memberenter.java

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        return false;
    }


    /** Enter a set of annotations. */
    private void enterAnnotations(List<JCAnnotation> annotations,
                          Env<AttrContext> env,
                          Symbol s) {
        ListBuffer<Attribute.Compound> buf =
            new ListBuffer<Attribute.Compound>();
        Set<TypeSymbol> annotated = new HashSet<TypeSymbol>();
        if (!skipAnnotations)
        for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
            JCAnnotation a = al.head;
            Attribute.Compound c = annotate.enterAnnotation(a,
                                                            syms.annotationType,
                                                            env);
            if (c == null) continue;
            buf.append(c);
            // Note: @Deprecated has no effect on local variables and parameters
            if (!c.type.isErroneous()
                && s.owner.kind != MTH
                && types.isSameType(c.type, syms.deprecatedType))
                s.flags_field |= Flags.DEPRECATED;
            if (!annotated.add(a.type.tsym))
                log.error(a.pos, "duplicate.annotation");
        }
        s.attributes_field = buf.toList();
    }

    /** Queue processing of an attribute default value. */
    void annotateDefaultValueLater(final JCExpression defaultValue,
                                   final Env<AttrContext> localEnv,
                                   final MethodSymbol m) {
        annotate.later(new Annotate.Annotator() {
                public String toString() {
                    return "annotate " + m.owner + "." +
                        m + " default " + defaultValue;
                }
                public void enterAnnotation() {
                    JavaFileObject prev = log.useSource(localEnv.toplevel.sourcefile);
                    try {
                        enterDefaultValue(defaultValue, localEnv, m);
                    } finally {
                        log.useSource(prev);
                    }
                }
            });
    }

    /** Enter a default value for an attribute method. */
    private void enterDefaultValue(final JCExpression defaultValue,
                                   final Env<AttrContext> localEnv,
                                   final MethodSymbol m) {
        m.defaultValue = annotate.enterAttributeValue(m.type.getReturnType(),
                                                      defaultValue,
                                                      localEnv);
    }

/* ********************************************************************
 * Source completer
 *********************************************************************/

    /** Complete entering a class.
     *  @param sym         The symbol of the class to be completed.
     */
    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 (sym.flags() & Flags.COMPOUND) == 0;
            sym.completer = this;
            return;
        }

        ClassSymbol c = (ClassSymbol)sym;
        ClassType ct = (ClassType)c.type;
        Env<AttrContext> env = enter.typeEnvs.get(c);
        JCClassDecl tree = (JCClassDecl)env.tree;
        boolean wasFirst = isFirst;
        isFirst = false;

        JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
        try {
            // Save class environment for later member enter (2) processing.
            halfcompleted.append(env);

            // If this is a toplevel-class, make sure any preceding import
            // clauses have been seen.
            if (c.owner.kind == PCK) {
                memberEnter(env.toplevel, env.enclosing(JCTree.TOPLEVEL));
                todo.append(env);
            }

            // Mark class as not yet attributed.
            c.flags_field |= UNATTRIBUTED;

            if (c.owner.kind == TYP)
                c.owner.complete();

            // create an environment for evaluating the base clauses
            Env<AttrContext> baseEnv = baseEnv(tree, env);

            // Determine supertype.
            Type supertype =
                (tree.extending != null)
                ? attr.attribBase(tree.extending, baseEnv, true, false, true)
                : ((tree.mods.flags & Flags.ENUM) != 0 && !target.compilerBootstrap(c))
                ? attr.attribBase(enumBase(tree.pos, c), baseEnv,
                                  true, false, false)
                : (c.fullname == names.java_lang_Object)
                ? Type.noType
                : syms.objectType;
            ct.supertype_field = supertype;

            // Determine interfaces.
            ListBuffer<Type> interfaces = new ListBuffer<Type>();
            Set<Type> interfaceSet = new HashSet<Type>();
            List<JCExpression> interfaceTrees = tree.implementing;
            if ((tree.mods.flags & Flags.ENUM) != 0 && target.compilerBootstrap(c)) {
                // add interface Comparable<T>
                interfaceTrees =
                    interfaceTrees.prepend(make.Type(new ClassType(syms.comparableType.getEnclosingType(),
                                                                   List.of(c.type),
                                                                   syms.comparableType.tsym)));
                // add interface Serializable
                interfaceTrees =
                    interfaceTrees.prepend(make.Type(syms.serializableType));
            }
            for (JCExpression iface : interfaceTrees) {
                Type i = attr.attribBase(iface, baseEnv, false, true, true);
                if (i.tag == CLASS) {
                    interfaces.append(i);
                    chk.checkNotRepeated(iface.pos(), types.erasure(i), interfaceSet);
                }
            }
            if ((c.flags_field & ANNOTATION) != 0)
                ct.interfaces_field = List.of(syms.annotationType);
            else
                ct.interfaces_field = interfaces.toList();

            if (c.fullname == names.java_lang_Object) {
                if (tree.extending != null) {
                    chk.checkNonCyclic(tree.extending.pos(),
                                       supertype);
                    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();
                }
            }

            // Annotations.
            // 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(tree.mods.annotations, baseEnv);
            if (hasDeprecatedAnnotation(tree.mods.annotations))
                c.flags_field |= DEPRECATED;
            annotateLater(tree.mods.annotations, baseEnv, c);

            attr.attribTypeVariables(tree.typarams, baseEnv);

            chk.checkNonCyclic(tree.pos(), c.type);

            // Add default constructor if needed.
            if ((c.flags() & INTERFACE) == 0 &&
                !TreeInfo.hasConstructors(tree.defs)) {
                List<Type> argtypes = List.nil();
                List<Type> typarams = List.nil();
                List<Type> thrown = List.nil();
                long ctorFlags = 0;
                boolean based = false;
                if (c.name.len == 0) {
                    JCNewClass nc = (JCNewClass)env.next.tree;
                    if (nc.constructor != null) {
                        Type superConstrType = types.memberType(c.type,
                                                                nc.constructor);
                        argtypes = superConstrType.getParameterTypes();
                        typarams = superConstrType.getTypeArguments();
                        ctorFlags = nc.constructor.flags() & VARARGS;
                        if (nc.encl != null) {
                            argtypes = argtypes.prepend(nc.encl.type);
                            based = true;
                        }
                        thrown = superConstrType.getThrownTypes();
                    }
                }
                JCTree constrDef = DefaultConstructor(make.at(tree.pos), c,
                                                    typarams, argtypes, thrown,
                                                    ctorFlags, based);
                tree.defs = tree.defs.prepend(constrDef);
            }

            // If this is a class, enter symbols for this and super into
            // current scope.
            if ((c.flags_field & INTERFACE) == 0) {
                VarSymbol thisSym =
                    new VarSymbol(FINAL | HASINIT, names._this, c.type, c);
                thisSym.pos = Position.FIRSTPOS;
                env.info.scope.enter(thisSym);
                if (ct.supertype_field.tag == CLASS) {
                    VarSymbol superSym =
                        new VarSymbol(FINAL | HASINIT, names._super,
                                      ct.supertype_field, c);
                    superSym.pos = Position.FIRSTPOS;
                    env.info.scope.enter(superSym);
                }
            }

            // 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 &&
                c.owner.kind == PCK && c.owner != syms.unnamedPackage &&
                reader.packageExists(c.fullname))
                {
                    log.error(tree.pos, "clash.with.pkg.of.same.name", c);
                }

        } catch (CompletionFailure ex) {
            chk.completionError(tree.pos(), ex);
        } finally {
            log.useSource(prev);
        }

        // Enter all member fields and methods of a set of half completed
        // classes in a second phase.
        if (wasFirst) {
            try {
                while (halfcompleted.nonEmpty()) {
                    finish(halfcompleted.next());
                }
            } finally {
                isFirst = true;
            }

            // commit pending annotations
            annotate.flush();
        }
    }

    private Env<AttrContext> baseEnv(JCClassDecl tree, Env<AttrContext> env) {
        Scope typaramScope = new Scope(tree.sym);
        if (tree.typarams != null)
            for (List<JCTypeParameter> typarams = tree.typarams;
                 typarams.nonEmpty();
                 typarams = typarams.tail)
                typaramScope.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(typaramScope));
        localEnv.baseClause = true;
        localEnv.outer = outer;
        localEnv.info.isSelfCall = false;
        return localEnv;
    }

    /** Enter member fields and methods of a class
     *  @param env        the environment current for the class block.
     */
    private void finish(Env<AttrContext> env) {
        JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
        try {
            JCClassDecl tree = (JCClassDecl)env.tree;
            finishClass(tree, env);
        } finally {
            log.useSource(prev);
        }
    }

    /** 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
     */
    private JCExpression enumBase(int pos, ClassSymbol c) {
        JCExpression result = make.at(pos).
            TypeApply(make.QualIdent(syms.enumSym),
                      List.<JCExpression>of(make.Type(c.type)));
        return result;
    }

/* ***************************************************************************
 * tree building
 ****************************************************************************/

    /** Generate default constructor for given class. For classes different
     *  from java.lang.Object, this is:
     *
     *    c(argtype_0 x_0, ..., argtype_n x_n) throws thrown {
     *      super(x_0, ..., x_n)
     *    }
     *
     *  or, if based == true:
     *
     *    c(argtype_0 x_0, ..., argtype_n x_n) throws thrown {
     *      x_0.super(x_1, ..., x_n)
     *    }
     *
     *  @param make     The tree factory.
     *  @param c        The class owning the default constructor.
     *  @param argtypes The parameter types of the constructor.
     *  @param thrown   The thrown exceptions of the constructor.
     *  @param based    Is first parameter a this$n?
     */
    JCTree DefaultConstructor(TreeMaker make,
                            ClassSymbol c,
                            List<Type> typarams,
                            List<Type> argtypes,
                            List<Type> thrown,
                            long flags,
                            boolean based) {
        List<JCVariableDecl> params = make.Params(argtypes, syms.noSymbol);
        List<JCStatement> stats = List.nil();
        if (c.type != syms.objectType)
            stats = stats.prepend(SuperCall(make, typarams, params, based));
        if ((c.flags() & ENUM) != 0 &&
            (types.supertype(c.type).tsym == syms.enumSym ||
             target.compilerBootstrap(c))) {
            // constructors of true enums are private
            flags = (flags & ~AccessFlags) | PRIVATE | GENERATEDCONSTR;
        } else
            flags |= (c.flags() & AccessFlags) | GENERATEDCONSTR;
        if (c.name.len == 0) flags |= ANONCONSTR;
        JCTree result = make.MethodDef(
            make.Modifiers(flags),
            names.init,
            null,
            make.TypeParams(typarams),
            params,
            make.Types(thrown),
            make.Block(0, stats),
            null);
        return 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?
     */
    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)));
    }
}