content: /*
   * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package openjdk.tools.javac.comp;
  
  import java.util.ArrayList;
  import java.util.HashSet;
  import java.util.Set;
  import java.util.function.BiConsumer;
  import java.util.stream.Collectors;
  
  import jdkx.tools.JavaFileObject;
  
  import openjdk.tools.javac.code.*;
  import openjdk.tools.javac.code.Lint.LintCategory;
  import openjdk.tools.javac.code.Scope.ImportFilter;
  import openjdk.tools.javac.code.Scope.NamedImportScope;
  import openjdk.tools.javac.code.Scope.StarImportScope;
  import openjdk.tools.javac.code.Scope.WriteableScope;
  import openjdk.tools.javac.code.Source.Feature;
  import openjdk.tools.javac.comp.Annotate.AnnotationTypeMetadata;
  import openjdk.tools.javac.tree.*;
  import openjdk.tools.javac.util.*;
  import openjdk.tools.javac.util.DefinedBy.Api;
  
  import openjdk.tools.javac.code.Symbol.*;
  import openjdk.tools.javac.code.Type.*;
  import openjdk.tools.javac.resources.CompilerProperties.Errors;
  import openjdk.tools.javac.tree.JCTree.*;
  
  import static openjdk.tools.javac.code.Flags.*;
  import static openjdk.tools.javac.code.Flags.ANNOTATION;
  import static openjdk.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
  import static openjdk.tools.javac.code.Kinds.Kind.*;
  import static openjdk.tools.javac.code.TypeTag.CLASS;
  import static openjdk.tools.javac.code.TypeTag.ERROR;
  import openjdk.tools.javac.resources.CompilerProperties.Fragments;
  
  import static openjdk.tools.javac.code.TypeTag.*;
  import static openjdk.tools.javac.tree.JCTree.Tag.*;
  
  import openjdk.tools.javac.util.Dependencies.CompletionCause;
  import openjdk.tools.javac.parser.Tokens.Comment;
  import openjdk.tools.javac.util.JCDiagnostic.DiagnosticFlag;
  import openjdk.tools.javac.util.JCDiagnostic.DiagnosticPosition;
  
  /** This is the second phase of Enter, in which classes are completed
   *  by resolving their headers and entering their members in the into
   *  the class scope. See Enter for an overall overview.
   *
   *  This class uses internal phases to process the classes. When a phase
   *  processes classes, the lower phases are not invoked until all classes
   *  pass through the current phase. Note that it is possible that upper phases
   *  are run due to recursive completion. The internal phases are:
   *  - ImportPhase: shallow pass through imports, adds information about imports
   *                 the NamedImportScope and StarImportScope, but avoids queries
   *                 about class hierarchy.
   *  - HierarchyPhase: resolves the supertypes of the given class. Does not handle
   *                    type parameters of the class or type argument of the supertypes.
   *  - HeaderPhase: finishes analysis of the header of the given class by resolving
   *                 type parameters, attributing supertypes including type arguments
   *                 and scheduling full annotation attribution. This phase also adds
   *                 a synthetic default constructor if needed and synthetic "this" field.
   *  - MembersPhase: resolves headers for fields, methods and constructors in the given class.
   *                  Also generates synthetic enum members.
   *
   *  <p><b>This is NOT part of any supported API.
   *  If you write code that depends on this, you do so at your own risk.
   *  This code and its internal interfaces are subject to change or
   *  deletion without notice.</b>
   */
  public class TypeEnter implements Completer {
      protected static final Context.Key<TypeEnter> typeEnterKey = new Context.Key<>();
  
      /** A switch to determine whether we check for package/class conflicts
       */
      static final boolean checkClash = true;
  
      private final Names names;
      private final Enter enter;
      private final MemberEnter memberEnter;
      private final Log log;
      private final Check chk;
      private final Attr attr;
      private final Symtab syms;
      private final TreeMaker make;
      private final Todo todo;
      private final Annotate annotate;
      private final TypeAnnotations typeAnnotations;
      private final Types types;
      private final JCDiagnostic.Factory diags;
      private final DeferredLintHandler deferredLintHandler;
      private final Lint lint;
      private final TypeEnvs typeEnvs;
      private final Dependencies dependencies;
  
      private final DeferredCompletionFailureHandler dcfh;
      private final JavacMessages messages;
      private final boolean ignoreNoLang;
  
      private final Preview preview;
  
  
      public static TypeEnter instance(Context context) {
          TypeEnter instance = context.get(typeEnterKey);
          if (instance == null)
              instance = new TypeEnter(context);
          return instance;
      }
  
      protected TypeEnter(Context context) {
          context.put(typeEnterKey, this);
          names = Names.instance(context);
          enter = Enter.instance(context);
          memberEnter = MemberEnter.instance(context);
          log = Log.instance(context);
          chk = Check.instance(context);
          attr = Attr.instance(context);
          syms = Symtab.instance(context);
          make = TreeMaker.instance(context);
          todo = Todo.instance(context);
          annotate = Annotate.instance(context);
          typeAnnotations = TypeAnnotations.instance(context);
          types = Types.instance(context);
          diags = JCDiagnostic.Factory.instance(context);
          deferredLintHandler = DeferredLintHandler.instance(context);
          lint = Lint.instance(context);
          typeEnvs = TypeEnvs.instance(context);
          dependencies = Dependencies.instance(context);
          preview = Preview.instance(context);
          Source source = Source.instance(context);
          allowTypeAnnos = Feature.TYPE_ANNOTATIONS.allowedInSource(source);
          allowDeprecationOnImport = Feature.DEPRECATION_ON_IMPORT.allowedInSource(source);
          Options options = Options.instance(context);
          boolean ideMode = options.get("ide") != null;
          boolean backgroundCompilation = options.get("backgroundCompilation") != null;
          ignoreNoLang = ideMode && !backgroundCompilation;
          dcfh = DeferredCompletionFailureHandler.instance(context);
          messages = JavacMessages.instance(context);
      }
  
      /** Switch: support type annotations.
       */
      boolean allowTypeAnnos;
  
      /**
       * Switch: should deprecation warnings be issued on import
       */
      boolean allowDeprecationOnImport;
  
      /** A flag to disable completion from time to time during member
       *  enter, as we only need to look up types.  This avoids
       *  unnecessarily deep recursion.
       */
      boolean completionEnabled = true;
  
      /* Verify Imports:
       */
      protected void ensureImportsChecked(List<JCCompilationUnit> trees) {
          // if there remain any unimported toplevels (these must have
          // no classes at all), process their import statements as well.
          for (JCCompilationUnit tree : trees) {
              if (!tree.starImportScope.isFilled()) {
                  Env<AttrContext> topEnv = enter.topLevelEnv(tree);
                  finishImports(tree, () -> {
                      try {
                          completeClass.resolveImports(tree, topEnv);
                      } catch (CompletionFailure ex) {
                          chk.completionError(tree.pos(), ex);
                      }
                  });
              }
          }
      }
  
  /* ********************************************************************
   * Source completer
   *********************************************************************/
  
      /** Complete entering a class.
       *  @param sym         The symbol of the class to be completed.
       */
      @Override
      public void complete(Symbol sym) throws CompletionFailure {
          // Suppress some (recursive) MemberEnter invocations
          if (!completionEnabled) {
              // Re-install same completer for next time around and return.
              Assert.check((sym.flags() & Flags.COMPOUND) == 0);
              sym.completer = this;
              return;
          }
  
          try {
              annotate.blockAnnotations();
              sym.flags_field |= UNATTRIBUTED;
  
              List<Env<AttrContext>> queue;
  
              dependencies.push((ClassSymbol) sym, CompletionCause.MEMBER_ENTER);
              try {
                  queue = completeClass.completeEnvs(List.of(typeEnvs.get((ClassSymbol) sym)));
              } finally {
                  dependencies.pop();
              }
  
              if (!queue.isEmpty()) {
                  Set<JCCompilationUnit> seen = new HashSet<>();
  
                  for (Env<AttrContext> env : queue) {
                      if (env.toplevel.defs.contains(env.enclClass) && seen.add(env.toplevel)) {
                          finishImports(env.toplevel, () -> {});
                      }
                  }
              }
          } finally {
              annotate.unblockAnnotations();
          }
      }
  
      void finishImports(JCCompilationUnit toplevel, Runnable resolve) {
          JavaFileObject prev = log.useSource(toplevel.sourcefile);
          try {
              resolve.run();
              chk.checkImportsUnique(toplevel);
              chk.checkImportsResolvable(toplevel);
              chk.checkImportedPackagesObservable(toplevel);
              toplevel.namedImportScope.finalizeScope();
              toplevel.starImportScope.finalizeScope();
          } catch (CompletionFailure cf) {
              chk.completionError(toplevel.pos(), cf);
          } finally {
              log.useSource(prev);
          }
      }
  
      abstract class Phase {
          private final ListBuffer<Env<AttrContext>> queue = new ListBuffer<>();
          private final Phase next;
          private final CompletionCause phaseName;
  
          Phase(CompletionCause phaseName, Phase next) {
              this.phaseName = phaseName;
              this.next = next;
          }
  
          public final List<Env<AttrContext>> completeEnvs(List<Env<AttrContext>> envs) {
              boolean firstToComplete = queue.isEmpty();
  
              Phase prevTopLevelPhase = topLevelPhase;
              boolean success = false;
  
              try {
                  topLevelPhase = this;
                  doCompleteEnvs(envs);
                  success = true;
              } finally {
                  topLevelPhase = prevTopLevelPhase;
                  if (!success && firstToComplete) {
                      //an exception was thrown, e.g. BreakAttr:
                      //the queue would become stale, clear it:
                      queue.clear();
                  }
              }
  
              if (firstToComplete) {
                  List<Env<AttrContext>> out = queue.toList();
  
                  queue.clear();
                  return next != null ? next.completeEnvs(out) : out;
              } else {
                  return List.nil();
              }
          }
  
          protected void doCompleteEnvs(List<Env<AttrContext>> envs) {
              for (Env<AttrContext> env : envs) {
                  JCClassDecl tree = (JCClassDecl)env.tree;
  
                  queue.add(env);
  
                  JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
                  DiagnosticPosition prevLintPos = deferredLintHandler.setPos(tree.pos());
                  try {
                      dependencies.push(env.enclClass.sym, phaseName);
                      runPhase(env);
                  } catch (CompletionFailure ex) {
                      if (ex.sym.kind != PCK || !names.java_lang.contentEquals(((PackageSymbol)ex.sym).fullname)) {
                          chk.completionError(tree.pos(), ex);
                      }
                  } catch (Attr.BreakAttr br) {
                      queue.clear();
                      throw br;
                  } finally {
                      dependencies.pop();
                      deferredLintHandler.setPos(prevLintPos);
                      log.useSource(prev);
                  }
              }
          }
  
          protected abstract void runPhase(Env<AttrContext> env);
      }
  
      private final ImportsPhase completeClass = new ImportsPhase();
      private Phase topLevelPhase;
  
      /**Analyze import clauses.
       */
      private final class ImportsPhase extends Phase {
  
          public ImportsPhase() {
              super(CompletionCause.IMPORTS_PHASE, new HierarchyPhase());
          }
  
          Env<AttrContext> env;
          ImportFilter staticImportFilter;
          ImportFilter typeImportFilter;
          BiConsumer<JCImport, CompletionFailure> cfHandler =
                  (imp, cf) -> chk.completionError(imp.pos(), cf);
  
          @Override
          protected void runPhase(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
  
              // If sym is a toplevel-class, make sure any import
              // clauses in its source file have been seen.
              if (sym.owner.kind == PCK) {
                  resolveImports(env.toplevel, env.enclosing(TOPLEVEL));
  //                if ((sym.flags_field & APT_CLEANED) != 0) {
  //                    todo.remove(sym);
  //                }
                  todo.append(env);
              }
  
              if (sym.owner.kind == TYP)
                  sym.owner.complete();
          }
  
          private void resolveImports(JCCompilationUnit tree, Env<AttrContext> env) {
              if (tree.starImportScope.isFilled()) {
                  // we must have already processed this toplevel
                  return;
              }
  
              ImportFilter prevStaticImportFilter = staticImportFilter;
              ImportFilter prevTypeImportFilter = typeImportFilter;
              DiagnosticPosition prevLintPos = deferredLintHandler.immediate();
              Lint prevLint = chk.setLint(lint);
              Env<AttrContext> prevEnv = this.env;
              try {
                  this.env = env;
                  final PackageSymbol packge = env.toplevel.packge;
                  this.staticImportFilter =
                          (origin, sym) -> sym.isStatic() &&
                                           chk.importAccessible(sym, packge) &&
                                           sym.isMemberOf((TypeSymbol) origin.owner, types);
                  this.typeImportFilter =
                          (origin, sym) -> sym.kind == TYP &&
                                           chk.importAccessible(sym, packge);
  
                  // Import-on-demand java.lang.
                  PackageSymbol javaLang = syms.enterPackage(syms.java_base, names.java_lang);
                  if (javaLang.members().isEmpty() && !javaLang.exists() || syms.java_base.kind == ERR) {
                      JCDiagnostic msg = diags.fragment(Fragments.FatalErrNoJavaLang);
                      if (ignoreNoLang) {
                          throw new CompletionFailure(javaLang, () -> {
                              return msg;
                          }, dcfh);
                      }
                      else {
                          throw new MissingPlatformError (msg);
                      }
                  }
                  importAll(make.at(tree.pos()).Import(make.QualIdent(javaLang), false), javaLang, env);
  
                  JCModuleDecl decl = tree.getModuleDecl();
  
                  // Process the package def and all import clauses.
                  if (tree.getPackage() != null && decl == null)
                      checkClassPackageClash(tree.getPackage());
  
                  for (JCImport imp : tree.getImports()) {
                      doImport(imp);
                  }
  
                  if (decl != null) {
                      //check @Deprecated:
                      markDeprecated(decl.sym, decl.mods.annotations, env);
                      // process module annotations
                      annotate.annotateLater(decl.mods.annotations, env, env.toplevel.modle, null);
                  }
              } finally {
                  this.env = prevEnv;
                  chk.setLint(prevLint);
                  deferredLintHandler.setPos(prevLintPos);
                  this.staticImportFilter = prevStaticImportFilter;
                  this.typeImportFilter = prevTypeImportFilter;
              }
          }
  
          private void checkClassPackageClash(JCPackageDecl tree) {
              // check that no class exists with same fully qualified name as
              // toplevel package
              if (checkClash && tree.pid != null) {
                  Symbol p = env.toplevel.packge;
                  while (p.owner != syms.rootPackage) {
                      p.owner.complete(); // enter all class members of p
                      //need to lookup the owning module/package:
                      PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, p.owner.getQualifiedName());
                      if (syms.getClass(pack.modle, p.getQualifiedName()) != null) {
                          log.error(tree.pos,
                                    Errors.PkgClashesWithClassOfSameName(p));
                      }
                      p = p.owner;
                  }
              }
              // process package annotations
              annotate.annotateLater(tree.annotations, env, env.toplevel.packge, null);
          }
  
          private void doImport(JCImport tree) {
              JCFieldAccess imp = (JCFieldAccess)tree.qualid;
              Name name = TreeInfo.name(imp);
  
              // Create a local environment pointing to this tree to disable
              // effects of other imports in Resolve.findGlobalType
              Env<AttrContext> localEnv = env.dup(tree);
  
              TypeSymbol p = attr.attribImportQualifier(tree, localEnv).tsym;
              if (name == names.asterisk) {
                  // Import on demand.
                  chk.checkCanonical(imp.selected);
                  if (tree.staticImport)
                      importStaticAll(tree, p, env);
                  else
                      importAll(tree, p, env);
              } else {
                  // Named type import.
                  if (tree.staticImport) {
                      importNamedStatic(tree, p, name, localEnv);
                      chk.checkCanonical(imp.selected);
                  } else {
                      Type importedType = attribImportType(imp, localEnv);
                      Type originalType = importedType.getOriginalType();
                      TypeSymbol c = originalType.hasTag(CLASS) ? originalType.tsym : importedType.tsym;
                      chk.checkCanonical(imp);
                      importNamed(tree.pos(), c, env, tree);
                  }
              }
          }
  
          Type attribImportType(JCTree tree, Env<AttrContext> env) {
              Assert.check(completionEnabled);
              Lint prevLint = chk.setLint(allowDeprecationOnImport ?
                      lint : lint.suppress(LintCategory.DEPRECATION, LintCategory.REMOVAL, LintCategory.PREVIEW));
              try {
                  // To prevent deep recursion, suppress completion of some
                  // types.
                  completionEnabled = false;
                  return attr.attribType(tree, env);
              } finally {
                  completionEnabled = true;
                  chk.setLint(prevLint);
              }
          }
  
          /** Import all classes of a class or package on demand.
           *  @param imp           The import that is being handled.
           *  @param tsym          The class or package the members of which are imported.
           *  @param env           The env in which the imported classes will be entered.
           */
          private void importAll(JCImport imp,
                                 final TypeSymbol tsym,
                                 Env<AttrContext> env) {
              env.toplevel.starImportScope.importAll(types, tsym.members(), typeImportFilter, imp, cfHandler);
          }
  
          /** Import all static members of a class or package on demand.
           *  @param imp           The import that is being handled.
           *  @param tsym          The class or package the members of which are imported.
           *  @param env           The env in which the imported classes will be entered.
           */
          private void importStaticAll(JCImport imp,
                                       final TypeSymbol tsym,
                                       Env<AttrContext> env) {
              final StarImportScope toScope = env.toplevel.starImportScope;
              final TypeSymbol origin = tsym;
  
              toScope.importAll(types, origin.members(), staticImportFilter, imp, cfHandler);
          }
  
          /** Import statics types of a given name.  Non-types are handled in Attr.
           *  @param imp           The import that is being handled.
           *  @param tsym          The class from which the name is imported.
           *  @param name          The (simple) name being imported.
           *  @param env           The environment containing the named import
           *                  scope to add to.
           */
          private void importNamedStatic(final JCImport imp,
                                         final TypeSymbol tsym,
                                         final Name name,
                                         final Env<AttrContext> env) {
              if (tsym.kind != TYP) {
                  log.error(DiagnosticFlag.RECOVERABLE, imp.pos(), Errors.StaticImpOnlyClassesAndInterfaces);
                  return;
              }
  
              final NamedImportScope toScope = env.toplevel.namedImportScope;
              final Scope originMembers = tsym.members();
  
              imp.importScope = toScope.importByName(types, originMembers, name, staticImportFilter, imp, cfHandler);
          }
  
          /** Import given class.
           *  @param pos           Position to be used for error reporting.
           *  @param tsym          The class to be imported.
           *  @param env           The environment containing the named import
           *                  scope to add to.
           */
          private void importNamed(DiagnosticPosition pos, final Symbol tsym, Env<AttrContext> env, JCImport imp) {
              if (tsym.kind == TYP || tsym.kind == ERR)
                  imp.importScope = env.toplevel.namedImportScope.importType(tsym.owner.members(), tsym.owner.members(), tsym);
          }
  
      }
  
      /**Defines common utility methods used by the HierarchyPhase and HeaderPhase.
       */
      private abstract class AbstractHeaderPhase extends Phase {
  
          public AbstractHeaderPhase(CompletionCause phaseName, Phase next) {
              super(phaseName, next);
          }
  
  
          protected Env<AttrContext> baseEnv(JCClassDecl tree, Env<AttrContext> env) {
              WriteableScope baseScope = WriteableScope.create(tree.sym);
              //import already entered local classes into base scope
              for (Symbol sym : env.outer.info.scope.getSymbols(NON_RECURSIVE)) {
                  if (sym.isDirectlyOrIndirectlyLocal()) {
                      baseScope.enter(sym);
                  }
              }
              //import current type-parameters into base scope
              if (tree.typarams != null)
                  for (List<JCTypeParameter> typarams = tree.typarams;
                       typarams.nonEmpty();
                       typarams = typarams.tail)
                      baseScope.enter(typarams.head.type.tsym);
              Env<AttrContext> outer = env.outer; // the base clause can't see members of this class
              Env<AttrContext> localEnv = outer.dup(tree, outer.info.dup(baseScope));
              localEnv.baseClause = true;
              localEnv.outer = outer;
              localEnv.info.isSelfCall = false;
              return localEnv;
          }
  
  
          /** Generate a base clause for an enum type.
           *  @param pos              The position for trees and diagnostics, if any
           *  @param c                The class symbol of the enum
           */
          protected  JCExpression enumBase(int pos, ClassSymbol c) {
              JCExpression result = make.at(pos).
                  TypeApply(make.QualIdent(syms.enumSym),
                            List.of(make.Type(c.type)));
              return result;
          }
  
          protected Type modelMissingTypes(Env<AttrContext> env, Type t, final JCExpression tree, final boolean interfaceExpected) {
              if (!t.hasTag(ERROR) || tree == null)
                  return t;
  
              return new ErrorType(t.getOriginalType(), t.tsym) {
                  private Type modelType;
  
                  @Override
                  public Type getModelType() {
                      if (modelType == null)
                          modelType = new Synthesizer(env.toplevel.modle, getOriginalType(), interfaceExpected).visit(tree);
                      return modelType;
                  }
              };
          }
              // where:
              private class Synthesizer extends JCTree.Visitor {
                  ModuleSymbol msym;
                  Type originalType;
                  boolean interfaceExpected;
                  List<ClassSymbol> synthesizedSymbols = List.nil();
                  Type result;
  
                  Synthesizer(ModuleSymbol msym, Type originalType, boolean interfaceExpected) {
                      this.msym = msym;
                      this.originalType = originalType;
                      this.interfaceExpected = interfaceExpected;
                  }
  
                  Type visit(JCTree tree) {
                      tree.accept(this);
                      return result;
                  }
  
                  List<Type> visit(List<? extends JCTree> trees) {
                      ListBuffer<Type> lb = new ListBuffer<>();
                      for (JCTree t: trees)
                          lb.append(visit(t));
                      return lb.toList();
                  }
  
                  @Override
                  public void visitTree(JCTree tree) {
                      result = syms.errType;
                  }
  
                  @Override
                  public void visitIdent(JCIdent tree) {
                      if (tree.type != null && !tree.type.hasTag(ERROR)) {
                          result = tree.type;
                      } else {
                          result = synthesizeClass(tree.name, msym.unnamedPackage).type;
                      }
                  }
  
                  @Override
                  public void visitSelect(JCFieldAccess tree) {
                      if (!tree.type.hasTag(ERROR)) {
                          result = tree.type;
                      } else {
                          Type selectedType;
                          boolean prev = interfaceExpected;
                          try {
                              interfaceExpected = false;
                              selectedType = visit(tree.selected);
                          } finally {
                              interfaceExpected = prev;
                          }
                          ClassSymbol c = synthesizeClass(tree.name, selectedType.tsym);
                          result = c.type;
                      }
                  }
  
                  @Override
                  public void visitTypeApply(JCTypeApply tree) {
                      if (!tree.type.hasTag(ERROR)) {
                          result = tree.type;
                      } else {
                          ClassType clazzType = (ClassType) visit(tree.clazz);
                          if (synthesizedSymbols.contains(clazzType.tsym))
                              synthesizeTyparams((ClassSymbol) clazzType.tsym, tree.arguments.size());
                          final List<Type> actuals = visit(tree.arguments);
                          result = new ErrorType(tree.type, clazzType.tsym) {
                              @Override @DefinedBy(Api.LANGUAGE_MODEL)
                              public List<Type> getTypeArguments() {
                                  return actuals;
                              }
                          };
                      }
                  }
  
                  ClassSymbol synthesizeClass(Name name, Symbol owner) {
                      int flags = interfaceExpected ? INTERFACE : 0;
                      ClassSymbol c = new ClassSymbol(flags, name, owner);
                      c.members_field = new Scope.ErrorScope(c);
                      c.type = new ErrorType(originalType, c) {
                          @Override @DefinedBy(Api.LANGUAGE_MODEL)
                          public List<Type> getTypeArguments() {
                              return typarams_field;
                          }
                      };
                      synthesizedSymbols = synthesizedSymbols.prepend(c);
                      return c;
                  }
  
                  void synthesizeTyparams(ClassSymbol sym, int n) {
                      ClassType ct = (ClassType) sym.type;
                      Assert.check(ct.typarams_field.isEmpty());
                      if (n == 1) {
                          TypeVar v = new TypeVar(names.fromString("T"), sym, syms.botType);
                          ct.typarams_field = ct.typarams_field.prepend(v);
                      } else {
                          for (int i = n; i > 0; i--) {
                              TypeVar v = new TypeVar(names.fromString("T" + i), sym,
                                                      syms.botType);
                              ct.typarams_field = ct.typarams_field.prepend(v);
                          }
                      }
                  }
              }
  
          protected void attribSuperTypes(Env<AttrContext> env, Env<AttrContext> baseEnv) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
              ClassType ct = (ClassType)sym.type;
              // Determine supertype.
              Type supertype;
              JCExpression extending;
  
              if (tree.extending != null) {
                  extending = clearTypeParams(tree.extending);
                  supertype = attr.attribBase(extending, baseEnv, true, false, true);
                  if (supertype == syms.recordType) {
                      log.error(tree, Errors.InvalidSupertypeRecord(supertype.tsym));
                  }
              } else {
                  extending = null;
                  supertype = ((tree.mods.flags & Flags.ENUM) != 0)
                  ? attr.attribBase(enumBase(tree.pos, sym), baseEnv,
                                    true, false, false)
                  : (sym.fullname == names.java_lang_Object)
                  ? Type.noType
                  : sym.isRecord() ? syms.recordType : syms.objectType;
              }
              ct.supertype_field = modelMissingTypes(baseEnv, supertype, extending, false);
  
              // Determine interfaces.
              ListBuffer<Type> interfaces = new ListBuffer<>();
              ListBuffer<Type> all_interfaces = null; // lazy init
              List<JCExpression> interfaceTrees = tree.implementing;
              for (JCExpression iface : interfaceTrees) {
                  iface = clearTypeParams(iface);
                  Type it = attr.attribBase(iface, baseEnv, false, true, true);
                  if (it.hasTag(CLASS)) {
                      interfaces.append(it);
                      if (all_interfaces != null) all_interfaces.append(it);
                  } else {
                      if (all_interfaces == null)
                          all_interfaces = new ListBuffer<Type>().appendList(interfaces);
                      all_interfaces.append(modelMissingTypes(baseEnv, it, iface, true));
                  }
              }
  
              // Determine permits.
              ListBuffer<Symbol> permittedSubtypeSymbols = new ListBuffer<>();
              List<JCExpression> permittedTrees = tree.permitting;
              for (JCExpression permitted : permittedTrees) {
                  Type pt = attr.attribBase(permitted, baseEnv, false, false, false);
                  permittedSubtypeSymbols.append(pt.tsym);
              }
  
              if ((sym.flags_field & ANNOTATION) != 0) {
                  ct.interfaces_field = List.of(syms.annotationType);
                  ct.all_interfaces_field = ct.interfaces_field;
              }  else {
                  ct.interfaces_field = interfaces.toList();
                  ct.all_interfaces_field = (all_interfaces == null)
                          ? ct.interfaces_field : all_interfaces.toList();
              }
  
              /* it could be that there are already some symbols in the permitted list, for the case
               * where there are subtypes in the same compilation unit but the permits list is empty
               * so don't overwrite the permitted list if it is not empty
               */
              if (!permittedSubtypeSymbols.isEmpty()) {
                  sym.permitted = permittedSubtypeSymbols.toList();
              }
              sym.isPermittedExplicit = !permittedSubtypeSymbols.isEmpty();
          }
              //where:
              protected JCExpression clearTypeParams(JCExpression superType) {
                  return superType;
              }
      }
  
      private final class HierarchyPhase extends AbstractHeaderPhase implements Completer {
  
          public HierarchyPhase() {
              super(CompletionCause.HIERARCHY_PHASE, new PermitsPhase());
          }
  
          @Override
          protected void doCompleteEnvs(List<Env<AttrContext>> envs) {
              //The ClassSymbols in the envs list may not be in the dependency order.
              //To get proper results, for every class or interface C, the supertypes of
              //C must be processed by the HierarchyPhase phase before C.
              //To achieve that, the HierarchyPhase is registered as the Completer for
              //all the classes first, and then all the classes are completed.
              for (Env<AttrContext> env : envs) {
                  env.enclClass.sym.completer = this;
              }
              for (Env<AttrContext> env : envs) {
                  env.enclClass.sym.complete();
              }
          }
  
          @Override
          protected void runPhase(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
              ClassType ct = (ClassType)sym.type;
  
              Env<AttrContext> baseEnv = baseEnv(tree, env);
  
              attribSuperTypes(env, baseEnv);
  
              if (sym.fullname == names.java_lang_Object) {
                  if (tree.extending != null) {
                      chk.checkNonCyclic(tree.extending.pos(),
                                         ct.supertype_field);
                      ct.supertype_field = Type.noType;
                  }
                  else if (tree.implementing.nonEmpty()) {
                      chk.checkNonCyclic(tree.implementing.head.pos(),
                                         ct.interfaces_field.head);
                      ct.interfaces_field = List.nil();
                  }
              }
  
              markDeprecated(sym, tree.mods.annotations, baseEnv);
  
              chk.checkNonCyclicDecl(tree);
          }
              //where:
              @Override
              protected JCExpression clearTypeParams(JCExpression superType) {
                  switch (superType.getTag()) {
                      case TYPEAPPLY:
                          return ((JCTypeApply) superType).clazz;
                  }
  
                  return superType;
              }
  
          @Override
          public void complete(Symbol sym) throws CompletionFailure {
              Assert.check((topLevelPhase instanceof ImportsPhase) ||
                           (topLevelPhase == this));
  
              if (topLevelPhase != this) {
                  //only do the processing based on dependencies in the HierarchyPhase:
                  sym.completer = this;
                  return ;
              }
  
              Env<AttrContext> env = typeEnvs.get((ClassSymbol) sym);
  
              super.doCompleteEnvs(List.of(env));
          }
  
      }
  
      private final class PermitsPhase extends AbstractHeaderPhase {
  
          public PermitsPhase() {
              super(CompletionCause.HIERARCHY_PHASE, new HeaderPhase());
          }
  
          @Override
          protected void runPhase(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              if (!tree.sym.isAnonymous() || tree.sym.isEnum()) {
                  for (Type supertype : types.directSupertypes(tree.sym.type)) {
                      if (supertype.tsym.kind == TYP) {
                          ClassSymbol supClass = (ClassSymbol) supertype.tsym;
                          Env<AttrContext> supClassEnv = enter.getEnv(supClass);
                          if (supClass.isSealed() &&
                              !supClass.isPermittedExplicit &&
                              supClassEnv != null &&
                              supClassEnv.toplevel == env.toplevel) {
                              supClass.permitted = supClass.permitted.append(tree.sym);
                          }
                      }
                  }
              }
          }
  
      }
  
      private final class HeaderPhase extends AbstractHeaderPhase {
  
          public HeaderPhase() {
              super(CompletionCause.HEADER_PHASE, new RecordPhase());
          }
  
          @Override
          protected void runPhase(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
              ClassType ct = (ClassType)sym.type;
  
              // create an environment for evaluating the base clauses
              Env<AttrContext> baseEnv = baseEnv(tree, env);
  
              if (tree.extending != null)
                  annotate.queueScanTreeAndTypeAnnotate(tree.extending, baseEnv, sym, tree.pos());
              for (JCExpression impl : tree.implementing)
                  annotate.queueScanTreeAndTypeAnnotate(impl, baseEnv, sym, tree.pos());
              annotate.flush();
  
              attribSuperTypes(env, baseEnv);
  
              Set<Type> interfaceSet = new HashSet<>();
  
              for (JCExpression iface : tree.implementing) {
                  Type it = iface.type;
                  if (it.hasTag(CLASS))
                      chk.checkNotRepeated(iface.pos(), types.erasure(it), interfaceSet);
              }
  
              annotate.annotateLater(tree.mods.annotations, baseEnv,
                          sym, tree.pos());
              attr.attribTypeVariables(tree.typarams, baseEnv, false);
  
              for (JCTypeParameter tp : tree.typarams)
                  annotate.queueScanTreeAndTypeAnnotate(tp, baseEnv, sym, tree.pos());
  
              // check that no package exists with same fully qualified name,
              // but admit classes in the unnamed package which have the same
              // name as a top-level package.
              if (checkClash &&
                  sym.owner.kind == PCK && sym.owner != env.toplevel.modle.unnamedPackage &&
                  syms.packageExists(env.toplevel.modle, sym.fullname)) {
                  log.error(tree.pos, Errors.ClashWithPkgOfSameName(Kinds.kindName(sym),sym));
              }
              if (sym.owner.kind == PCK && (sym.flags_field & PUBLIC) == 0 &&
                  !env.toplevel.sourcefile.isNameCompatible(sym.name.toString(),JavaFileObject.Kind.SOURCE)) {
                  sym.flags_field |= AUXILIARY;
              }
          }
      }
  
      private abstract class AbstractMembersPhase extends Phase {
  
          public AbstractMembersPhase(CompletionCause completionCause, Phase next) {
              super(completionCause, next);
          }
  
          private boolean completing;
          private List<Env<AttrContext>> todo = List.nil();
  
          @Override
          protected void doCompleteEnvs(List<Env<AttrContext>> envs) {
              todo = todo.prependList(envs);
              if (completing) {
                  return ; //the top-level invocation will handle all envs
              }
              boolean prevCompleting = completing;
              completing = true;
              try {
                  while (todo.nonEmpty()) {
                      Env<AttrContext> head = todo.head;
                      todo = todo.tail;
                      super.doCompleteEnvs(List.of(head));
                  }
              } finally {
                  completing = prevCompleting;
              }
          }
  
          void enterThisAndSuper(ClassSymbol sym, Env<AttrContext> env) {
              ClassType ct = (ClassType)sym.type;
  
  
  
              // enter symbols for 'this' into current scope.
              VarSymbol thisSym =
                      new VarSymbol(FINAL | HASINIT, names._this, sym.type, sym);
              thisSym.pos = Position.FIRSTPOS;
              env.info.scope.enter(thisSym);
              // if this is a class, enter symbol for 'super' into current scope.
              if ((sym.flags_field & INTERFACE) == 0 &&
                      ct.supertype_field.hasTag(CLASS)) {
                  VarSymbol superSym =
                          new VarSymbol(FINAL | HASINIT, names._super,
                                  ct.supertype_field, sym);
                  superSym.pos = Position.FIRSTPOS;
                  env.info.scope.enter(superSym);
              }
          }
      }
  
      private final class RecordPhase extends AbstractMembersPhase {
  
          public RecordPhase() {
              super(CompletionCause.RECORD_PHASE, new MembersPhase());
          }
  
          @Override
          protected void runPhase(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
              if ((sym.flags_field & RECORD) != 0) {
                  List<JCVariableDecl> fields = TreeInfo.recordFields(tree);
                  memberEnter.memberEnter(fields, env);
                  for (JCVariableDecl field : fields) {
                      sym.getRecordComponent(field, true,
                              field.mods.annotations.isEmpty() ?
                                      List.nil() :
                                      new TreeCopier<JCTree>(make.at(field.pos)).copy(field.mods.annotations));
                  }
  
                  enterThisAndSuper(sym, env);
  
                  // lets enter all constructors
                  for (JCTree def : tree.defs) {
                      if (TreeInfo.isConstructor(def)) {
                          memberEnter.memberEnter(def, env);
                      }
                  }
              }
          }
      }
  
      /** Enter member fields and methods of a class
       */
      private final class MembersPhase extends AbstractMembersPhase {
  
          public MembersPhase() {
              super(CompletionCause.MEMBERS_PHASE, null);
          }
  
          @Override
          protected void runPhase(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
              ClassType ct = (ClassType)sym.type;
  
              JCTree defaultConstructor = null;
  
              // Add default constructor if needed.
              DefaultConstructorHelper helper = getDefaultConstructorHelper(env);
              if (helper != null) {
                  chk.checkDefaultConstructor(sym, tree.pos());
                  defaultConstructor = defaultConstructor(make.at(tree.pos), helper);
                  tree.defs = tree.defs.prepend(defaultConstructor);
              }
              if (!sym.isRecord()) {
                  enterThisAndSuper(sym, env);
              }
  
              if (!tree.typarams.isEmpty()) {
                  for (JCTypeParameter tvar : tree.typarams) {
                      chk.checkNonCyclic(tvar, (TypeVar)tvar.type);
                  }
              }
  
              finishClass(tree, defaultConstructor, env);
  
              if (allowTypeAnnos) {
                  typeAnnotations.organizeTypeAnnotationsSignatures(env, (JCClassDecl)env.tree);
                  typeAnnotations.validateTypeAnnotationsSignatures(env, (JCClassDecl)env.tree);
              }
          }
  
          DefaultConstructorHelper getDefaultConstructorHelper(Env<AttrContext> env) {
              JCClassDecl tree = env.enclClass;
              ClassSymbol sym = tree.sym;
              DefaultConstructorHelper helper = null;
              boolean isClassWithoutInit = (sym.flags() & INTERFACE) == 0 && !TreeInfo.hasConstructors(tree.defs);
              boolean isRecord = sym.isRecord();
              if (isClassWithoutInit && !isRecord) {
                  helper = new BasicConstructorHelper(sym);
                  if (sym.name.isEmpty()) {
                      JCNewClass nc = (JCNewClass)env.next.tree;
                      if (nc.constructor != null) {
                          if (nc.constructor.kind != ERR) {
                              helper = new AnonClassConstructorHelper(sym, (MethodSymbol)nc.constructor, nc.encl);
                          } else {
                              helper = null;
                          }
                      }
                  }
              }
              if (isRecord) {
                  JCMethodDecl canonicalInit = null;
                  if (isClassWithoutInit || (canonicalInit = getCanonicalConstructorDecl(env.enclClass)) == null) {
                      helper = new RecordConstructorHelper(sym, TreeInfo.recordFields(tree));
                  }
                  if (canonicalInit != null) {
                      canonicalInit.sym.flags_field |= Flags.RECORD;
                  }
              }
              return helper;
          }
  
          /** Enter members for a class.
           */
          void finishClass(JCClassDecl tree, JCTree defaultConstructor, Env<AttrContext> env) {
              if ((tree.mods.flags & Flags.ENUM) != 0 &&
                  !tree.sym.type.hasTag(ERROR)) {
                  Type supertype = types.supertype(tree.sym.type);
                  if (supertype != null && !supertype.hasTag(TypeTag.NONE)
                          && (supertype.tsym.flags() & Flags.ENUM) == 0
                          && (tree.sym.flags_field & Flags.FROMCLASS) == 0) {
                          addEnumMembers(tree, env);
                  }
              }
              boolean isRecord = (tree.sym.flags_field & RECORD) != 0;
              List<JCTree> alreadyEntered = null;
              if (isRecord) {
                  alreadyEntered = List.convert(JCTree.class, TreeInfo.recordFields(tree));
                  alreadyEntered = alreadyEntered.prependList(tree.defs.stream()
                          .filter(t -> TreeInfo.isConstructor(t) && t != defaultConstructor).collect(List.collector()));
              }
              List<JCTree> defsToEnter = isRecord ?
                      tree.defs.diff(alreadyEntered) : tree.defs;
              memberEnter.memberEnter(defsToEnter, env);
              if (isRecord) {
                  addRecordMembersIfNeeded(tree, env);
              }
              if (tree.sym.isAnnotationType()) {
                  Assert.check(tree.sym.isCompleted());
                  if ((tree.sym.flags_field & FROMCLASS) != 0) {
                      tree.sym.clearAnnotationTypeMetadata();
                  }
                  tree.sym.setAnnotationTypeMetadata(new AnnotationTypeMetadata(tree.sym, annotate.annotationTypeSourceCompleter()));
              }
          }
  
          private void addAccessor(JCVariableDecl tree, Env<AttrContext> env) {
              MethodSymbol implSym = lookupMethod(env.enclClass.sym, tree.sym.name, List.nil());
              RecordComponent rec = ((ClassSymbol) tree.sym.owner).getRecordComponent(tree.sym);
              if (implSym == null || (implSym.flags_field & GENERATED_MEMBER) != 0) {
                  /* here we are pushing the annotations present in the corresponding field down to the accessor
                   * it could be that some of those annotations are not applicable to the accessor, they will be striped
                   * away later at Check::validateAnnotation
                   */
                  TreeCopier<JCTree> tc = new TreeCopier<JCTree>(make.at(tree.pos));
                  List<JCAnnotation> originalAnnos = rec.getOriginalAnnos().isEmpty() ?
                          rec.getOriginalAnnos() :
                          tc.copy(rec.getOriginalAnnos());
                  JCVariableDecl recordField = TreeInfo.recordFields((JCClassDecl) env.tree).stream().filter(rf -> rf.name == tree.name).findAny().get();
                  JCMethodDecl getter = make.at(tree.pos).
                          MethodDef(
                                  make.Modifiers(PUBLIC | Flags.GENERATED_MEMBER, originalAnnos),
                            tree.sym.name,
                            /* we need to special case for the case when the user declared the type as an ident
                             * if we don't do that then we can have issues if type annotations are applied to the
                             * return type: javac issues an error if a type annotation is applied to java.lang.String
                             * but applying a type annotation to String is kosher
                             */
                            tc.copy(recordField.vartype),
                            List.nil(),
                            List.nil(),
                            List.nil(), // thrown
                            null,
                            null);
                  memberEnter.memberEnter(getter, env);
                  rec.accessor = getter.sym;
                  rec.accessorMeth = getter;
              } else if (implSym != null) {
                  rec.accessor = implSym;
              }
          }
  
          /** Add the implicit members for an enum type
           *  to the symbol table.
           */
          private void addEnumMembers(JCClassDecl tree, Env<AttrContext> env) {
              JCExpression valuesType = make.Type(new ArrayType(tree.sym.type, syms.arrayClass));
  
              // public static T[] values() { return ???; }
              JCMethodDecl values = make.at(Position.NOPOS).
                  MethodDef(make.Modifiers(Flags.PUBLIC|Flags.STATIC),
                            names.values,
                            valuesType,
                            List.nil(),
                            List.nil(),
                            List.nil(),
                            null,
                            null);
              class HardcodedComment implements Comment {
                  private final String key;
                  public HardcodedComment(String key) {
                      this.key = key;
                  }
                  public String getText() {
                      return messages.getLocalizedString(key); //NOI18N
                  }
                  public int getSourcePos(int index) {
                      return -1;
                  }
                  public CommentStyle getStyle() {
                      return CommentStyle.JAVADOC;
                  }
                  public boolean isDeprecated() {
                      return false;
                  }
              }
              DocCommentTable docComments = env.toplevel.docComments;
              if (docComments != null)
                  docComments.putComment(values, new HardcodedComment("compiler.javadoc.enum.values")); //NOI18N
              memberEnter.memberEnter(values, env);
  
              JCMethodDecl valueOf = make.
                  MethodDef(make.Modifiers(Flags.PUBLIC|Flags.STATIC),
                            names.valueOf,
                            make.Type(tree.sym.type),
                            List.nil(),
                            List.of(make.VarDef(make.Modifiers(Flags.PARAMETER |
                                                               Flags.MANDATED),
                                                  names.fromString("name"),
                                                  make.Type(syms.stringType), null)),
                            List.nil(),
                            null,
                            null);
              if (docComments != null)
                  docComments.putComment(valueOf, new HardcodedComment("compiler.javadoc.enum.valueOf")); //NOI18N
              memberEnter.memberEnter(valueOf, env);
          }
  
          JCMethodDecl getCanonicalConstructorDecl(JCClassDecl tree) {
              // let's check if there is a constructor with exactly the same arguments as the record components
              List<Type> recordComponentErasedTypes = types.erasure(TreeInfo.recordFields(tree).map(vd -> vd.sym.type));
              JCMethodDecl canonicalDecl = null;
              for (JCTree def : tree.defs) {
                  if (TreeInfo.isConstructor(def)) {
                      JCMethodDecl mdecl = (JCMethodDecl)def;
                      if (types.isSameTypes(types.erasure(mdecl.params.stream().map(v -> v.sym.type).collect(List.collector())), recordComponentErasedTypes)) {
                          canonicalDecl = mdecl;
                          break;
                      }
                  }
              }
              return canonicalDecl;
          }
  
          /** Add the implicit members for a record
           *  to the symbol table.
           */
          private void addRecordMembersIfNeeded(JCClassDecl tree, Env<AttrContext> env) {
              if (lookupMethod(tree.sym, names.toString, List.nil()) == null) {
                  JCMethodDecl toString = make.
                      MethodDef(make.Modifiers(Flags.PUBLIC | Flags.RECORD | Flags.FINAL | Flags.GENERATED_MEMBER),
                                names.toString,
                                make.Type(syms.stringType),
                                List.nil(),
                                List.nil(),
                                List.nil(),
                                null,
                                null);
                  memberEnter.memberEnter(toString, env);
              }
  
              if (lookupMethod(tree.sym, names.hashCode, List.nil()) == null) {
                  JCMethodDecl hashCode = make.
                      MethodDef(make.Modifiers(Flags.PUBLIC | Flags.RECORD | Flags.FINAL | Flags.GENERATED_MEMBER),
                                names.hashCode,
                                make.Type(syms.intType),
                                List.nil(),
                                List.nil(),
                                List.nil(),
                                null,
                                null);
                  memberEnter.memberEnter(hashCode, env);
              }
  
              if (lookupMethod(tree.sym, names.equals, List.of(syms.objectType)) == null) {
                  JCMethodDecl equals = make.
                      MethodDef(make.Modifiers(Flags.PUBLIC | Flags.RECORD | Flags.FINAL | Flags.GENERATED_MEMBER),
                                names.equals,
                                make.Type(syms.booleanType),
                                List.nil(),
                                List.of(make.VarDef(make.Modifiers(Flags.PARAMETER),
                                                  names.fromString("o"),
                                                  make.Type(syms.objectType), null)),
                                List.nil(),
                                null,
                                null);
                  memberEnter.memberEnter(equals, env);
              }
  
              // fields can't be varargs, lets remove the flag
              List<JCVariableDecl> recordFields = TreeInfo.recordFields(tree);
              for (JCVariableDecl field: recordFields) {
                  field.mods.flags &= ~Flags.VARARGS;
                  field.sym.flags_field &= ~Flags.VARARGS;
              }
              // now lets add the accessors
              recordFields.stream()
                      .filter(vd -> (lookupMethod(syms.objectType.tsym, vd.name, List.nil()) == null))
                      .forEach(vd -> addAccessor(vd, env));
          }
      }
  
      Env<AttrContext> baseEnv(JCClassDecl tree, Env<AttrContext> env) {
          WriteableScope baseScope = WriteableScope.create(tree.sym);
          //import already entered local classes into base scope
          for (Symbol sym : env.outer.info.scope.getSymbols(NON_RECURSIVE)) {
              if (sym.isDirectlyOrIndirectlyLocal()) {
                  baseScope.enter(sym);
              }
          }
          //import current type-parameters into base scope
          if (tree.typarams != null)
              for (List<JCTypeParameter> typarams = tree.typarams;
                   typarams.nonEmpty();
                   typarams = typarams.tail)
                  baseScope.enter(typarams.head.type.tsym);
          Env<AttrContext> outer = env.outer; // the base clause can't see members of this class
          Env<AttrContext> localEnv = outer.dup(tree, outer.info.dup(baseScope));
          localEnv.baseClause = true;
          localEnv.outer = outer;
          localEnv.info.isSelfCall = false;
          return localEnv;
      }
  
      public Env<AttrContext> getBaseEnv(JCClassDecl tree, Env<AttrContext> env) {
          if (tree.sym == null)
              return null;
          Env<AttrContext> bEnv = baseEnv(tree, env);
          return bEnv;
      }
  
      private MethodSymbol lookupMethod(TypeSymbol tsym, Name name, List<Type> argtypes) {
          for (Symbol s : tsym.members().getSymbolsByName(name, s -> s.kind == MTH)) {
              if (types.isSameTypes(s.type.getParameterTypes(), argtypes)) {
                  return (MethodSymbol) s;
              }
          }
          return null;
      }
  
  /* ***************************************************************************
   * tree building
   ****************************************************************************/
  
      interface DefaultConstructorHelper {
         Type constructorType();
         MethodSymbol constructorSymbol();
         Type enclosingType();
         TypeSymbol owner();
         List<Name> superArgs();
         default JCMethodDecl finalAdjustment(JCMethodDecl md) { return md; }
      }
  
      class BasicConstructorHelper implements DefaultConstructorHelper {
  
          TypeSymbol owner;
          Type constructorType;
          MethodSymbol constructorSymbol;
  
          BasicConstructorHelper(TypeSymbol owner) {
              this.owner = owner;
          }
  
          @Override
          public Type constructorType() {
              if (constructorType == null) {
                  constructorType = new MethodType(List.nil(), null, List.nil(), syms.methodClass);
              }
              return constructorType;
          }
  
          @Override
          public MethodSymbol constructorSymbol() {
              if (constructorSymbol == null) {
                  long flags;
                  if ((owner().flags() & ENUM) != 0 &&
                      (types.supertype(owner().type).tsym == syms.enumSym)) {
                      // constructors of true enums are private
                      flags = PRIVATE | GENERATEDCONSTR;
                  } else {
                      flags = (owner().flags() & AccessFlags) | GENERATEDCONSTR;
                  }
                  constructorSymbol = new MethodSymbol(flags, names.init,
                      constructorType(), owner());
              }
              return constructorSymbol;
          }
  
          @Override
          public Type enclosingType() {
              return Type.noType;
      }
  
          @Override
          public TypeSymbol owner() {
              return owner;
          }
  
          @Override
          public List<Name> superArgs() {
              return List.nil();
              }
      }
  
      class AnonClassConstructorHelper extends BasicConstructorHelper {
  
          MethodSymbol constr;
          Type encl;
          boolean based = false;
  
          AnonClassConstructorHelper(TypeSymbol owner, MethodSymbol constr, JCExpression encl) {
              super(owner);
              this.constr = constr;
              this.encl = encl != null ? encl.type : Type.noType;
          }
  
          @Override
          public Type constructorType() {
              if (constructorType == null) {
                  Type ctype = types.memberType(owner.type, constr);
                  if (!enclosingType().hasTag(NONE)) {
                      ctype = types.createMethodTypeWithParameters(ctype, ctype.getParameterTypes().prepend(enclosingType()));
                      based = true;
                  }
                  constructorType = ctype;
              }
              return constructorType;
          }
  
          @Override
          public MethodSymbol constructorSymbol() {
              MethodSymbol csym = super.constructorSymbol();
              csym.flags_field |= ANONCONSTR | (constr.flags() & VARARGS);
              csym.flags_field |= based ? ANONCONSTR_BASED : 0;
              ListBuffer<VarSymbol> params = new ListBuffer<>();
              List<Type> argtypes = constructorType().getParameterTypes();
              if (!enclosingType().hasTag(NONE)) {
                  argtypes = argtypes.tail;
                  params = params.prepend(new VarSymbol(PARAMETER, make.paramName(0), enclosingType(), csym));
              }
              if (constr.params != null) {
                  for (VarSymbol p : constr.params) {
                      params.add(new VarSymbol(PARAMETER | p.flags(), p.name, argtypes.head, csym));
                      argtypes = argtypes.tail;
                  }
              }
              csym.params = params.toList();
              return csym;
          }
  
          @Override
          public Type enclosingType() {
              return encl;
          }
  
          @Override
          public List<Name> superArgs() {
              List<JCVariableDecl> params = make.Params(constructorType().getParameterTypes(), constructorSymbol());
              if (!enclosingType().hasTag(NONE)) {
                  params = params.tail;
              }
              return params.map(vd -> vd.name);
          }
      }
  
      class RecordConstructorHelper extends BasicConstructorHelper {
          boolean lastIsVarargs;
          List<JCVariableDecl> recordFieldDecls;
  
          RecordConstructorHelper(ClassSymbol owner, List<JCVariableDecl> recordFieldDecls) {
              super(owner);
              this.recordFieldDecls = recordFieldDecls;
              this.lastIsVarargs = owner.getRecordComponents().stream().anyMatch(rc -> rc.isVarargs());
          }
  
          @Override
          public Type constructorType() {
              if (constructorType == null) {
                  ListBuffer<Type> argtypes = new ListBuffer<>();
                  JCVariableDecl lastField = recordFieldDecls.last();
                  for (JCVariableDecl field : recordFieldDecls) {
                      argtypes.add(field == lastField && lastIsVarargs ? types.elemtype(field.sym.type) : field.sym.type);
                  }
  
                  constructorType = new MethodType(argtypes.toList(), syms.voidType, List.nil(), syms.methodClass);
              }
              return constructorType;
          }
  		
         @Override
          public MethodSymbol constructorSymbol() {
              MethodSymbol csym = super.constructorSymbol();
              /* if we have to generate a default constructor for records we will treat it as the compact one
               * to trigger field initialization later on
               */
              csym.flags_field |= Flags.COMPACT_RECORD_CONSTRUCTOR | GENERATEDCONSTR;
              ListBuffer<VarSymbol> params = new ListBuffer<>();
              JCVariableDecl lastField = recordFieldDecls.last();
              for (JCVariableDecl field : recordFieldDecls) {
                  params.add(new VarSymbol(
                          GENERATED_MEMBER | PARAMETER | RECORD | (field == lastField && lastIsVarargs ? Flags.VARARGS : 0),
                          field.name, field.sym.type, csym));
              }
              csym.params = params.toList();
              csym.flags_field |= RECORD;
              return csym;
          }
  
          @Override
          public JCMethodDecl finalAdjustment(JCMethodDecl md) {
              List<JCVariableDecl> tmpRecordFieldDecls = recordFieldDecls;
              for (JCVariableDecl arg : md.params) {
                  /* at this point we are passing all the annotations in the field to the corresponding
                   * parameter in the constructor.
                   */
                  RecordComponent rc = ((ClassSymbol) owner).getRecordComponent(arg.sym);
                  TreeCopier<JCTree> tc = new TreeCopier<JCTree>(make.at(arg.pos));
                  arg.mods.annotations = rc.getOriginalAnnos().isEmpty() ?
                          List.nil() :
                          tc.copy(rc.getOriginalAnnos());
                  arg.vartype = tc.copy(tmpRecordFieldDecls.head.vartype);
                  tmpRecordFieldDecls = tmpRecordFieldDecls.tail;
              }
              return md;
          }
      }
  
      JCTree defaultConstructor(TreeMaker make, DefaultConstructorHelper helper) {
          Type initType = helper.constructorType();
          MethodSymbol initSym = helper.constructorSymbol();
          ListBuffer<JCStatement> stats = new ListBuffer<>();
          if (helper.owner().type != syms.objectType) {
          JCExpression meth;
          if (!helper.enclosingType().hasTag(NONE)) {
          	meth = make.Select(make.Ident(initSym.params.head), names._super);
          } else {
              meth = make.Ident(names._super);
          }
              List<JCExpression> typeargs = initType.getTypeArguments().nonEmpty() ?
                      make.Types(initType.getTypeArguments()) : null;
              JCStatement superCall = make.Exec(make.Apply(typeargs, meth, helper.superArgs().map(make::Ident)));
              stats.add(superCall);
      }
          JCMethodDecl result = make.MethodDef(initSym, make.Block(0, stats.toList()));
          return helper.finalAdjustment(result);
      }
  /** Generate call to superclass constructor. This is:
       *
       *    super(id_0, ..., id_n)
       *
       * or, if based == true
       *
       *    id_0.super(id_1,...,id_n)
       *
       *  where id_0, ..., id_n are the names of the given parameters.
       *
       *  @param make    The tree factory
       *  @param params  The parameters that need to be passed to super
       *  @param typarams  The type parameters that need to be passed to super
       *  @param based   Is first parameter a this$n?
       */
      public JCExpressionStatement SuperCall(TreeMaker make,
                     List<Type> typarams,
                     List<JCVariableDecl> params,
                     boolean based) {
          JCExpression meth;
          if (based) {
              meth = make.Select(make.Ident(params.head), names._super);
              params = params.tail;
          } else {
              meth = make.Ident(names._super);
          }
          List<JCExpression> typeargs = typarams.nonEmpty() ? make.Types(typarams) : null;
          return make.Exec(make.Apply(typeargs, meth, make.Idents(params)));
      }
      
      /**
       * Mark sym deprecated if annotations contain @Deprecated annotation.
       */
      public void markDeprecated(Symbol sym, List<JCAnnotation> annotations, Env<AttrContext> env) {
          // In general, we cannot fully process annotations yet,  but we
          // can attribute the annotation types and then check to see if the
          // @Deprecated annotation is present.
          attr.attribAnnotationTypes(annotations, env);
          handleDeprecatedAnnotations(annotations, sym);
      }
  
      /**
       * If a list of annotations contains a reference to java.lang.Deprecated,
       * set the DEPRECATED flag.
       * If the annotation is marked forRemoval=true, also set DEPRECATED_REMOVAL.
       **/
      private void handleDeprecatedAnnotations(List<JCAnnotation> annotations, Symbol sym) {
          for (List<JCAnnotation> al = annotations; !al.isEmpty(); al = al.tail) {
              JCAnnotation a = al.head;
              if (a.annotationType.type == syms.deprecatedType) {
                  sym.flags_field |= (Flags.DEPRECATED | Flags.DEPRECATED_ANNOTATION);
                  setFlagIfAttributeTrue(a, sym, names.forRemoval, DEPRECATED_REMOVAL);
              } else if (a.annotationType.type == syms.previewFeatureType) {
                  sym.flags_field |= Flags.PREVIEW_API;
                  setFlagIfAttributeTrue(a, sym, names.reflective, Flags.PREVIEW_REFLECTIVE);
              }
          }
      }
      //where:
          private void setFlagIfAttributeTrue(JCAnnotation a, Symbol sym, Name attribute, long flag) {
              a.args.stream()
                      .filter(e -> e.hasTag(ASSIGN))
                      .map(e -> (JCAssign) e)
                      .filter(assign -> TreeInfo.name(assign.lhs) == attribute)
                      .findFirst()
                      .ifPresent(assign -> {
                          JCExpression rhs = TreeInfo.skipParens(assign.rhs);
                          if (rhs.hasTag(LITERAL)
                                  && Boolean.TRUE.equals(((JCLiteral) rhs).getValue())) {
                              sym.flags_field |= flag;
                          }
                      });
          }
  }
  