resolve.java

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        Symbol bestSoFar = typeNotFound;
        for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
            Symbol sym = loadClass(env, e.sym.flatName());
            if (bestSoFar.kind == TYP && sym.kind == TYP &&
                bestSoFar != sym)
                return new AmbiguityError(bestSoFar, sym);
            else if (sym.kind < bestSoFar.kind)
                bestSoFar = sym;
        }
        return bestSoFar;
    }

    /** Find an unqualified type symbol.
     *  @param env       The current environment.
     *  @param name      The type's name.
     */
    Symbol findType(Env<AttrContext> env, Name name) {
        Symbol bestSoFar = typeNotFound;
        Symbol sym;
        boolean staticOnly = false;
        for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
            if (isStatic(env1)) staticOnly = true;
            for (Scope.Entry e = env1.info.scope.lookup(name);
                 e.scope != null;
                 e = e.next()) {
                if (e.sym.kind == TYP) {
                    if (staticOnly &&
                        e.sym.type.tag == TYPEVAR &&
                        e.sym.owner.kind == TYP) return new StaticError(e.sym);
                    return e.sym;
                }
            }

            sym = findMemberType(env1, env1.enclClass.sym.type, name,
                                 env1.enclClass.sym);
            if (staticOnly && sym.kind == TYP &&
                sym.type.tag == CLASS &&
                sym.type.getEnclosingType().tag == CLASS &&
                env1.enclClass.sym.type.isParameterized() &&
                sym.type.getEnclosingType().isParameterized())
                return new StaticError(sym);
            else if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;

            JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
            if ((encl.sym.flags() & STATIC) != 0)
                staticOnly = true;
        }

        if (env.tree.getTag() != JCTree.IMPORT) {
            sym = findGlobalType(env, env.toplevel.namedImportScope, name);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;

            sym = findGlobalType(env, env.toplevel.packge.members(), name);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;

            sym = findGlobalType(env, env.toplevel.starImportScope, name);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
        }

        return bestSoFar;
    }

    /** Find an unqualified identifier which matches a specified kind set.
     *  @param env       The current environment.
     *  @param name      The indentifier's name.
     *  @param kind      Indicates the possible symbol kinds
     *                   (a subset of VAL, TYP, PCK).
     */
    Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
        Symbol bestSoFar = typeNotFound;
        Symbol sym;

        if ((kind & VAR) != 0) {
            sym = findVar(env, name);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
        }

        if ((kind & TYP) != 0) {
            sym = findType(env, name);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
        }

        if ((kind & PCK) != 0) return reader.enterPackage(name);
        else return bestSoFar;
    }

    /** Find an identifier in a package which matches a specified kind set.
     *  @param env       The current environment.
     *  @param name      The identifier's name.
     *  @param kind      Indicates the possible symbol kinds
     *                   (a nonempty subset of TYP, PCK).
     */
    Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
                              Name name, int kind) {
        Name fullname = TypeSymbol.formFullName(name, pck);
        Symbol bestSoFar = typeNotFound;
        PackageSymbol pack = null;
        if ((kind & PCK) != 0) {
            pack = reader.enterPackage(fullname);
            if (pack.exists()) return pack;
        }
        if ((kind & TYP) != 0) {
            Symbol sym = loadClass(env, fullname);
            if (sym.exists()) {
                // don't allow programs to use flatnames
                if (name == sym.name) return sym;
            }
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
        }
        return (pack != null) ? pack : bestSoFar;
    }

    /** Find an identifier among the members of a given type `site'.
     *  @param env       The current environment.
     *  @param site      The type containing the symbol to be found.
     *  @param name      The identifier's name.
     *  @param kind      Indicates the possible symbol kinds
     *                   (a subset of VAL, TYP).
     */
    Symbol findIdentInType(Env<AttrContext> env, Type site,
                           Name name, int kind) {
        Symbol bestSoFar = typeNotFound;
        Symbol sym;
        if ((kind & VAR) != 0) {
            sym = findField(env, site, name, site.tsym);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
        }

        if ((kind & TYP) != 0) {
            sym = findMemberType(env, site, name, site.tsym);
            if (sym.exists()) return sym;
            else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
        }
        return bestSoFar;
    }

/* ***************************************************************************
 *  Access checking
 *  The following methods convert ResolveErrors to ErrorSymbols, issuing
 *  an error message in the process
 ****************************************************************************/

    /** If `sym' is a bad symbol: report error and return errSymbol
     *  else pass through unchanged,
     *  additional arguments duplicate what has been used in trying to find the
     *  symbol (--> flyweight pattern). This improves performance since we
     *  expect misses to happen frequently.
     *
     *  @param sym       The symbol that was found, or a ResolveError.
     *  @param pos       The position to use for error reporting.
     *  @param site      The original type from where the selection took place.
     *  @param name      The symbol's name.
     *  @param argtypes  The invocation's value arguments,
     *                   if we looked for a method.
     *  @param typeargtypes  The invocation's type arguments,
     *                   if we looked for a method.
     */
    Symbol access(Symbol sym,
                  DiagnosticPosition pos,
                  Type site,
                  Name name,
                  boolean qualified,
                  List<Type> argtypes,
                  List<Type> typeargtypes) {
        if (sym.kind >= AMBIGUOUS) {
//          printscopes(site.tsym.members());//DEBUG
            if (!site.isErroneous() &&
                !Type.isErroneous(argtypes) &&
                (typeargtypes==null || !Type.isErroneous(typeargtypes)))
                ((ResolveError)sym).report(log, pos, site, name, argtypes, typeargtypes);
            do {
                sym = ((ResolveError)sym).sym;
            } while (sym.kind >= AMBIGUOUS);
            if (sym == syms.errSymbol // preserve the symbol name through errors
                || ((sym.kind & ERRONEOUS) == 0 // make sure an error symbol is returned
                    && (sym.kind & TYP) != 0))
                sym = new ErrorType(name, qualified?site.tsym:syms.noSymbol).tsym;
        }
        return sym;
    }

    /** Same as above, but without type arguments and arguments.
     */
    Symbol access(Symbol sym,
                  DiagnosticPosition pos,
                  Type site,
                  Name name,
                  boolean qualified) {
        if (sym.kind >= AMBIGUOUS)
            return access(sym, pos, site, name, qualified, List.<Type>nil(), null);
        else
            return sym;
    }

    /** Check that sym is not an abstract method.
     */
    void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
        if ((sym.flags() & ABSTRACT) != 0)
            log.error(pos, "abstract.cant.be.accessed.directly",
                      kindName(sym), sym, sym.location());
    }

/* ***************************************************************************
 *  Debugging
 ****************************************************************************/

    /** print all scopes starting with scope s and proceeding outwards.
     *  used for debugging.
     */
    public void printscopes(Scope s) {
        while (s != null) {
            if (s.owner != null)
                System.err.print(s.owner + ": ");
            for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
                if ((e.sym.flags() & ABSTRACT) != 0)
                    System.err.print("abstract ");
                System.err.print(e.sym + " ");
            }
            System.err.println();
            s = s.next;
        }
    }

    void printscopes(Env<AttrContext> env) {
        while (env.outer != null) {
            System.err.println("------------------------------");
            printscopes(env.info.scope);
            env = env.outer;
        }
    }

    public void printscopes(Type t) {
        while (t.tag == CLASS) {
            printscopes(t.tsym.members());
            t = types.supertype(t);
        }
    }

/* ***************************************************************************
 *  Name resolution
 *  Naming conventions are as for symbol lookup
 *  Unlike the find... methods these methods will report access errors
 ****************************************************************************/

    /** Resolve an unqualified (non-method) identifier.
     *  @param pos       The position to use for error reporting.
     *  @param env       The environment current at the identifier use.
     *  @param name      The identifier's name.
     *  @param kind      The set of admissible symbol kinds for the identifier.
     */
    Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
                        Name name, int kind) {
        return access(
            findIdent(env, name, kind),
            pos, env.enclClass.sym.type, name, false);
    }

    /** Resolve an unqualified method identifier.
     *  @param pos       The position to use for error reporting.
     *  @param env       The environment current at the method invocation.
     *  @param name      The identifier's name.
     *  @param argtypes  The types of the invocation's value arguments.
     *  @param typeargtypes  The types of the invocation's type arguments.
     */
    Symbol resolveMethod(DiagnosticPosition pos,
                         Env<AttrContext> env,
                         Name name,
                         List<Type> argtypes,
                         List<Type> typeargtypes) {
        Symbol sym = findFun(env, name, argtypes, typeargtypes, false, env.info.varArgs=false);
        if (varargsEnabled && sym.kind >= WRONG_MTHS) {
            sym = findFun(env, name, argtypes, typeargtypes, true, false);
            if (sym.kind >= WRONG_MTHS)
                sym = findFun(env, name, argtypes, typeargtypes, true, env.info.varArgs=true);
        }
        if (sym.kind >= AMBIGUOUS) {
            sym = access(
                sym, pos, env.enclClass.sym.type, name, false, argtypes, typeargtypes);
        }
        return sym;
    }

    /** Resolve a qualified method identifier
     *  @param pos       The position to use for error reporting.
     *  @param env       The environment current at the method invocation.
     *  @param site      The type of the qualifying expression, in which
     *                   identifier is searched.
     *  @param name      The identifier's name.
     *  @param argtypes  The types of the invocation's value arguments.
     *  @param typeargtypes  The types of the invocation's type arguments.
     */
    Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
                                  Type site, Name name, List<Type> argtypes,
                                  List<Type> typeargtypes) {
        Symbol sym = findMethod(env, site, name, argtypes, typeargtypes, false,
                                env.info.varArgs=false, false);
        if (varargsEnabled && sym.kind >= WRONG_MTHS) {