signatureBuffer,
 678                                                  startSbp,
 679                                                  sbp - startSbp));
 680                     // We are seeing QFoo; or LFoo; The name itself does not shine any light on default val-refness
 681                     flavor = prefix == 'L' ? Flavor.L_TypeOf_X : Flavor.Q_TypeOf_X;
 682                     outer = new ClassType(outer, List.nil(), t, List.nil(), flavor);
 683                 }
 684                 signatureBuffer[sbp++] = (byte)'$';
 685                 continue;
 686             case '/':
 687                 signatureBuffer[sbp++] = (byte)'.';
 688                 continue;
 689             default:
 690                 signatureBuffer[sbp++] = c;
 691                 continue;
 692             }
 693         }
 694     }
 695 
 696     /** Quote a bogus signature for display inside an error message.
 697      */
 698     String quoteBadSignature() {
 699         String sigString;
 700         try {
 701             sigString = Convert.utf2string(signature, sigp, siglimit - sigp, Convert.Validation.NONE);
 702         } catch (InvalidUtfException e) {
 703             throw new AssertionError(e);
 704         }
 705         if (sigString.length() > 32)
 706             sigString = sigString.substring(0, 32) + "...";
 707         return "\"" + sigString + "\"";
 708     }
 709 
 710     /** Convert (implicit) signature to list of types
 711      *  until `terminator' is encountered.
 712      */
 713     List<Type> sigToTypes(char terminator) {
 714         List<Type> head = List.of(null);
 715         List<Type> tail = head;
 716         while (signature[sigp] != terminator)
 717             tail = tail.setTail(List.of(sigToType()));
 718         sigp++;
 719         return head.tail;
 720     }
 721 
 722     /** Convert signature to type parameters, where signature is a byte
 723      *  array segment.
 724      */
 725     List<Type> sigToTypeParams(byte[] sig, int offset, int len) {
 726         signature = sig;
 727         sigp = offset;
 728         siglimit = offset + len;
 729         return sigToTypeParams();
 730     }
 731 
 732     /** Convert signature to type parameters, where signature is implicit.
 733      */
 734     List<Type> sigToTypeParams() {
 735         List<Type> tvars = List.nil();
 736         if (signature[sigp] == '<') {
 737             sigp++;
 738             int start = sigp;
 739             sigEnterPhase = true;
 740             while (signature[sigp] != '>')
 741                 tvars = tvars.prepend(sigToTypeParam());
 742             sigEnterPhase = false;
 743             sigp = start;
 744             while (signature[sigp] != '>')
 745                 sigToTypeParam();
 746             sigp++;
 747         }
 748         return tvars.reverse();
 749     }
 750 
 751     /** Convert (implicit) signature to type parameter.
 752      */
 753     Type sigToTypeParam() {
 754         int start = sigp;
 755         while (signature[sigp] != ':') sigp++;
 756         Name name = readName(signature, start, sigp - start);
 757         TypeVar tvar;
 758         if (sigEnterPhase) {
 759             tvar = new TypeVar(name, currentOwner, syms.botType);
 760             typevars.enter(tvar.tsym);
 761         } else {
 762             tvar = (TypeVar)findTypeVar(name);
 763         }
 764         List<Type> bounds = List.nil();
 765         boolean allInterfaces = false;
 766         if (signature[sigp] == ':' && signature[sigp+1] == ':') {
 767             sigp++;
 768             allInterfaces = true;
 769         }
 770         while (signature[sigp] == ':') {
 771             sigp++;
 772             bounds = bounds.prepend(sigToType());
 773         }
 774         if (!sigEnterPhase) {
 775             types.setBounds(tvar, bounds.reverse(), allInterfaces);
 776         }
 777         return tvar;
 778     }
 779 
 780     /** Find type variable with given name in `typevars' scope.
 781      */
 782     Type findTypeVar(Name name) {
 783         Symbol s = typevars.findFirst(name);
 784         if (s != null) {
 785             return s.type;
 786         } else {
 787             if (readingClassAttr) {
 788                 // While reading the class attribute, the supertypes
 789                 // might refer to a type variable from an enclosing element
 790                 // (method or class).
 791                 // If the type variable is defined in the enclosing class,
 792                 // we can actually find it in
 793                 // currentOwner.owner.type.getTypeArguments()
 794                 // However, until we have read the enclosing method attribute
 795                 // we don't know for sure if this owner is correct.  It could
 796                 // be a method and there is no way to tell before reading the
 797                 // enclosing method attribute.
 798                 TypeVar t = new TypeVar(name, currentOwner, syms.botType);
 799                 missingTypeVariables = missingTypeVariables.prepend(t);
 800                 // System.err.println("Missing type var " + name);
 801                 return t;
 802             }
 803             throw badClassFile("undecl.type.var", name);
 804         }
 805     }
 806 
 807     private Name readName(byte[] buf, int off, int len) {
 808         try {
 809             return names.fromUtf(buf, off, len, utf8validation);
 810         } catch (InvalidUtfException e) {
 811             if (warnOnIllegalUtf8) {
 812                 log.warning(Warnings.InvalidUtf8InClassfile(currentClassFile,
 813                     Fragments.BadUtf8ByteSequenceAt(sigp)));
 814                 return names.fromUtfLax(buf, off, len);
 815             }
 816             throw badClassFile(Fragments.BadUtf8ByteSequenceAt(sigp));
 817         }
 818     }
 819 
 820 /************************************************************************
 821  * Reading Attributes
 822  ***********************************************************************/
 823 
 824     protected enum AttributeKind { CLASS, MEMBER }
 825 
 826     protected abstract class AttributeReader {
 827         protected AttributeReader(Name name, ClassFile.Version version, Set<AttributeKind> kinds) {
 828             this.name = name;
 829             this.version = version;
 830             this.kinds = kinds;
 831         }
 832 
 833         protected boolean accepts(AttributeKind kind) {
 834             if (kinds.contains(kind)) {
 835                 if (majorVersion > version.major || (majorVersion == version.major && minorVersion >= version.minor))
 836                     return true;
 837 
 838                 if (lintClassfile && !warnedAttrs.contains(name)) {
 839                     JavaFileObject prev = log.useSource(currentClassFile);
 840                     try {
 841                         log.warning(LintCategory.CLASSFILE, (DiagnosticPosition) null,
 842                                     Warnings.FutureAttr(name, version.major, version.minor, majorVersion, minorVersion));
 843                     } finally {
 844                         log.useSource(prev);
 845                     }
 846                     warnedAttrs.add(name);
 847                 }
 848             }
 849             return false;
 850         }
 851 
 852         protected abstract void read(Symbol sym, int attrLen);
 853 
 854         protected final Name name;
 855         protected final ClassFile.Version version;
 856         protected final Set<AttributeKind> kinds;
 857     }
 858 
 859     protected Set<AttributeKind> CLASS_ATTRIBUTE =
 860             EnumSet.of(AttributeKind.CLASS);
 861     protected Set<AttributeKind> MEMBER_ATTRIBUTE =
 862             EnumSet.of(AttributeKind.MEMBER);
 863     protected Set<AttributeKind> CLASS_OR_MEMBER_ATTRIBUTE =
 864             EnumSet.of(AttributeKind.CLASS, AttributeKind.MEMBER);
 865 
 866     protected Map<Name, AttributeReader> attributeReaders = new HashMap<>();
 867 
 868     private void initAttributeReaders() {
 869         AttributeReader[] readers = {
 870             // v45.3 attributes
 871 
 872             new AttributeReader(names.Code, V45_3, MEMBER_ATTRIBUTE) {
 873                 protected void read(Symbol sym, int attrLen) {
 874                     if (sym.isInitOrVNew() && sym.type.getParameterTypes().size() == 0) {
 875                         try {
 876                             int code_length = buf.getInt(bp + 4);
 877                             if ((code_length == 1 && buf.getByte(bp + 8) == (byte) ByteCodes.return_) ||
 878                                 (code_length == 5 && buf.getByte(bp + 8) == ByteCodes.aload_0 &&
 879                                     buf.getByte(bp + 9) == (byte) ByteCodes.invokespecial &&
 880                                             buf.getByte(bp + 12) == (byte) ByteCodes.return_)) {
 881                                 sym.flags_field |= EMPTYNOARGCONSTR;
 882                             }
 883                         } catch (UnderflowException e) {
 884                             throw badClassFile("bad.class.truncated.at.offset", Integer.toString(e.getLength()));
 885                         }
 886                     }
 887                     if (saveParameterNames)
 888                         ((MethodSymbol)sym).code = readCode(sym);
 889                     else
 890                         bp = bp + attrLen;
 891                 }
 892             },
 893 
 894             new AttributeReader(names.ConstantValue, V45_3, MEMBER_ATTRIBUTE) {
 895                 protected void read(Symbol sym, int attrLen) {
 896                     Object v = poolReader.getConstant(nextChar());
 897                     // Ignore ConstantValue attribute if field not final.
 898                     if ((sym.flags() & FINAL) == 0) {
 899                         return;
 900                     }
 901                     VarSymbol var = (VarSymbol) sym;
 902                     switch (var.type.getTag()) {
 903                        case BOOLEAN:
 904                        case BYTE:
 905                        case CHAR:
 906                        case SHORT:
 907                        case INT:
 908                            checkType(var, Integer.class, v);
 909                            break;
 910                        case LONG:
 911                            checkType(var, Long.class, v);
 912                            break;
 913                        case FLOAT:
 914                            checkType(var, Float.class, v);
 915                            break;
 916                        case DOUBLE:
 917                            checkType(var, Double.class, v);
 918                            break;
 919                        case CLASS:
 920                            if (var.type.tsym == syms.stringType.tsym) {
 921                                checkType(var, String.class, v);
 922                            } else {
 923                                throw badClassFile("bad.constant.value.type", var.type);
 924                            }
 925                            break;
 926                        default:
 927                            // ignore ConstantValue attribute if type is not primitive or String
 928                            return;
 929                     }
 930                     if (v instanceof Integer intVal && !var.type.getTag().checkRange(intVal)) {
 931                         throw badClassFile("bad.constant.range", v, var, var.type);
 932                     }
 933                     var.setData(v);
 934                 }
 935 
 936                 void checkType(Symbol var, Class<?> clazz, Object value) {
 937                     if (!clazz.isInstance(value)) {
 938                         throw badClassFile("bad.constant.value", value, var, clazz.getSimpleName());
 939                     }
 940                 }
 941             },
 942 
 943             new AttributeReader(names.Deprecated, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
 944                 protected void read(Symbol sym, int attrLen) {
 945                     Symbol s = sym.owner.kind == MDL ? sym.owner : sym;
 946 
 947                     s.flags_field |= DEPRECATED;
 948                 }
 949             },
 950 
 951             new AttributeReader(names.Exceptions, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
 952                 protected void read(Symbol sym, int attrLen) {
 953                     int nexceptions = nextChar();
 954                     List<Type> thrown = List.nil();
 955                     for (int j = 0; j < nexceptions; j++)
 956                         thrown = thrown.prepend(poolReader.getClass(nextChar()).type);
 957                     if (sym.type.getThrownTypes().isEmpty())
 958                         sym.type.asMethodType().thrown = thrown.reverse();
 959                 }
 960             },
 961 
 962             new AttributeReader(names.InnerClasses, V45_3, CLASS_ATTRIBUTE) {
 963                 protected void read(Symbol sym, int attrLen) {
 964                     ClassSymbol c = (ClassSymbol) sym;
 965                     if (currentModule.module_info == c) {
 966                         //prevent entering the classes too soon:
 967                         skipInnerClasses();
 968                     } else {
 969                         readInnerClasses(c);
 970                     }
 971                 }
 972             },
 973 
 974             new AttributeReader(names.LocalVariableTable, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
 975                 protected void read(Symbol sym, int attrLen) {
 976                     int newbp = bp + attrLen;
 977                     if (saveParameterNames) {
 978                         // Pick up parameter names from the variable table.
 979                         // Parameter names are not explicitly identified as such,
 980                         // but all parameter name entries in the LocalVariableTable
 981                         // have a start_pc of 0.  Therefore, we record the name
 982                         // indices of all slots with a start_pc of zero in the
 983                         // parameterNameIndices array.
 984                         // Note that this implicitly honors the JVMS spec that
 985                         // there may be more than one LocalVariableTable, and that
 986                         // there is no specified ordering for the entries.
 987                         int numEntries = nextChar();
 988                         for (int i = 0; i < numEntries; i++) {
 989                             int start_pc = nextChar();
 990                             int length = nextChar();
 991                             int nameIndex = nextChar();
 992                             int sigIndex = nextChar();
 993                             int register = nextChar();
 994                             if (start_pc == 0) {
 995                                 // ensure array large enough
 996                                 if (register >= parameterNameIndicesLvt.length) {
 997                                     int newSize =
 998                                             Math.max(register + 1, parameterNameIndicesLvt.length + 8);
 999                                     parameterNameIndicesLvt =
1000                                             Arrays.copyOf(parameterNameIndicesLvt, newSize);
1001                                 }
1002                                 parameterNameIndicesLvt[register] = nameIndex;
1003                             }
1004                         }
1005                     }
1006                     bp = newbp;
1007                 }
1008             },
1009 
1010             new AttributeReader(names.SourceFile, V45_3, CLASS_ATTRIBUTE) {
1011                 protected void read(Symbol sym, int attrLen) {
1012                     ClassSymbol c = (ClassSymbol) sym;
1013                     Name n = poolReader.getName(nextChar());
1014                     c.sourcefile = new SourceFileObject(n);
1015                     // If the class is a toplevel class, originating from a Java source file,
1016                     // but the class name does not match the file name, then it is
1017                     // an auxiliary class.
1018                     String sn = n.toString();
1019                     if (c.owner.kind == PCK &&
1020                         sn.endsWith(".java") &&
1021                         !sn.equals(c.name.toString()+".java")) {
1022                         c.flags_field |= AUXILIARY;
1023                     }
1024                 }
1025             },
1026 
1027             new AttributeReader(names.Synthetic, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
1028                 protected void read(Symbol sym, int attrLen) {
1029                     sym.flags_field |= SYNTHETIC;
1030                 }
1031             },
1032 
1033             // standard v49 attributes
1034 
1035             new AttributeReader(names.EnclosingMethod, V49, CLASS_ATTRIBUTE) {
1036                 protected void read(Symbol sym, int attrLen) {
1037                     int newbp = bp + attrLen;
1038                     readEnclosingMethodAttr(sym);
1039                     bp = newbp;
1040                 }
1041             },
1042 
1043             new AttributeReader(names.Signature, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1044                 protected void read(Symbol sym, int attrLen) {
1045                     if (sym.kind == TYP) {
1046                         ClassSymbol c = (ClassSymbol) sym;
1047                         readingClassAttr = true;
1048                         try {
1049                             ClassType ct1 = (ClassType)c.type;
1050                             Assert.check(c == currentOwner);
1051                             ct1.typarams_field = poolReader.getName(nextChar())
1052                                     .map(ClassReader.this::sigToTypeParams);
1053                             ct1.supertype_field = sigToType();
1054                             ListBuffer<Type> is = new ListBuffer<>();
1055                             while (sigp != siglimit) is.append(sigToType());
1056                             ct1.interfaces_field = is.toList();
1057                         } finally {
1058                             readingClassAttr = false;
1059                         }
1060                     } else {
1061                         List<Type> thrown = sym.type.getThrownTypes();
1062                         sym.type = poolReader.getType(nextChar());
1063                         //- System.err.println(" # " + sym.type);
1064                         if (sym.kind == MTH && sym.type.getThrownTypes().isEmpty())
1065                             sym.type.asMethodType().thrown = thrown;
1066                         // Map value class factory methods back to constructors for the benefit of earlier pipeline stages
1067                         if (sym.kind == MTH && sym.name == names.vnew && !sym.type.getReturnType().hasTag(TypeTag.VOID)) {
1068                             sym.type = new MethodType(sym.type.getParameterTypes(),
1069                                     syms.voidType,
1070                                     sym.type.getThrownTypes(),
1071                                     syms.methodClass);
1072                         }
1073 
1074                     }
1075                 }
1076             },
1077 
1078             // v49 annotation attributes
1079 
1080             new AttributeReader(names.AnnotationDefault, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1081                 protected void read(Symbol sym, int attrLen) {
1082                     attachAnnotationDefault(sym);
1083                 }
1084             },
1085 
1086             new AttributeReader(names.RuntimeInvisibleAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1087                 protected void read(Symbol sym, int attrLen) {
1088                     attachAnnotations(sym);
1089                 }
1090             },
1091 
1092             new AttributeReader(names.RuntimeInvisibleParameterAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1093                 protected void read(Symbol sym, int attrLen) {
1094                     readParameterAnnotations(sym);
1095                 }
1096             },
1097 
1098             new AttributeReader(names.RuntimeVisibleAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1099                 protected void read(Symbol sym, int attrLen) {
1100                     attachAnnotations(sym);
1101                 }
1102             },
1103 
1104             new AttributeReader(names.RuntimeVisibleParameterAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1105                 protected void read(Symbol sym, int attrLen) {
1106                     readParameterAnnotations(sym);
1107                 }
1108             },
1109 
1110             // additional "legacy" v49 attributes, superseded by flags
1111 
1112             new AttributeReader(names.Annotation, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1113                 protected void read(Symbol sym, int attrLen) {
1114                     sym.flags_field |= ANNOTATION;
1115                 }
1116             },
1117 
1118             new AttributeReader(names.Bridge, V49, MEMBER_ATTRIBUTE) {
1119                 protected void read(Symbol sym, int attrLen) {
1120                     sym.flags_field |= BRIDGE;
1121                 }
1122             },
1123 
1124             new AttributeReader(names.Enum, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1125                 protected void read(Symbol sym, int attrLen) {
1126                     sym.flags_field |= ENUM;
1127                 }
1128             },
1129 
1130             new AttributeReader(names.Varargs, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
1131                 protected void read(Symbol sym, int attrLen) {
1132                     sym.flags_field |= VARARGS;
1133                 }
1134             },
1135 
1136             new AttributeReader(names.RuntimeVisibleTypeAnnotations, V52, CLASS_OR_MEMBER_ATTRIBUTE) {
1137                 protected void read(Symbol sym, int attrLen) {
1138                     attachTypeAnnotations(sym);
1139                 }
1140             },
1141 
1142             new AttributeReader(names.RuntimeInvisibleTypeAnnotations, V52, CLASS_OR_MEMBER_ATTRIBUTE) {
1143                 protected void read(Symbol sym, int attrLen) {
1144                     attachTypeAnnotations(sym);
1145                 }
1146             },
1147 
1148             // The following attributes for a Code attribute are not currently handled
1149             // StackMapTable
1150             // SourceDebugExtension
1151             // LineNumberTable
1152             // LocalVariableTypeTable
1153 
1154             // standard v52 attributes
1155 
1156             new AttributeReader(names.MethodParameters, V52, MEMBER_ATTRIBUTE) {
1157                 protected void read(Symbol sym, int attrlen) {
1158                     int newbp = bp + attrlen;
1159                     if (saveParameterNames) {
1160                         int numEntries = nextByte();
1161                         parameterNameIndicesMp = new int[numEntries];
1162                         parameterAccessFlags = new int[numEntries];
1163                         int index = 0;
1164                         for (int i = 0; i < numEntries; i++) {
1165                             int nameIndex = nextChar();
1166                             int flags = nextChar();
1167                             if ((flags & (Flags.MANDATED | Flags.SYNTHETIC)) != 0) {
1168                                 continue;
1169                             }
1170                             parameterNameIndicesMp[index] = nameIndex;
1171                             parameterAccessFlags[index] = flags;
1172                             index++;
1173                         }
1174                     }
1175                     bp = newbp;
1176                 }
1177             },
1178 
1179             // standard v53 attributes
1180 
1181             new AttributeReader(names.Module, V53, CLASS_ATTRIBUTE) {
1182                 @Override
1183                 protected boolean accepts(AttributeKind kind) {
1184                     return super.accepts(kind) && allowModules;
1185                 }
1186                 protected void read(Symbol sym, int attrLen) {
1187                     if (sym.kind == TYP && sym.owner.kind == MDL) {
1188                         ModuleSymbol msym = (ModuleSymbol) sym.owner;
1189                         ListBuffer<Directive> directives = new ListBuffer<>();
1190 
1191                         Name moduleName = poolReader.peekModuleName(nextChar(), ClassReader.this::readName);
1192                         if (currentModule.name != moduleName) {
1193                             throw badClassFile("module.name.mismatch", moduleName, currentModule.name);
1194                         }
1195 
1196                         Set<ModuleFlags> moduleFlags = readModuleFlags(nextChar());
1197                         msym.flags.addAll(moduleFlags);
1198                         msym.version = optPoolEntry(nextChar(), poolReader::getName, null);
1199 
1200                         ListBuffer<RequiresDirective> requires = new ListBuffer<>();
1201                         int nrequires = nextChar();
1202                         for (int i = 0; i < nrequires; i++) {
1203                             ModuleSymbol rsym = poolReader.getModule(nextChar());
1204                             Set<RequiresFlag> flags = readRequiresFlags(nextChar());
1205                             if (rsym == syms.java_base && majorVersion >= V54.major) {
1206                                 if (flags.contains(RequiresFlag.TRANSITIVE)) {
1207                                     throw badClassFile("bad.requires.flag", RequiresFlag.TRANSITIVE);
1208                                 }
1209                                 if (flags.contains(RequiresFlag.STATIC_PHASE)) {
1210                                     throw badClassFile("bad.requires.flag", RequiresFlag.STATIC_PHASE);
1211                                 }
1212                             }
1213                             nextChar(); // skip compiled version
1214                             requires.add(new RequiresDirective(rsym, flags));
1215                         }
1216                         msym.requires = requires.toList();
1217                         directives.addAll(msym.requires);
1218 
1219                         ListBuffer<ExportsDirective> exports = new ListBuffer<>();
1220                         int nexports = nextChar();
1221                         for (int i = 0; i < nexports; i++) {
1222                             PackageSymbol p = poolReader.getPackage(nextChar());
1223                             Set<ExportsFlag> flags = readExportsFlags(nextChar());
1224                             int nto = nextChar();
1225                             List<ModuleSymbol> to;
1226                             if (nto == 0) {
1227                                 to = null;
1228                             } else {
1229                                 ListBuffer<ModuleSymbol> lb = new ListBuffer<>();
1230                                 for (int t = 0; t < nto; t++)
1231                                     lb.append(poolReader.getModule(nextChar()));
1232                                 to = lb.toList();
1233                             }
1234                             exports.add(new ExportsDirective(p, to, flags));
1235                         }
1236                         msym.exports = exports.toList();
1237                         directives.addAll(msym.exports);
1238                         ListBuffer<OpensDirective> opens = new ListBuffer<>();
1239                         int nopens = nextChar();
1240                         if (nopens != 0 && msym.flags.contains(ModuleFlags.OPEN)) {
1241                             throw badClassFile("module.non.zero.opens", currentModule.name);
1242                         }
1243                         for (int i = 0; i < nopens; i++) {
1244                             PackageSymbol p = poolReader.getPackage(nextChar());
1245                             Set<OpensFlag> flags = readOpensFlags(nextChar());
1246                             int nto = nextChar();
1247                             List<ModuleSymbol> to;
1248                             if (nto == 0) {
1249                                 to = null;
1250                             } else {
1251                                 ListBuffer<ModuleSymbol> lb = new ListBuffer<>();
1252                                 for (int t = 0; t < nto; t++)
1253                                     lb.append(poolReader.getModule(nextChar()));
1254                                 to = lb.toList();
1255                             }
1256                             opens.add(new OpensDirective(p, to, flags));
1257                         }
1258                         msym.opens = opens.toList();
1259                         directives.addAll(msym.opens);
1260 
1261                         msym.directives = directives.toList();
1262 
1263                         ListBuffer<InterimUsesDirective> uses = new ListBuffer<>();
1264                         int nuses = nextChar();
1265                         for (int i = 0; i < nuses; i++) {
1266                             Name srvc = poolReader.peekClassName(nextChar(), this::classNameMapper);
1267                             uses.add(new InterimUsesDirective(srvc));
1268                         }
1269                         interimUses = uses.toList();
1270 
1271                         ListBuffer<InterimProvidesDirective> provides = new ListBuffer<>();
1272                         int nprovides = nextChar();
1273                         for (int p = 0; p < nprovides; p++) {
1274                             Name srvc = poolReader.peekClassName(nextChar(), this::classNameMapper);
1275                             int nimpls = nextChar();
1276                             ListBuffer<Name> impls = new ListBuffer<>();
1277                             for (int i = 0; i < nimpls; i++) {
1278                                 impls.append(poolReader.peekClassName(nextChar(), this::classNameMapper));
1279                             provides.add(new InterimProvidesDirective(srvc, impls.toList()));
1280                             }
1281                         }
1282                         interimProvides = provides.toList();
1283                     }
1284                 }
1285 
1286                 private Name classNameMapper(byte[] arr, int offset, int length) throws InvalidUtfException {
1287                     byte[] buf = ClassFile.internalize(arr, offset, length);
1288                     try {
1289                         return names.fromUtf(buf, 0, buf.length, utf8validation);
1290                     } catch (InvalidUtfException e) {
1291                         if (warnOnIllegalUtf8) {
1292                             log.warning(Warnings.InvalidUtf8InClassfile(currentClassFile,
1293                                 Fragments.BadUtf8ByteSequenceAt(e.getOffset())));
1294                             return names.fromUtfLax(buf, 0, buf.length);
1295                         }
1296                         throw e;
1297                     }
1298                 }
1299             },
1300 
1301             new AttributeReader(names.ModuleResolution, V53, CLASS_ATTRIBUTE) {
1302                 @Override
1303                 protected boolean accepts(AttributeKind kind) {
1304                     return super.accepts(kind) && allowModules;
1305                 }
1306                 protected void read(Symbol sym, int attrLen) {
1307                     if (sym.kind == TYP && sym.owner.kind == MDL) {
1308                         ModuleSymbol msym = (ModuleSymbol) sym.owner;
1309                         msym.resolutionFlags.addAll(readModuleResolutionFlags(nextChar()));
1310                     }
1311                 }
1312             },
1313 
1314             new AttributeReader(names.Record, V58, CLASS_ATTRIBUTE) {
1315                 @Override
1316                 protected boolean accepts(AttributeKind kind) {
1317                     return super.accepts(kind) && allowRecords;
1318                 }
1319                 protected void read(Symbol sym, int attrLen) {
1320                     if (sym.kind == TYP) {
1321                         sym.flags_field |= RECORD;
1322                     }
1323                     int componentCount = nextChar();
1324                     ListBuffer<RecordComponent> components = new ListBuffer<>();
1325                     for (int i = 0; i < componentCount; i++) {
1326                         Name name = poolReader.getName(nextChar());
1327                         Type type = poolReader.getType(nextChar());
1328                         RecordComponent c = new RecordComponent(name, type, sym);
1329                         readAttrs(c, AttributeKind.MEMBER);
1330                         components.add(c);
1331                     }
1332                     ((ClassSymbol) sym).setRecordComponents(components.toList());
1333                 }
1334             },
1335             new AttributeReader(names.PermittedSubclasses, V59, CLASS_ATTRIBUTE) {
1336                 @Override
1337                 protected boolean accepts(AttributeKind kind) {
1338                     return super.accepts(kind) && allowSealedTypes;
1339                 }
1340                 protected void read(Symbol sym, int attrLen) {
1341                     if (sym.kind == TYP) {
1342                         ListBuffer<Symbol> subtypes = new ListBuffer<>();
1343                         int numberOfPermittedSubtypes = nextChar();
1344                         for (int i = 0; i < numberOfPermittedSubtypes; i++) {
1345                             subtypes.add(poolReader.getClass(nextChar()));
1346                         }
1347                         ((ClassSymbol)sym).permitted = subtypes.toList();
1348                     }
1349                 }
1350             },
1351         };
1352 
1353         for (AttributeReader r: readers)
1354             attributeReaders.put(r.name, r);
1355     }
1356 
1357     protected void readEnclosingMethodAttr(Symbol sym) {
1358         // sym is a nested class with an "Enclosing Method" attribute
1359         // remove sym from it's current owners scope and place it in
1360         // the scope specified by the attribute
1361         sym.owner.members().remove(sym);
1362         ClassSymbol self = (ClassSymbol)sym;
1363         ClassSymbol c = poolReader.getClass(nextChar());
1364         NameAndType nt = optPoolEntry(nextChar(), poolReader::getNameAndType, null);
1365 
1366         if (c.members_field == null || c.kind != TYP)
1367             throw badClassFile("bad.enclosing.class", self, c);
1368 
1369         MethodSymbol m = findMethod(nt, c.members_field, self.flags());
1370         if (nt != null && m == null)
1371             throw badEnclosingMethod(self);
1372 
1373         self.name = simpleBinaryName(self.flatname, c.flatname) ;
1374         self.owner = m != null ? m : c;
1375         if (self.name.isEmpty())
1376             self.fullname = names.empty;
1377         else
1378             self.fullname = ClassSymbol.formFullName(self.name, self.owner);
1379 
1380         if (m != null) {
1381             ((ClassType)sym.type).setEnclosingType(m.type);
1382         } else if ((self.flags_field & STATIC) == 0) {
1383             ((ClassType)sym.type).setEnclosingType(c.type);
1384         } else {
1385             ((ClassType)sym.type).setEnclosingType(Type.noType);
1386         }
1387         enterTypevars(self, self.type);
1388         if (!missingTypeVariables.isEmpty()) {
1389             ListBuffer<Type> typeVars =  new ListBuffer<>();
1390             for (Type typevar : missingTypeVariables) {
1391                 typeVars.append(findTypeVar(typevar.tsym.name));
1392             }
1393             foundTypeVariables = typeVars.toList();
1394         } else {
1395             foundTypeVariables = List.nil();
1396         }
1397     }
1398 
1399     // See java.lang.Class
1400     private Name simpleBinaryName(Name self, Name enclosing) {
1401         if (!self.startsWith(enclosing)) {
1402             throw badClassFile("bad.enclosing.method", self);
1403         }
1404 
1405         String simpleBinaryName = self.toString().substring(enclosing.toString().length());
1406         if (simpleBinaryName.length() < 1 || simpleBinaryName.charAt(0) != '$')
1407             throw badClassFile("bad.enclosing.method", self);
1408         int index = 1;
1409         while (index < simpleBinaryName.length() &&
1410                isAsciiDigit(simpleBinaryName.charAt(index)))
1411             index++;
1412         return names.fromString(simpleBinaryName.substring(index));
1413     }
1414 
1415     private MethodSymbol findMethod(NameAndType nt, Scope scope, long flags) {
1416         if (nt == null)
1417             return null;
1418 
1419         MethodType type = nt.type.asMethodType();
1420 
1421         for (Symbol sym : scope.getSymbolsByName(nt.name)) {
1422             if (sym.kind == MTH && isSameBinaryType(sym.type.asMethodType(), type))
1423                 return (MethodSymbol)sym;
1424         }
1425 
1426         if (!names.isInitOrVNew(nt.name))
1427             // not a constructor
1428             return null;
1429         if ((flags & INTERFACE) != 0)
1430             // no enclosing instance
1431             return null;
1432         if (nt.type.getParameterTypes().isEmpty())
1433             // no parameters
1434             return null;
1435 
1436         // A constructor of an inner class.
1437         // Remove the first argument (the enclosing instance)
1438         nt = new NameAndType(nt.name, new MethodType(nt.type.getParameterTypes().tail,
1439                                  nt.type.getReturnType(),
1440                                  nt.type.getThrownTypes(),
1441                                  syms.methodClass));
1442         // Try searching again
1443         return findMethod(nt, scope, flags);
1444     }
1445 
1446     /** Similar to Types.isSameType but avoids completion */
1447     private boolean isSameBinaryType(MethodType mt1, MethodType mt2) {
1448         List<Type> types1 = types.erasure(mt1.getParameterTypes())
1449             .prepend(types.erasure(mt1.getReturnType()));
1450         List<Type> types2 = mt2.getParameterTypes().prepend(mt2.getReturnType());
1451         while (!types1.isEmpty() && !types2.isEmpty()) {
1452             if (types1.head.tsym != types2.head.tsym)
1453                 return false;
1454             types1 = types1.tail;
1455             types2 = types2.tail;
1456         }
1457         return types1.isEmpty() && types2.isEmpty();
1458     }
1459 
1460     /**
1461      * Character.isDigit answers <tt>true</tt> to some non-ascii
1462      * digits.  This one does not.  <b>copied from java.lang.Class</b>
1463      */
1464     private static boolean isAsciiDigit(char c) {
1465         return '0' <= c && c <= '9';
1466     }
1467 
1468     /** Read member attributes.
1469      */
1470     void readMemberAttrs(Symbol sym) {
1471         readAttrs(sym, AttributeKind.MEMBER);
1472     }
1473 
1474     void readAttrs(Symbol sym, AttributeKind kind) {
1475         char ac = nextChar();
1476         for (int i = 0; i < ac; i++) {
1477             Name attrName = poolReader.getName(nextChar());
1478             int attrLen = nextInt();
1479             AttributeReader r = attributeReaders.get(attrName);
1480             if (r != null && r.accepts(kind))
1481                 r.read(sym, attrLen);
1482             else  {
1483                 bp = bp + attrLen;
1484             }
1485         }
1486     }
1487 
1488     private boolean readingClassAttr = false;
1489     private List<Type> missingTypeVariables = List.nil();
1490     private List<Type> foundTypeVariables = List.nil();
1491 
1492     /** Read class attributes.
1493      */
1494     void readClassAttrs(ClassSymbol c) {
1495         readAttrs(c, AttributeKind.CLASS);
1496     }
1497 
1498     /** Read code block.
1499      */
1500     Code readCode(Symbol owner) {
1501         nextChar(); // max_stack
1502         nextChar(); // max_locals
1503         final int  code_length = nextInt();
1504         bp += code_length;
1505         final char exception_table_length = nextChar();
1506         bp += exception_table_length * 8;
1507         readMemberAttrs(owner);
1508         return null;
1509     }
1510 
1511 /************************************************************************
1512  * Reading Java-language annotations
1513  ***********************************************************************/
1514 
1515     /**
1516      * Save annotations.
1517      */
1518     List<CompoundAnnotationProxy> readAnnotations() {
1519         int numAttributes = nextChar();
1520         ListBuffer<CompoundAnnotationProxy> annotations = new ListBuffer<>();
1521         for (int i = 0; i < numAttributes; i++) {
1522             annotations.append(readCompoundAnnotation());
1523         }
1524         return annotations.toList();
1525     }
1526 
1527     /** Attach annotations.
1528      */
1529     void attachAnnotations(final Symbol sym) {
1530         attachAnnotations(sym, readAnnotations());
1531     }
1532 
1533     /**
1534      * Attach annotations.
1535      */
1536     void attachAnnotations(final Symbol sym, List<CompoundAnnotationProxy> annotations) {
1537         if (annotations.isEmpty()) {
1538             return;
1539         }
1540         ListBuffer<CompoundAnnotationProxy> proxies = new ListBuffer<>();
1541         for (CompoundAnnotationProxy proxy : annotations) {
1542             if (proxy.type.tsym.flatName() == syms.proprietaryType.tsym.flatName())
1543                 sym.flags_field |= PROPRIETARY;
1544             else if (proxy.type.tsym.flatName() == syms.profileType.tsym.flatName()) {
1545                 if (profile != Profile.DEFAULT) {
1546                     for (Pair<Name, Attribute> v : proxy.values) {
1547                         if (v.fst == names.value && v.snd instanceof Attribute.Constant constant) {
1548                             if (constant.type == syms.intType && ((Integer) constant.value) > profile.value) {
1549                                 sym.flags_field |= NOT_IN_PROFILE;
1550                             }
1551                         }
1552                     }
1553                 }
1554             } else if (proxy.type.tsym.flatName() == syms.previewFeatureInternalType.tsym.flatName()) {
1555                 sym.flags_field |= PREVIEW_API;
1556                 setFlagIfAttributeTrue(proxy, sym, names.reflective, PREVIEW_REFLECTIVE);
1557             } else if (proxy.type.tsym.flatName() == syms.valueBasedInternalType.tsym.flatName()) {
1558                 Assert.check(sym.kind == TYP);
1559                 sym.flags_field |= VALUE_BASED;
1560             } else {
1561                 if (proxy.type.tsym == syms.annotationTargetType.tsym) {
1562                     target = proxy;
1563                 } else if (proxy.type.tsym == syms.repeatableType.tsym) {
1564                     repeatable = proxy;
1565                 } else if (proxy.type.tsym == syms.deprecatedType.tsym) {
1566                     sym.flags_field |= (DEPRECATED | DEPRECATED_ANNOTATION);
1567                     setFlagIfAttributeTrue(proxy, sym, names.forRemoval, DEPRECATED_REMOVAL);
1568                 }  else if (proxy.type.tsym == syms.previewFeatureType.tsym) {
1569                     sym.flags_field |= PREVIEW_API;
1570                     setFlagIfAttributeTrue(proxy, sym, names.reflective, PREVIEW_REFLECTIVE);
1571                 }  else if (proxy.type.tsym == syms.valueBasedType.tsym && sym.kind == TYP) {
1572                     sym.flags_field |= VALUE_BASED;
1573                 }
1574                 proxies.append(proxy);
1575             }
1576         }
1577         annotate.normal(new AnnotationCompleter(sym, proxies.toList()));
1578     }
1579     //where:
1580         private void setFlagIfAttributeTrue(CompoundAnnotationProxy proxy, Symbol sym, Name attribute, long flag) {
1581             for (Pair<Name, Attribute> v : proxy.values) {
1582                 if (v.fst == attribute && v.snd instanceof Attribute.Constant constant) {
1583                     if (constant.type == syms.booleanType && ((Integer) constant.value) != 0) {
1584                         sym.flags_field |= flag;
1585                     }
1586                 }
1587             }
1588         }
1589 
1590     /** Read parameter annotations.
1591      */
1592     void readParameterAnnotations(Symbol meth) {
1593         int numParameters;
1594         try {
1595             numParameters = buf.getByte(bp++) & 0xFF;
1596         } catch (UnderflowException e) {
1597             throw badClassFile(Fragments.BadClassTruncatedAtOffset(e.getLength()));
1598         }
1599         if (parameterAnnotations == null) {
1600             parameterAnnotations = new ParameterAnnotations[numParameters];
1601         } else if (parameterAnnotations.length != numParameters) {
1602             throw badClassFile("bad.runtime.invisible.param.annotations", meth);
1603         }
1604         for (int pnum = 0; pnum < numParameters; pnum++) {
1605             if (parameterAnnotations[pnum] == null) {
1606                 parameterAnnotations[pnum] = new ParameterAnnotations();
1607             }
1608             parameterAnnotations[pnum].add(readAnnotations());
1609         }
1610     }
1611 
1612     void attachTypeAnnotations(final Symbol sym) {
1613         int numAttributes = nextChar();
1614         if (numAttributes != 0) {
1615             ListBuffer<TypeAnnotationProxy> proxies = new ListBuffer<>();
1616             for (int i = 0; i < numAttributes; i++)
1617                 proxies.append(readTypeAnnotation());
1618             annotate.normal(new TypeAnnotationCompleter(sym, proxies.toList()));
1619         }
1620     }
1621 
1622     /** Attach the default value for an annotation element.
1623      */
1624     void attachAnnotationDefault(final Symbol sym) {
1625         final MethodSymbol meth = (MethodSymbol)sym; // only on methods
1626         final Attribute value = readAttributeValue();
1627 
1628         // The default value is set later during annotation. It might
1629         // be the case that the Symbol sym is annotated _after_ the
1630         // repeating instances that depend on this default value,
1631         // because of this we set an interim value that tells us this
1632         // element (most likely) has a default.
1633         //
1634         // Set interim value for now, reset just before we do this
1635         // properly at annotate time.
1636         meth.defaultValue = value;
1637         annotate.normal(new AnnotationDefaultCompleter(meth, value));
1638     }
1639 
1640     Type readTypeOrClassSymbol(int i) {
1641         return readTypeToProxy(i);
1642     }
1643     Type readTypeToProxy(int i) {
1644         if (currentModule.module_info == currentOwner) {
1645             return new ProxyType(i);
1646         } else {
1647             return poolReader.getType(i);
1648         }
1649     }
1650 
1651     CompoundAnnotationProxy readCompoundAnnotation() {
1652         Type t;
1653         if (currentModule.module_info == currentOwner) {
1654             int cpIndex = nextChar();
1655             t = new ProxyType(cpIndex);
1656         } else {
1657             t = readTypeOrClassSymbol(nextChar());
1658         }
1659         int numFields = nextChar();
1660         ListBuffer<Pair<Name,Attribute>> pairs = new ListBuffer<>();
1661         for (int i=0; i<numFields; i++) {
1662             Name name = poolReader.getName(nextChar());
1663             Attribute value = readAttributeValue();
1664             pairs.append(new Pair<>(name, value));
1665         }
1666         return new CompoundAnnotationProxy(t, pairs.toList());
1667     }
1668 
1669     TypeAnnotationProxy readTypeAnnotation() {
1670         TypeAnnotationPosition position = readPosition();
1671         CompoundAnnotationProxy proxy = readCompoundAnnotation();
1672 
1673         return new TypeAnnotationProxy(proxy, position);
1674     }
1675 
1676     TypeAnnotationPosition readPosition() {
1677         int tag = nextByte(); // TargetType tag is a byte
1678 
1679         if (!TargetType.isValidTargetTypeValue(tag))
1680             throw badClassFile("bad.type.annotation.value", String.format("0x%02X", tag));
1681 
1682         TargetType type = TargetType.fromTargetTypeValue(tag);
1683 
1684         switch (type) {
1685         // instanceof
1686         case INSTANCEOF: {
1687             final int offset = nextChar();
1688             final TypeAnnotationPosition position =
1689                 TypeAnnotationPosition.instanceOf(readTypePath());
1690             position.offset = offset;
1691             return position;
1692         }
1693         // new expression
1694         case NEW: {
1695             final int offset = nextChar();
1696             final TypeAnnotationPosition position =
1697                 TypeAnnotationPosition.newObj(readTypePath());
1698             position.offset = offset;
1699             return position;
1700         }
1701         // constructor/method reference receiver
1702         case CONSTRUCTOR_REFERENCE: {
1703             final int offset = nextChar();
1704             final TypeAnnotationPosition position =
1705                 TypeAnnotationPosition.constructorRef(readTypePath());
1706             position.offset = offset;
1707             return position;
1708         }
1709         case METHOD_REFERENCE: {
1710             final int offset = nextChar();
1711             final TypeAnnotationPosition position =
1712                 TypeAnnotationPosition.methodRef(readTypePath());
1713             position.offset = offset;
1714             return position;
1715         }
1716         // local variable
1717         case LOCAL_VARIABLE: {
1718             final int table_length = nextChar();
1719             final int[] newLvarOffset = new int[table_length];
1720             final int[] newLvarLength = new int[table_length];
1721             final int[] newLvarIndex = new int[table_length];
1722 
1723             for (int i = 0; i < table_length; ++i) {
1724                 newLvarOffset[i] = nextChar();
1725                 newLvarLength[i] = nextChar();
1726                 newLvarIndex[i] = nextChar();
1727             }
1728 
1729             final TypeAnnotationPosition position =
1730                     TypeAnnotationPosition.localVariable(readTypePath());
1731             position.lvarOffset = newLvarOffset;
1732             position.lvarLength = newLvarLength;
1733             position.lvarIndex = newLvarIndex;
1734             return position;
1735         }
1736         // resource variable
1737         case RESOURCE_VARIABLE: {
1738             final int table_length = nextChar();
1739             final int[] newLvarOffset = new int[table_length];
1740             final int[] newLvarLength = new int[table_length];
1741             final int[] newLvarIndex = new int[table_length];
1742 
1743             for (int i = 0; i < table_length; ++i) {
1744                 newLvarOffset[i] = nextChar();
1745                 newLvarLength[i] = nextChar();
1746                 newLvarIndex[i] = nextChar();
1747             }
1748 
1749             final TypeAnnotationPosition position =
1750                     TypeAnnotationPosition.resourceVariable(readTypePath());
1751             position.lvarOffset = newLvarOffset;
1752             position.lvarLength = newLvarLength;
1753             position.lvarIndex = newLvarIndex;
1754             return position;
1755         }
1756         // exception parameter
1757         case EXCEPTION_PARAMETER: {
1758             final int exception_index = nextChar();
1759             final TypeAnnotationPosition position =
1760                 TypeAnnotationPosition.exceptionParameter(readTypePath());
1761             position.setExceptionIndex(exception_index);
1762             return position;
1763         }
1764         // method receiver
1765         case METHOD_RECEIVER:
1766             return TypeAnnotationPosition.methodReceiver(readTypePath());
1767         // type parameter
1768         case CLASS_TYPE_PARAMETER: {
1769             final int parameter_index = nextByte();
1770             return TypeAnnotationPosition
1771                 .typeParameter(readTypePath(), parameter_index);
1772         }
1773         case METHOD_TYPE_PARAMETER: {
1774             final int parameter_index = nextByte();
1775             return TypeAnnotationPosition
1776                 .methodTypeParameter(readTypePath(), parameter_index);
1777         }
1778         // type parameter bound
1779         case CLASS_TYPE_PARAMETER_BOUND: {
1780             final int parameter_index = nextByte();
1781             final int bound_index = nextByte();
1782             return TypeAnnotationPosition
1783                 .typeParameterBound(readTypePath(), parameter_index,
1784                                     bound_index);
1785         }
1786         case METHOD_TYPE_PARAMETER_BOUND: {
1787             final int parameter_index = nextByte();
1788             final int bound_index = nextByte();
1789             return TypeAnnotationPosition
1790                 .methodTypeParameterBound(readTypePath(), parameter_index,
1791                                           bound_index);
1792         }
1793         // class extends or implements clause
1794         case CLASS_EXTENDS: {
1795             final int type_index = nextChar();
1796             return TypeAnnotationPosition.classExtends(readTypePath(),
1797                                                        type_index);
1798         }
1799         // throws
1800         case THROWS: {
1801             final int type_index = nextChar();
1802             return TypeAnnotationPosition.methodThrows(readTypePath(),
1803                                                        type_index);
1804         }
1805         // method parameter
1806         case METHOD_FORMAL_PARAMETER: {
1807             final int parameter_index = nextByte();
1808             return TypeAnnotationPosition.methodParameter(readTypePath(),
1809                                                           parameter_index);
1810         }
1811         // type cast
1812         case CAST: {
1813             final int offset = nextChar();
1814             final int type_index = nextByte();
1815             final TypeAnnotationPosition position =
1816                 TypeAnnotationPosition.typeCast(readTypePath(), type_index);
1817             position.offset = offset;
1818             return position;
1819         }
1820         // method/constructor/reference type argument
1821         case CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT: {
1822             final int offset = nextChar();
1823             final int type_index = nextByte();
1824             final TypeAnnotationPosition position = TypeAnnotationPosition
1825                 .constructorInvocationTypeArg(readTypePath(), type_index);
1826             position.offset = offset;
1827             return position;
1828         }
1829         case METHOD_INVOCATION_TYPE_ARGUMENT: {
1830             final int offset = nextChar();
1831             final int type_index = nextByte();
1832             final TypeAnnotationPosition position = TypeAnnotationPosition
1833                 .methodInvocationTypeArg(readTypePath(), type_index);
1834             position.offset = offset;
1835             return position;
1836         }
1837         case CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT: {
1838             final int offset = nextChar();
1839             final int type_index = nextByte();
1840             final TypeAnnotationPosition position = TypeAnnotationPosition
1841                 .constructorRefTypeArg(readTypePath(), type_index);
1842             position.offset = offset;
1843             return position;
1844         }
1845         case METHOD_REFERENCE_TYPE_ARGUMENT: {
1846             final int offset = nextChar();
1847             final int type_index = nextByte();
1848             final TypeAnnotationPosition position = TypeAnnotationPosition
1849                 .methodRefTypeArg(readTypePath(), type_index);
1850             position.offset = offset;
1851             return position;
1852         }
1853         // We don't need to worry about these
1854         case METHOD_RETURN:
1855             return TypeAnnotationPosition.methodReturn(readTypePath());
1856         case FIELD:
1857             return TypeAnnotationPosition.field(readTypePath());
1858         case UNKNOWN:
1859             throw new AssertionError("jvm.ClassReader: UNKNOWN target type should never occur!");
1860         default:
1861             throw new AssertionError("jvm.ClassReader: Unknown target type for position: " + type);
1862         }
1863     }
1864 
1865     List<TypeAnnotationPosition.TypePathEntry> readTypePath() {
1866         int len = nextByte();
1867         ListBuffer<Integer> loc = new ListBuffer<>();
1868         for (int i = 0; i < len * TypeAnnotationPosition.TypePathEntry.bytesPerEntry; ++i)
1869             loc = loc.append(nextByte());
1870 
1871         return TypeAnnotationPosition.getTypePathFromBinary(loc.toList());
1872 
1873     }
1874 
1875     /**
1876      * Helper function to read an optional pool entry (with given function); this is used while parsing
1877      * InnerClasses and EnclosingMethod attributes, as well as when parsing supertype descriptor,
1878      * as per JVMS.
1879      */
1880     <Z> Z optPoolEntry(int index, IntFunction<Z> poolFunc, Z defaultValue) {
1881         return (index == 0) ?
1882                 defaultValue :
1883                 poolFunc.apply(index);
1884     }
1885 
1886     Attribute readAttributeValue() {
1887         char c;
1888         try {
1889             c = (char)buf.getByte(bp++);
1890         } catch (UnderflowException e) {
1891             throw badClassFile(Fragments.BadClassTruncatedAtOffset(e.getLength()));
1892         }
1893         switch (c) {
1894         case 'B':
1895             return new Attribute.Constant(syms.byteType, poolReader.getConstant(nextChar()));
1896         case 'C':
1897             return new Attribute.Constant(syms.charType, poolReader.getConstant(nextChar()));
1898         case 'D':
1899             return new Attribute.Constant(syms.doubleType, poolReader.getConstant(nextChar()));
1900         case 'F':
1901             return new Attribute.Constant(syms.floatType, poolReader.getConstant(nextChar()));
1902         case 'I':
1903             return new Attribute.Constant(syms.intType, poolReader.getConstant(nextChar()));
1904         case 'J':
1905             return new Attribute.Constant(syms.longType, poolReader.getConstant(nextChar()));
1906         case 'S':
1907             return new Attribute.Constant(syms.shortType, poolReader.getConstant(nextChar()));
1908         case 'Z':
1909             return new Attribute.Constant(syms.booleanType, poolReader.getConstant(nextChar()));
1910         case 's':
1911             return new Attribute.Constant(syms.stringType, poolReader.getName(nextChar()).toString());
1912         case 'e':
1913             return new EnumAttributeProxy(readTypeToProxy(nextChar()), poolReader.getName(nextChar()));
1914         case 'c':
1915             return new ClassAttributeProxy(readTypeOrClassSymbol(nextChar()));
1916         case '[': {
1917             int n = nextChar();
1918             ListBuffer<Attribute> l = new ListBuffer<>();
1919             for (int i=0; i<n; i++)
1920                 l.append(readAttributeValue());
1921             return new ArrayAttributeProxy(l.toList());
1922         }
1923         case '@':
1924             return readCompoundAnnotation();
1925         default:
1926             throw new AssertionError("unknown annotation tag '" + c + "'");
1927         }
1928     }
1929 
1930     interface ProxyVisitor extends Attribute.Visitor {
1931         void visitEnumAttributeProxy(EnumAttributeProxy proxy);
1932         void visitClassAttributeProxy(ClassAttributeProxy proxy);
1933         void visitArrayAttributeProxy(ArrayAttributeProxy proxy);
1934         void visitCompoundAnnotationProxy(CompoundAnnotationProxy proxy);
1935     }
1936 
1937     static class EnumAttributeProxy extends Attribute {
1938         Type enumType;
1939         Name enumerator;
1940         public EnumAttributeProxy(Type enumType, Name enumerator) {
1941             super(null);
1942             this.enumType = enumType;
1943             this.enumerator = enumerator;
1944         }
1945         public void accept(Visitor v) { ((ProxyVisitor)v).visitEnumAttributeProxy(this); }
1946         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1947         public String toString() {
1948             return "/*proxy enum*/" + enumType + "." + enumerator;
1949         }
1950     }
1951 
1952     static class ClassAttributeProxy extends Attribute {
1953         Type classType;
1954         public ClassAttributeProxy(Type classType) {
1955             super(null);
1956             this.classType = classType;
1957         }
1958         public void accept(Visitor v) { ((ProxyVisitor)v).visitClassAttributeProxy(this); }
1959         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1960         public String toString() {
1961             return "/*proxy class*/" + classType + ".class";
1962         }
1963     }
1964 
1965     static class ArrayAttributeProxy extends Attribute {
1966         List<Attribute> values;
1967         ArrayAttributeProxy(List<Attribute> values) {
1968             super(null);
1969             this.values = values;
1970         }
1971         public void accept(Visitor v) { ((ProxyVisitor)v).visitArrayAttributeProxy(this); }
1972         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1973         public String toString() {
1974             return "{" + values + "}";
1975         }
1976     }
1977 
1978     /** A temporary proxy representing a compound attribute.
1979      */
1980     static class CompoundAnnotationProxy extends Attribute {
1981         final List<Pair<Name,Attribute>> values;
1982         public CompoundAnnotationProxy(Type type,
1983                                       List<Pair<Name,Attribute>> values) {
1984             super(type);
1985             this.values = values;
1986         }
1987         public void accept(Visitor v) { ((ProxyVisitor)v).visitCompoundAnnotationProxy(this); }
1988         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1989         public String toString() {
1990             StringBuilder buf = new StringBuilder();
1991             buf.append("@");
1992             buf.append(type.tsym.getQualifiedName());
1993             buf.append("/*proxy*/{");
1994             boolean first = true;
1995             for (List<Pair<Name,Attribute>> v = values;
1996                  v.nonEmpty(); v = v.tail) {
1997                 Pair<Name,Attribute> value = v.head;
1998                 if (!first) buf.append(",");
1999                 first = false;
2000                 buf.append(value.fst);
2001                 buf.append("=");
2002                 buf.append(value.snd);
2003             }
2004             buf.append("}");
2005             return buf.toString();
2006         }
2007     }
2008 
2009     /** A temporary proxy representing a type annotation.
2010      */
2011     static class TypeAnnotationProxy {
2012         final CompoundAnnotationProxy compound;
2013         final TypeAnnotationPosition position;
2014         public TypeAnnotationProxy(CompoundAnnotationProxy compound,
2015                 TypeAnnotationPosition position) {
2016             this.compound = compound;
2017             this.position = position;
2018         }
2019     }
2020 
2021     class AnnotationDeproxy implements ProxyVisitor {
2022         private ClassSymbol requestingOwner;
2023 
2024         AnnotationDeproxy(ClassSymbol owner) {
2025             this.requestingOwner = owner;
2026         }
2027 
2028         List<Attribute.Compound> deproxyCompoundList(List<CompoundAnnotationProxy> pl) {
2029             // also must fill in types!!!!
2030             ListBuffer<Attribute.Compound> buf = new ListBuffer<>();
2031             for (List<CompoundAnnotationProxy> l = pl; l.nonEmpty(); l=l.tail) {
2032                 buf.append(deproxyCompound(l.head));
2033             }
2034             return buf.toList();
2035         }
2036 
2037         Attribute.Compound deproxyCompound(CompoundAnnotationProxy a) {
2038             Type annotationType = resolvePossibleProxyType(a.type);
2039             ListBuffer<Pair<Symbol.MethodSymbol,Attribute>> buf = new ListBuffer<>();
2040             for (List<Pair<Name,Attribute>> l = a.values;
2041                  l.nonEmpty();
2042                  l = l.tail) {
2043                 MethodSymbol meth = findAccessMethod(annotationType, l.head.fst);
2044                 buf.append(new Pair<>(meth, deproxy(meth.type.getReturnType(), l.head.snd)));
2045             }
2046             return new Attribute.Compound(annotationType, buf.toList());
2047         }
2048 
2049         MethodSymbol findAccessMethod(Type container, Name name) {
2050             CompletionFailure failure = null;
2051             try {
2052                 for (Symbol sym : container.tsym.members().getSymbolsByName(name)) {
2053                     if (sym.kind == MTH && sym.type.getParameterTypes().length() == 0)
2054                         return (MethodSymbol) sym;
2055                 }
2056             } catch (CompletionFailure ex) {
2057                 failure = ex;
2058             }
2059             // The method wasn't found: emit a warning and recover
2060             JavaFileObject prevSource = log.useSource(requestingOwner.classfile);
2061             try {
2062                 if (lintClassfile) {
2063                     if (failure == null) {
2064                         log.warning(Warnings.AnnotationMethodNotFound(container, name));
2065                     } else {
2066                         log.warning(Warnings.AnnotationMethodNotFoundReason(container,
2067                                                                             name,
2068                                                                             failure.getDetailValue()));//diagnostic, if present
2069                     }
2070                 }
2071             } finally {
2072                 log.useSource(prevSource);
2073             }
2074             // Construct a new method type and symbol.  Use bottom
2075             // type (typeof null) as return type because this type is
2076             // a subtype of all reference types and can be converted
2077             // to primitive types by unboxing.
2078             MethodType mt = new MethodType(List.nil(),
2079                                            syms.botType,
2080                                            List.nil(),
2081                                            syms.methodClass);
2082             return new MethodSymbol(PUBLIC | ABSTRACT, name, mt, container.tsym);
2083         }
2084 
2085         Attribute result;
2086         Type type;
2087         Attribute deproxy(Type t, Attribute a) {
2088             Type oldType = type;
2089             try {
2090                 type = t;
2091                 a.accept(this);
2092                 return result;
2093             } finally {
2094                 type = oldType;
2095             }
2096         }
2097 
2098         // implement Attribute.Visitor below
2099 
2100         public void visitConstant(Attribute.Constant value) {
2101             // assert value.type == type;
2102             result = value;
2103         }
2104 
2105         public void visitClass(Attribute.Class clazz) {
2106             result = clazz;
2107         }
2108 
2109         public void visitEnum(Attribute.Enum e) {
2110             throw new AssertionError(); // shouldn't happen
2111         }
2112 
2113         public void visitCompound(Attribute.Compound compound) {
2114             throw new AssertionError(); // shouldn't happen
2115         }
2116 
2117         public void visitArray(Attribute.Array array) {
2118             throw new AssertionError(); // shouldn't happen
2119         }
2120 
2121         public void visitError(Attribute.Error e) {
2122             throw new AssertionError(); // shouldn't happen
2123         }
2124 
2125         public void visitEnumAttributeProxy(EnumAttributeProxy proxy) {
2126             // type.tsym.flatName() should == proxy.enumFlatName
2127             Type enumType = resolvePossibleProxyType(proxy.enumType);
2128             TypeSymbol enumTypeSym = enumType.tsym;
2129             VarSymbol enumerator = null;
2130             CompletionFailure failure = null;
2131             try {
2132                 for (Symbol sym : enumTypeSym.members().getSymbolsByName(proxy.enumerator)) {
2133                     if (sym.kind == VAR) {
2134                         enumerator = (VarSymbol)sym;
2135                         break;
2136                     }
2137                 }
2138             }
2139             catch (CompletionFailure ex) {
2140                 failure = ex;
2141             }
2142             if (enumerator == null) {
2143                 if (failure != null) {
2144                     log.warning(Warnings.UnknownEnumConstantReason(currentClassFile,
2145                                                                    enumTypeSym,
2146                                                                    proxy.enumerator,
2147                                                                    failure.getDiagnostic()));
2148                 } else {
2149                     log.warning(Warnings.UnknownEnumConstant(currentClassFile,
2150                                                              enumTypeSym,
2151                                                              proxy.enumerator));
2152                 }
2153                 result = new Attribute.Enum(enumTypeSym.type,
2154                         new VarSymbol(0, proxy.enumerator, syms.botType, enumTypeSym));
2155             } else {
2156                 result = new Attribute.Enum(enumTypeSym.type, enumerator);
2157             }
2158         }
2159 
2160         @Override
2161         public void visitClassAttributeProxy(ClassAttributeProxy proxy) {
2162             Type classType = resolvePossibleProxyType(proxy.classType);
2163             result = new Attribute.Class(types, classType);
2164         }
2165 
2166         public void visitArrayAttributeProxy(ArrayAttributeProxy proxy) {
2167             int length = proxy.values.length();
2168             Attribute[] ats = new Attribute[length];
2169             Type elemtype = types.elemtype(type);
2170             int i = 0;
2171             for (List<Attribute> p = proxy.values; p.nonEmpty(); p = p.tail) {
2172                 ats[i++] = deproxy(elemtype, p.head);
2173             }
2174             result = new Attribute.Array(type, ats);
2175         }
2176 
2177         public void visitCompoundAnnotationProxy(CompoundAnnotationProxy proxy) {
2178             result = deproxyCompound(proxy);
2179         }
2180 
2181         Type resolvePossibleProxyType(Type t) {
2182             if (t instanceof ProxyType proxyType) {
2183                 Assert.check(requestingOwner.owner.kind == MDL);
2184                 ModuleSymbol prevCurrentModule = currentModule;
2185                 currentModule = (ModuleSymbol) requestingOwner.owner;
2186                 try {
2187                     return proxyType.resolve();
2188                 } finally {
2189                     currentModule = prevCurrentModule;
2190                 }
2191             } else {
2192                 return t;
2193             }
2194         }
2195     }
2196 
2197     class AnnotationDefaultCompleter extends AnnotationDeproxy implements Runnable {
2198         final MethodSymbol sym;
2199         final Attribute value;
2200         final JavaFileObject classFile = currentClassFile;
2201 
2202         AnnotationDefaultCompleter(MethodSymbol sym, Attribute value) {
2203             super(currentOwner.kind == MTH
2204                     ? currentOwner.enclClass() : (ClassSymbol)currentOwner);
2205             this.sym = sym;
2206             this.value = value;
2207         }
2208 
2209         @Override
2210         public void run() {
2211             JavaFileObject previousClassFile = currentClassFile;
2212             try {
2213                 // Reset the interim value set earlier in
2214                 // attachAnnotationDefault().
2215                 sym.defaultValue = null;
2216                 currentClassFile = classFile;
2217                 sym.defaultValue = deproxy(sym.type.getReturnType(), value);
2218             } finally {
2219                 currentClassFile = previousClassFile;
2220             }
2221         }
2222 
2223         @Override
2224         public String toString() {
2225             return " ClassReader store default for " + sym.owner + "." + sym + " is " + value;
2226         }
2227     }
2228 
2229     class AnnotationCompleter extends AnnotationDeproxy implements Runnable {
2230         final Symbol sym;
2231         final List<CompoundAnnotationProxy> l;
2232         final JavaFileObject classFile;
2233 
2234         AnnotationCompleter(Symbol sym, List<CompoundAnnotationProxy> l) {
2235             super(currentOwner.kind == MTH
2236                     ? currentOwner.enclClass() : (ClassSymbol)currentOwner);
2237             if (sym.kind == TYP && sym.owner.kind == MDL) {
2238                 this.sym = sym.owner;
2239             } else {
2240                 this.sym = sym;
2241             }
2242             this.l = l;
2243             this.classFile = currentClassFile;
2244         }
2245 
2246         @Override
2247         public void run() {
2248             JavaFileObject previousClassFile = currentClassFile;
2249             try {
2250                 currentClassFile = classFile;
2251                 List<Attribute.Compound> newList = deproxyCompoundList(l);
2252                 for (Attribute.Compound attr : newList) {
2253                     if (attr.type.tsym == syms.deprecatedType.tsym) {
2254                         sym.flags_field |= (DEPRECATED | DEPRECATED_ANNOTATION);
2255                         Attribute forRemoval = attr.member(names.forRemoval);
2256                         if (forRemoval instanceof Attribute.Constant constant) {
2257                             if (constant.type == syms.booleanType && ((Integer) constant.value) != 0) {
2258                                 sym.flags_field |= DEPRECATED_REMOVAL;
2259                             }
2260                         }
2261                     }
2262                 }
2263                 if (sym.annotationsPendingCompletion()) {
2264                     sym.setDeclarationAttributes(newList);
2265                 } else {
2266                     sym.appendAttributes(newList);
2267                 }
2268             } finally {
2269                 currentClassFile = previousClassFile;
2270             }
2271         }
2272 
2273         @Override
2274         public String toString() {
2275             return " ClassReader annotate " + sym.owner + "." + sym + " with " + l;
2276         }
2277     }
2278 
2279     class TypeAnnotationCompleter extends AnnotationCompleter {
2280 
2281         List<TypeAnnotationProxy> proxies;
2282 
2283         TypeAnnotationCompleter(Symbol sym,
2284                 List<TypeAnnotationProxy> proxies) {
2285             super(sym, List.nil());
2286             this.proxies = proxies;
2287         }
2288 
2289         List<Attribute.TypeCompound> deproxyTypeCompoundList(List<TypeAnnotationProxy> proxies) {
2290             ListBuffer<Attribute.TypeCompound> buf = new ListBuffer<>();
2291             for (TypeAnnotationProxy proxy: proxies) {
2292                 Attribute.Compound compound = deproxyCompound(proxy.compound);
2293                 Attribute.TypeCompound typeCompound = new Attribute.TypeCompound(compound, proxy.position);
2294                 buf.add(typeCompound);
2295             }
2296             return buf.toList();
2297         }
2298 
2299         @Override
2300         public void run() {
2301             JavaFileObject previousClassFile = currentClassFile;
2302             try {
2303                 currentClassFile = classFile;
2304                 List<Attribute.TypeCompound> newList = deproxyTypeCompoundList(proxies);
2305                 sym.setTypeAttributes(newList.prependList(sym.getRawTypeAttributes()));
2306             } finally {
2307                 currentClassFile = previousClassFile;
2308             }
2309         }
2310     }
2311 
2312 
2313 /************************************************************************
2314  * Reading Symbols
2315  ***********************************************************************/
2316 
2317     /** Read a field.
2318      */
2319     VarSymbol readField() {
2320         char rawFlags = nextChar();
2321         long flags = adjustFieldFlags(rawFlags);
2322         Name name = poolReader.getName(nextChar());
2323         Type type = poolReader.getType(nextChar());
2324         VarSymbol v = new VarSymbol(flags, name, type, currentOwner);
2325         readMemberAttrs(v);
2326         if (Integer.bitCount(rawFlags & (PUBLIC | PRIVATE | PROTECTED)) > 1 ||
2327             Integer.bitCount(rawFlags & (FINAL | VOLATILE)) > 1)
2328             throw badClassFile("illegal.flag.combo", Flags.toString((long)rawFlags), "field", v);
2329         return v;
2330     }
2331 
2332     /** Read a method.
2333      */
2334     MethodSymbol readMethod() {
2335         char rawFlags = nextChar();
2336         long flags = adjustMethodFlags(rawFlags);
2337         Name name = poolReader.getName(nextChar());
2338         Type type = poolReader.getType(nextChar());
2339         if (currentOwner.isInterface() &&
2340                 (flags & ABSTRACT) == 0 && !name.equals(names.clinit)) {
2341             if (majorVersion > Version.V52.major ||
2342                     (majorVersion == Version.V52.major && minorVersion >= Version.V52.minor)) {
2343                 if ((flags & (STATIC | PRIVATE)) == 0) {
2344                     currentOwner.flags_field |= DEFAULT;
2345                     flags |= DEFAULT | ABSTRACT;
2346                 }
2347             } else {
2348                 //protect against ill-formed classfiles
2349                 throw badClassFile((flags & STATIC) == 0 ? "invalid.default.interface" : "invalid.static.interface",
2350                                    Integer.toString(majorVersion),
2351                                    Integer.toString(minorVersion));
2352             }
2353         }
2354         if (names.isInitOrVNew(name) && ((flags & STATIC) != 0)) {
2355             flags &= ~STATIC;
2356             type = new MethodType(type.getParameterTypes(),
2357                     syms.voidType,
2358                     type.getThrownTypes(),
2359                     syms.methodClass);
2360         }
2361         validateMethodType(name, type);
2362         if (names.isInitOrVNew(name) && currentOwner.hasOuterInstance()) {
2363             // Sometimes anonymous classes don't have an outer
2364             // instance, however, there is no reliable way to tell so
2365             // we never strip this$n
2366             // ditto for local classes. Local classes that have an enclosing method set
2367             // won't pass the "hasOuterInstance" check above, but those that don't have an
2368             // enclosing method (i.e. from initializers) will pass that check.
2369             boolean local = !currentOwner.owner.members().includes(currentOwner, LookupKind.NON_RECURSIVE);
2370             if (!currentOwner.name.isEmpty() && !local)
2371                 type = new MethodType(adjustMethodParams(flags, type.getParameterTypes()),
2372                                       type.getReturnType(),
2373                                       type.getThrownTypes(),
2374                                       syms.methodClass);
2375         }
2376         MethodSymbol m = new MethodSymbol(flags, name, type, currentOwner);
2377         if (types.isSignaturePolymorphic(m)) {
2378             m.flags_field |= SIGNATURE_POLYMORPHIC;
2379         }
2380         if (saveParameterNames)
2381             initParameterNames(m);
2382         Symbol prevOwner = currentOwner;
2383         currentOwner = m;
2384         try {
2385             readMemberAttrs(m);
2386         } finally {
2387             currentOwner = prevOwner;
2388         }
2389         validateMethodType(name, m.type);
2390         setParameters(m, type);
2391 
2392         if (Integer.bitCount(rawFlags & (PUBLIC | PRIVATE | PROTECTED)) > 1)
2393             throw badClassFile("illegal.flag.combo", Flags.toString((long)rawFlags), "method", m);
2394         if ((flags & VARARGS) != 0) {
2395             final Type last = type.getParameterTypes().last();
2396             if (last == null || !last.hasTag(ARRAY)) {
2397                 m.flags_field &= ~VARARGS;
2398                 throw badClassFile("malformed.vararg.method", m);
2399             }
2400         }
2401 
2402         return m;
2403     }
2404 
2405     void validateMethodType(Name name, Type t) {
2406         if ((!t.hasTag(TypeTag.METHOD) && !t.hasTag(TypeTag.FORALL)) ||
2407             ((name == names.init || name == names.vnew) && !t.getReturnType().hasTag(TypeTag.VOID))) {
2408             throw badClassFile("method.descriptor.invalid", name);
2409         }
2410     }
2411 
2412     private List<Type> adjustMethodParams(long flags, List<Type> args) {
2413         if (args.isEmpty()) {
2414             return args;
2415         }
2416         boolean isVarargs = (flags & VARARGS) != 0;
2417         if (isVarargs) {
2418             Type varargsElem = args.last();
2419             ListBuffer<Type> adjustedArgs = new ListBuffer<>();
2420             for (Type t : args) {
2421                 adjustedArgs.append(t != varargsElem ?
2422                     t :
2423                     ((ArrayType)t).makeVarargs());
2424             }
2425             args = adjustedArgs.toList();
2426         }
2427         return args.tail;
2428     }
2429 
2430     /**
2431      * Init the parameter names array.
2432      * Parameter names are currently inferred from the names in the
2433      * LocalVariableTable attributes of a Code attribute.
2434      * (Note: this means parameter names are currently not available for
2435      * methods without a Code attribute.)
2436      * This method initializes an array in which to store the name indexes
2437      * of parameter names found in LocalVariableTable attributes. It is
2438      * slightly supersized to allow for additional slots with a start_pc of 0.
2439      */
2440     void initParameterNames(MethodSymbol sym) {
2441         // make allowance for synthetic parameters.
2442         final int excessSlots = 4;
2443         int expectedParameterSlots =
2444                 Code.width(sym.type.getParameterTypes()) + excessSlots;
2445         if (parameterNameIndicesLvt == null
2446                 || parameterNameIndicesLvt.length < expectedParameterSlots) {
2447             parameterNameIndicesLvt = new int[expectedParameterSlots];
2448         } else
2449             Arrays.fill(parameterNameIndicesLvt, 0);
2450     }
2451 
2452     /**
2453      * Set the parameters for a method symbol, including any names and
2454      * annotations that were read.
2455      *
2456      * <p>The type of the symbol may have changed while reading the
2457      * method attributes (see the Signature attribute). This may be
2458      * because of generic information or because anonymous synthetic
2459      * parameters were added.   The original type (as read from the
2460      * method descriptor) is used to help guess the existence of
2461      * anonymous synthetic parameters.
2462      */
2463     void setParameters(MethodSymbol sym, Type jvmType) {
2464         int firstParamLvt = ((sym.flags() & STATIC) == 0) ? 1 : 0;
2465         // the code in readMethod may have skipped the first
2466         // parameter when setting up the MethodType. If so, we
2467         // make a corresponding allowance here for the position of
2468         // the first parameter.  Note that this assumes the
2469         // skipped parameter has a width of 1 -- i.e. it is not
2470         // a double width type (long or double.)
2471         if (names.isInitOrVNew(sym.name) && currentOwner.hasOuterInstance()) {
2472             // Sometimes anonymous classes don't have an outer
2473             // instance, however, there is no reliable way to tell so
2474             // we never strip this$n
2475             if (!currentOwner.name.isEmpty())
2476                 firstParamLvt += 1;
2477         }
2478 
2479         if (sym.type != jvmType) {
2480             // reading the method attributes has caused the
2481             // symbol's type to be changed. (i.e. the Signature
2482             // attribute.)  This may happen if there are hidden
2483             // (synthetic) parameters in the descriptor, but not
2484             // in the Signature.  The position of these hidden
2485             // parameters is unspecified; for now, assume they are
2486             // at the beginning, and so skip over them. The
2487             // primary case for this is two hidden parameters
2488             // passed into Enum constructors.
2489             int skip = Code.width(jvmType.getParameterTypes())
2490                     - Code.width(sym.type.getParameterTypes());
2491             firstParamLvt += skip;
2492         }
2493         Set<Name> paramNames = new HashSet<>();
2494         ListBuffer<VarSymbol> params = new ListBuffer<>();
2495         // we maintain two index pointers, one for the LocalVariableTable attribute
2496         // and the other for the MethodParameters attribute.
2497         // This is needed as the MethodParameters attribute may contain
2498         // name_index = 0 in which case we want to fall back to the LocalVariableTable.
2499         // In such case, we still want to read the flags from the MethodParameters with that index.
2500         int nameIndexLvt = firstParamLvt;
2501         int nameIndexMp = 0;
2502         int annotationIndex = 0;
2503         for (Type t: sym.type.getParameterTypes()) {
2504             VarSymbol param = parameter(nameIndexMp, nameIndexLvt, t, sym, paramNames);
2505             params.append(param);
2506             if (parameterAnnotations != null) {
2507                 ParameterAnnotations annotations = parameterAnnotations[annotationIndex];
2508                 if (annotations != null && annotations.proxies != null
2509                         && !annotations.proxies.isEmpty()) {
2510                     annotate.normal(new AnnotationCompleter(param, annotations.proxies));
2511                 }
2512             }
2513             nameIndexLvt += Code.width(t);
2514             nameIndexMp++;
2515             annotationIndex++;
2516         }
2517         if (parameterAnnotations != null && parameterAnnotations.length != annotationIndex) {
2518             throw badClassFile("bad.runtime.invisible.param.annotations", sym);
2519         }
2520         Assert.checkNull(sym.params);
2521         sym.params = params.toList();
2522         parameterAnnotations = null;
2523         parameterNameIndicesLvt = null;
2524         parameterNameIndicesMp = null;
2525         parameterAccessFlags = null;
2526     }
2527 
2528     /**
2529      * Creates the parameter at the position {@code mpIndex} in the parameter list of the owning method.
2530      * Flags are optionally read from the MethodParameters attribute.
2531      * Names are optionally read from the MethodParameters attribute. If the constant pool index
2532      * of the name is 0, then the name is optionally read from the LocalVariableTable attribute.
2533      * @param mpIndex the index of the parameter in the MethodParameters attribute
2534      * @param lvtIndex the index of the parameter in the LocalVariableTable attribute
2535      */
2536     private VarSymbol parameter(int mpIndex, int lvtIndex, Type t, MethodSymbol owner, Set<Name> exclude) {
2537         long flags = PARAMETER;
2538         Name argName;
2539         if (parameterAccessFlags != null && mpIndex < parameterAccessFlags.length
2540                 && parameterAccessFlags[mpIndex] != 0) {
2541             flags |= parameterAccessFlags[mpIndex];
2542         }
2543         if (parameterNameIndicesMp != null
2544                 // if name_index is 0, then we might still get a name from the LocalVariableTable
2545                 && parameterNameIndicesMp[mpIndex] != 0) {
2546             argName = optPoolEntry(parameterNameIndicesMp[mpIndex], poolReader::getName, names.empty);
2547             flags |= NAME_FILLED;
2548         } else if (parameterNameIndicesLvt != null && lvtIndex < parameterNameIndicesLvt.length
2549                 && parameterNameIndicesLvt[lvtIndex] != 0) {
2550             argName = optPoolEntry(parameterNameIndicesLvt[lvtIndex], poolReader::getName, names.empty);
2551             flags |= NAME_FILLED;
2552         } else {
2553             String prefix = "arg";
2554             while (true) {
2555                 argName = names.fromString(prefix + exclude.size());
2556                 if (!exclude.contains(argName))
2557                     break;
2558                 prefix += "$";
2559             }
2560         }
2561         exclude.add(argName);
2562         return new ParamSymbol(flags, argName, t, owner);
2563     }
2564 
2565     /**
2566      * skip n bytes
2567      */
2568     void skipBytes(int n) {
2569         bp = bp + n;
2570     }
2571 
2572     /** Skip a field or method
2573      */
2574     void skipMember() {
2575         bp = bp + 6;
2576         char ac = nextChar();
2577         for (int i = 0; i < ac; i++) {
2578             bp = bp + 2;
2579             int attrLen = nextInt();
2580             bp = bp + attrLen;
2581         }
2582     }
2583 
2584     void skipInnerClasses() {
2585         int n = nextChar();
2586         for (int i = 0; i < n; i++) {
2587             nextChar();
2588             nextChar();
2589             nextChar();
2590             nextChar();
2591         }
2592     }
2593 
2594     /** Enter type variables of this classtype and all enclosing ones in
2595      *  `typevars'.
2596      */
2597     protected void enterTypevars(Symbol sym, Type t) {
2598         if (t.getEnclosingType() != null) {
2599             if (!t.getEnclosingType().hasTag(TypeTag.NONE)) {
2600                 enterTypevars(sym.owner, t.getEnclosingType());
2601             }
2602         } else if (sym.kind == MTH && !sym.isStatic()) {
2603             enterTypevars(sym.owner, sym.owner.type);
2604         }
2605         for (List<Type> xs = t.getTypeArguments(); xs.nonEmpty(); xs = xs.tail) {
2606             typevars.enter(xs.head.tsym);
2607         }
2608     }
2609 
2610     protected ClassSymbol enterClass(Name name) {
2611         return syms.enterClass(currentModule, name);
2612     }
2613 
2614     protected ClassSymbol enterClass(Name name, TypeSymbol owner) {
2615         return syms.enterClass(currentModule, name, owner);
2616     }
2617 
2618     /** Read contents of a given class symbol `c'. Both external and internal
2619      *  versions of an inner class are read.
2620      */
2621     void readClass(ClassSymbol c) {
2622         ClassType ct = (ClassType)c.type;
2623 
2624         // allocate scope for members
2625         c.members_field = WriteableScope.create(c);
2626 
2627         // prepare type variable table
2628         typevars = typevars.dup(currentOwner);
2629         if (ct.getEnclosingType().hasTag(CLASS))
2630             enterTypevars(c.owner, ct.getEnclosingType());
2631 
2632         // read flags, or skip if this is an inner class
2633         long f = nextChar();
2634         long flags = adjustClassFlags(f);
2635         if (c == syms.objectType.tsym) {
2636             flags &= ~IDENTITY_TYPE; // jlO lacks identity even while being a concrete class.
2637         }
2638         if ((flags & PRIMITIVE_CLASS) != 0) {
2639             if (!allowPrimitiveClasses || (flags & (FINAL | PRIMITIVE_CLASS | IDENTITY_TYPE)) != (FINAL | PRIMITIVE_CLASS)) {
2640                 throw badClassFile("bad.access.flags", Flags.toString(flags));
2641             }
2642         }
2643         if ((flags & MODULE) == 0) {
2644             if (c.owner.kind == PCK || c.owner.kind == ERR) c.flags_field = flags;
2645             // read own class name and check that it matches
2646             currentModule = c.packge().modle;
2647             ClassSymbol self = poolReader.getClass(nextChar());
2648             if (c != self) {
2649                 throw badClassFile("class.file.wrong.class",
2650                                    self.flatname);
2651             }
2652         } else {
2653             if (majorVersion < Version.V53.major) {
2654                 throw badClassFile("anachronistic.module.info",
2655                         Integer.toString(majorVersion),
2656                         Integer.toString(minorVersion));
2657             }
2658             c.flags_field = flags;
2659             if (c.owner.kind != MDL) {
2660                 throw badClassFile("module.info.definition.expected");
2661             }
2662             currentModule = (ModuleSymbol) c.owner;
2663             int this_class = nextChar();
2664             // temp, no check on this_class
2665         }
2666 
2667         // class attributes must be read before class
2668         // skip ahead to read class attributes
2669         int startbp = bp;
2670         nextChar();
2671         char interfaceCount = nextChar();
2672         bp += interfaceCount * 2;
2673         char fieldCount = nextChar();
2674         for (int i = 0; i < fieldCount; i++) skipMember();
2675         char methodCount = nextChar();
2676         for (int i = 0; i < methodCount; i++) skipMember();
2677         readClassAttrs(c);
2678 
2679         if (c.permitted != null && !c.permitted.isEmpty()) {
2680             c.flags_field |= SEALED;
2681         }
2682 
2683         // reset and read rest of classinfo
2684         bp = startbp;
2685         int n = nextChar();
2686         if ((flags & MODULE) != 0 && n > 0) {
2687             throw badClassFile("module.info.invalid.super.class");
2688         }
2689         if (ct.supertype_field == null)
2690             ct.supertype_field =
2691                     optPoolEntry(n, idx -> poolReader.getClass(idx).erasure(types), Type.noType);
2692         n = nextChar();
2693         List<Type> is = List.nil();
2694         for (int i = 0; i < n; i++) {
2695             Type _inter = poolReader.getClass(nextChar()).erasure(types);
2696             is = is.prepend(_inter);
2697         }
2698         if (ct.interfaces_field == null)
2699             ct.interfaces_field = is.reverse();
2700 
2701         Assert.check(fieldCount == nextChar());
2702         for (int i = 0; i < fieldCount; i++) enterMember(c, readField());
2703         Assert.check(methodCount == nextChar());
2704         for (int i = 0; i < methodCount; i++) enterMember(c, readMethod());
2705         if (c.isRecord()) {
2706             for (RecordComponent rc: c.getRecordComponents()) {
2707                 rc.accessor = lookupMethod(c, rc.name, List.nil());
2708             }
2709         }
2710         typevars = typevars.leave();
2711     }
2712 
2713     private MethodSymbol lookupMethod(TypeSymbol tsym, Name name, List<Type> argtypes) {
2714         for (Symbol s : tsym.members().getSymbolsByName(name, s -> s.kind == MTH)) {
2715             if (types.isSameTypes(s.type.getParameterTypes(), argtypes)) {
2716                 return (MethodSymbol) s;
2717             }
2718         }
2719         return null;
2720     }
2721 
2722     /** Read inner class info. For each inner/outer pair allocate a
2723      *  member class.
2724      */
2725     void readInnerClasses(ClassSymbol c) {
2726         int n = nextChar();
2727         for (int i = 0; i < n; i++) {
2728             nextChar(); // skip inner class symbol
2729             int outerIdx = nextChar();
2730             int nameIdx = nextChar();
2731             ClassSymbol outer = optPoolEntry(outerIdx, poolReader::getClass, null);
2732             Name name = optPoolEntry(nameIdx, poolReader::getName, names.empty);
2733             if (name == null) name = names.empty;
2734             long flags = adjustClassFlags(nextChar());
2735             if (outer != null) { // we have a member class
2736                 if (name == names.empty)
2737                     name = names.one;
2738                 ClassSymbol member = enterClass(name, outer);
2739                 if ((flags & STATIC) == 0) {
2740                     ((ClassType)member.type).setEnclosingType(outer.type);
2741                     if (member.erasure_field != null)
2742                         ((ClassType)member.erasure_field).setEnclosingType(types.erasure(outer.type));
2743                 }
2744                 if (c == outer && member.owner == c) {
2745                     member.flags_field = flags;
2746                     enterMember(c, member);
2747                 }
2748             }
2749         }
2750     }
2751 
2752     /** Read a class definition from the bytes in buf.
2753      */
2754     private void readClassBuffer(ClassSymbol c) throws IOException {
2755         int magic = nextInt();
2756         if (magic != JAVA_MAGIC)
2757             throw badClassFile("illegal.start.of.class.file");
2758 
2759         minorVersion = nextChar();
2760         majorVersion = nextChar();
2761         int maxMajor = Version.MAX().major;
2762         int maxMinor = Version.MAX().minor;
2763         boolean previewClassFile =
2764                 minorVersion == ClassFile.PREVIEW_MINOR_VERSION;
2765         if (majorVersion > maxMajor ||
2766             majorVersion * 1000 + minorVersion <
2767             Version.MIN().major * 1000 + Version.MIN().minor) {
2768             if (majorVersion == (maxMajor + 1) && !previewClassFile)
2769                 log.warning(Warnings.BigMajorVersion(currentClassFile,
2770                                                      majorVersion,
2771                                                      maxMajor));
2772             else
2773                 throw badClassFile("wrong.version",
2774                                    Integer.toString(majorVersion),
2775                                    Integer.toString(minorVersion),
2776                                    Integer.toString(maxMajor),
2777                                    Integer.toString(maxMinor));
2778         }
2779         utf8validation = majorVersion < V48.major ? Convert.Validation.PREJDK14 : Convert.Validation.STRICT;
2780 
2781         if (previewClassFile) {
2782             if (!preview.isEnabled()) {
2783                 log.error(preview.disabledError(currentClassFile, majorVersion));
2784             } else {
2785                 preview.warnPreview(c.classfile, majorVersion);
2786             }
2787         }
2788 
2789         poolReader = new PoolReader(this, names, syms);
2790         bp = poolReader.readPool(buf, bp);
2791         if (signatureBuffer.length < bp) {
2792             int ns = Integer.highestOneBit(bp) << 1;
2793             signatureBuffer = new byte[ns];
2794         }
2795         readClass(c);
2796         if (previewClassFile) {
2797             if ((c.flags_field & SYNTHETIC) != 0 &&
2798                     c.owner.kind == PCK &&
2799                     (c.flags_field & AUXILIARY) == 0 &&
2800                     (c.flags_field & FINAL) != 0) {
2801                 c.flags_field |= UNNAMED_CLASS;
2802             }
2803         }
2804     }
2805 
2806     public void readClassFile(ClassSymbol c) {
2807         currentOwner = c;
2808         currentClassFile = c.classfile;
2809         warnedAttrs.clear();
2810         filling = true;
2811         target = null;
2812         repeatable = null;
2813         try {
2814             bp = 0;
2815             buf.reset();
2816             try (InputStream input = c.classfile.openInputStream()) {
2817                 buf.appendStream(input);
2818             }
2819             readClassBuffer(c);
2820             if (!missingTypeVariables.isEmpty() && !foundTypeVariables.isEmpty()) {
2821                 List<Type> missing = missingTypeVariables;
2822                 List<Type> found = foundTypeVariables;
2823                 missingTypeVariables = List.nil();
2824                 foundTypeVariables = List.nil();
2825                 interimUses = List.nil();
2826                 interimProvides = List.nil();
2827                 filling = false;
2828                 ClassType ct = (ClassType)currentOwner.type;
2829                 ct.supertype_field =
2830                     types.subst(ct.supertype_field, missing, found);
2831                 ct.interfaces_field =
2832                     types.subst(ct.interfaces_field, missing, found);
2833                 ct.typarams_field =
2834                     types.substBounds(ct.typarams_field, missing, found);
2835                 for (List<Type> types = ct.typarams_field; types.nonEmpty(); types = types.tail) {
2836                     types.head.tsym.type = types.head;
2837                 }
2838             } else if (missingTypeVariables.isEmpty() !=
2839                        foundTypeVariables.isEmpty()) {
2840                 Name name = missingTypeVariables.head.tsym.name;
2841                 throw badClassFile("undecl.type.var", name);
2842             }
2843 
2844             if ((c.flags_field & Flags.ANNOTATION) != 0) {
2845                 c.setAnnotationTypeMetadata(new AnnotationTypeMetadata(c, new CompleterDeproxy(c, target, repeatable)));
2846             } else {
2847                 c.setAnnotationTypeMetadata(AnnotationTypeMetadata.notAnAnnotationType());
2848             }
2849 
2850             if (c == currentModule.module_info) {
2851                 if (interimUses.nonEmpty() || interimProvides.nonEmpty()) {
2852                     Assert.check(currentModule.isCompleted());
2853                     currentModule.usesProvidesCompleter =
2854                             new UsesProvidesCompleter(currentModule, interimUses, interimProvides);
2855                 } else {
2856                     currentModule.uses = List.nil();
2857                     currentModule.provides = List.nil();
2858                 }
2859             }
2860         } catch (IOException | ClosedFileSystemException ex) {
2861             throw badClassFile("unable.to.access.file", ex.toString());
2862         } catch (ArrayIndexOutOfBoundsException ex) {
2863             throw badClassFile("bad.class.file", c.flatname);
2864         } finally {
2865             interimUses = List.nil();
2866             interimProvides = List.nil();
2867             missingTypeVariables = List.nil();
2868             foundTypeVariables = List.nil();
2869             filling = false;
2870         }
2871     }
2872 
2873     /** We can only read a single class file at a time; this
2874      *  flag keeps track of when we are currently reading a class
2875      *  file.
2876      */
2877     public boolean filling = false;
2878 
2879 /************************************************************************
2880  * Adjusting flags
2881  ***********************************************************************/
2882 
2883     long adjustFieldFlags(long flags) {
2884         return flags;
2885     }
2886 
2887     long adjustMethodFlags(long flags) {
2888         if ((flags & ACC_BRIDGE) != 0) {
2889             flags &= ~ACC_BRIDGE;
2890             flags |= BRIDGE;
2891         }
2892         if ((flags & ACC_VARARGS) != 0) {
2893             flags &= ~ACC_VARARGS;
2894             flags |= VARARGS;
2895         }
2896         return flags;
2897     }
2898 
2899     long adjustClassFlags(long flags) {
2900         if ((flags & (ABSTRACT | INTERFACE | ACC_VALUE | ACC_MODULE)) == 0) {
2901             flags |= ACC_IDENTITY;
2902         }
2903         if ((flags & ACC_MODULE) != 0) {
2904             flags &= ~ACC_MODULE;
2905             flags |= MODULE;
2906         }
2907         if ((flags & ACC_PRIMITIVE) != 0) {
2908             flags &= ~ACC_PRIMITIVE;
2909             if (allowPrimitiveClasses) {
2910                 flags |= PRIMITIVE_CLASS;
2911             }
2912         }
2913         if ((flags & ACC_VALUE) != 0) {
2914             flags &= ~ACC_VALUE;
2915             if (allowValueClasses) {
2916                 flags |= VALUE_CLASS;
2917             }
2918         }
2919         if ((flags & ACC_IDENTITY) != 0) {
2920             flags &= ~ACC_IDENTITY;
2921             flags |= IDENTITY_TYPE;
2922         }
2923         return flags;
2924     }
2925 
2926     /**
2927      * A subclass of JavaFileObject for the sourcefile attribute found in a classfile.
2928      * The attribute is only the last component of the original filename, so is unlikely
2929      * to be valid as is, so operations other than those to access the name throw
2930      * UnsupportedOperationException
2931      */
2932     private static class SourceFileObject implements JavaFileObject {
2933 
2934         /** The file's name.
2935          */
2936         private final Name name;
2937 
2938         public SourceFileObject(Name name) {
2939             this.name = name;
2940         }
2941 
2942         @Override @DefinedBy(Api.COMPILER)
2943         public URI toUri() {
2944             try {
2945                 return new URI(null, name.toString(), null);
2946             } catch (URISyntaxException e) {
2947                 throw new PathFileObject.CannotCreateUriError(name.toString(), e);
2948             }
2949         }
2950 
2951         @Override @DefinedBy(Api.COMPILER)
2952         public String getName() {
2953             return name.toString();
2954         }
2955 
2956         @Override @DefinedBy(Api.COMPILER)
2957         public JavaFileObject.Kind getKind() {
2958             return BaseFileManager.getKind(getName());
2959         }
2960 
2961         @Override @DefinedBy(Api.COMPILER)
2962         public InputStream openInputStream() {
2963             throw new UnsupportedOperationException();
2964         }
2965 
2966         @Override @DefinedBy(Api.COMPILER)
2967         public OutputStream openOutputStream() {
2968             throw new UnsupportedOperationException();
2969         }
2970 
2971         @Override @DefinedBy(Api.COMPILER)
2972         public CharBuffer getCharContent(boolean ignoreEncodingErrors) {
2973             throw new UnsupportedOperationException();
2974         }
2975 
2976         @Override @DefinedBy(Api.COMPILER)
2977         public Reader openReader(boolean ignoreEncodingErrors) {
2978             throw new UnsupportedOperationException();
2979         }
2980 
2981         @Override @DefinedBy(Api.COMPILER)
2982         public Writer openWriter() {
2983             throw new UnsupportedOperationException();
2984         }
2985 
2986         @Override @DefinedBy(Api.COMPILER)
2987         public long getLastModified() {
2988             throw new UnsupportedOperationException();
2989         }
2990 
2991         @Override @DefinedBy(Api.COMPILER)
2992         public boolean delete() {
2993             throw new UnsupportedOperationException();
2994         }
2995 
2996         @Override @DefinedBy(Api.COMPILER)
2997         public boolean isNameCompatible(String simpleName, JavaFileObject.Kind kind) {
2998             return true; // fail-safe mode
2999         }
3000 
3001         @Override @DefinedBy(Api.COMPILER)
3002         public NestingKind getNestingKind() {
3003             return null;
3004         }
3005 
3006         @Override @DefinedBy(Api.COMPILER)
3007         public Modifier getAccessLevel() {
3008             return null;
3009         }
3010 
3011         /**
3012          * Check if two file objects are equal.
3013          * SourceFileObjects are just placeholder objects for the value of a
3014          * SourceFile attribute, and do not directly represent specific files.
3015          * Two SourceFileObjects are equal if their names are equal.
3016          */
3017         @Override
3018         public boolean equals(Object other) {
3019             if (this == other)
3020                 return true;
3021             return (other instanceof SourceFileObject sourceFileObject)
3022                     && name.equals(sourceFileObject.name);
3023         }
3024 
3025         @Override
3026         public int hashCode() {
3027             return name.hashCode();
3028         }
3029     }
3030 
3031     private class CompleterDeproxy implements AnnotationTypeCompleter {
3032         ClassSymbol proxyOn;
3033         CompoundAnnotationProxy target;
3034         CompoundAnnotationProxy repeatable;
3035 
3036         public CompleterDeproxy(ClassSymbol c, CompoundAnnotationProxy target,
3037                 CompoundAnnotationProxy repeatable)
3038         {
3039             this.proxyOn = c;
3040             this.target = target;
3041             this.repeatable = repeatable;
3042         }
3043 
3044         @Override
3045         public void complete(ClassSymbol sym) {
3046             Assert.check(proxyOn == sym);
3047             Attribute.Compound theTarget = null, theRepeatable = null;
3048             AnnotationDeproxy deproxy;
3049 
3050             try {
3051                 if (target != null) {
3052                     deproxy = new AnnotationDeproxy(proxyOn);
3053                     theTarget = deproxy.deproxyCompound(target);
3054                 }
3055 
3056                 if (repeatable != null) {
3057                     deproxy = new AnnotationDeproxy(proxyOn);
3058                     theRepeatable = deproxy.deproxyCompound(repeatable);
3059                 }
3060             } catch (Exception e) {
3061                 throw new CompletionFailure(sym,
3062                                             () -> ClassReader.this.diagFactory.fragment(Fragments.ExceptionMessage(e.getMessage())),
3063                                             dcfh);
3064             }
3065 
3066             sym.getAnnotationTypeMetadata().setTarget(theTarget);
3067             sym.getAnnotationTypeMetadata().setRepeatable(theRepeatable);
3068         }
3069     }
3070 
3071     private class ProxyType extends Type {
3072 
3073         private final Name name;
3074 
3075         public ProxyType(int index) {
3076             super(syms.noSymbol, List.nil());
3077             this.name = poolReader.getName(index);
3078         }
3079 
3080         @Override
3081         public TypeTag getTag() {
3082             return TypeTag.NONE;
3083         }
3084 
3085         public Type resolve() {
3086             return name.map(ClassReader.this::sigToType);
3087         }
3088 
3089         @Override @DefinedBy(Api.LANGUAGE_MODEL)
3090         public String toString() {
3091             return "<ProxyType>";
3092         }
3093 
3094     }
3095 
3096     private static final class InterimUsesDirective {
3097         public final Name service;
3098 
3099         public InterimUsesDirective(Name service) {
3100             this.service = service;
3101         }
3102 
3103     }
3104 
3105     private static final class InterimProvidesDirective {
3106         public final Name service;
3107         public final List<Name> impls;
3108 
3109         public InterimProvidesDirective(Name service, List<Name> impls) {
3110             this.service = service;
3111             this.impls = impls;
3112         }
3113 
3114     }
3115 
3116     private final class UsesProvidesCompleter implements Completer {
3117         private final ModuleSymbol currentModule;
3118         private final List<InterimUsesDirective> interimUsesCopy;
3119         private final List<InterimProvidesDirective> interimProvidesCopy;
3120 
3121         public UsesProvidesCompleter(ModuleSymbol currentModule, List<InterimUsesDirective> interimUsesCopy, List<InterimProvidesDirective> interimProvidesCopy) {
3122             this.currentModule = currentModule;
3123             this.interimUsesCopy = interimUsesCopy;
3124             this.interimProvidesCopy = interimProvidesCopy;
3125         }
3126 
3127         @Override
3128         public void complete(Symbol sym) throws CompletionFailure {
3129             ListBuffer<Directive> directives = new ListBuffer<>();
3130             directives.addAll(currentModule.directives);
3131             ListBuffer<UsesDirective> uses = new ListBuffer<>();
3132             for (InterimUsesDirective interim : interimUsesCopy) {
3133                 UsesDirective d = new UsesDirective(syms.enterClass(currentModule, interim.service));
3134                 uses.add(d);
3135                 directives.add(d);
3136             }
3137             currentModule.uses = uses.toList();
3138             ListBuffer<ProvidesDirective> provides = new ListBuffer<>();
3139             for (InterimProvidesDirective interim : interimProvidesCopy) {
3140                 ListBuffer<ClassSymbol> impls = new ListBuffer<>();
3141                 for (Name impl : interim.impls) {
3142                     impls.append(syms.enterClass(currentModule, impl));
3143                 }
3144                 ProvidesDirective d = new ProvidesDirective(syms.enterClass(currentModule, interim.service),
3145                                                             impls.toList());
3146                 provides.add(d);
3147                 directives.add(d);
3148             }
3149             currentModule.provides = provides.toList();
3150             currentModule.directives = directives.toList();
3151         }
3152     }
3153 }