resolve.java

GJC（Generic Java Compiler）编译器

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

    /**
      * 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 parameters,
      *                   if we looked for a method.
      */
    Symbol access(Symbol sym, int pos, Type site, Name name, boolean qualified,
            List argtypes) {
        if (sym.kind >= AMBIGUOUS) {
            if (!site.isErroneous() && !Type.isErroneous(argtypes))
                ((ResolveError) sym).report(log, pos, site, name, argtypes);
            do {
                sym = ((ResolveError) sym).sym;
            } while (sym.kind >= AMBIGUOUS)
                ;
            if (sym == syms.errSymbol)
                sym = new ErrorType(name, qualified ? site.tsym : syms.noSymbol).tsym;
        }
        return sym;
    }

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

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

    /**
      * print all scopes starting with scope s and proceeding outwards.
      *  used for debugging.
      */
    public static 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;
        }
    }

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

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

    /**
      * Warn about an unchecked method invocation.
      */
    void warnUncheckedInvocation(int pos, Symbol sym, List argtypes) {
        if (sym.kind < AMBIGUOUS) {
            chk.warnUnchecked(pos, "unchecked.meth.invocation.applied",
                    sym.toJava(), sym.javaLocation(), Type.toJavaList(argtypes));
        }
    }

    /**
      * 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(int pos, Env 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 parameters.
      */
    Symbol resolveMethod(int pos, Env env, Name name, List argtypes) {
        Symbol sym = findFun(env, name, argtypes);
        if (sym.kind >= WRONG_MTHS && Type.isDerivedRaw(argtypes) &&
                !((AttrContext) env.info).rawArgs) {
            ((AttrContext) env.info).rawArgs = true;
            sym = findFun(env, name, argtypes);
            ((AttrContext) env.info).rawArgs = false;
            warnUncheckedInvocation(pos, sym, argtypes);
        }
        if (sym.kind >= AMBIGUOUS) {
            sym = access(sym, pos, env.enclClass.sym.type, name, false, argtypes);
        }
        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 parameters.
      */
    Symbol resolveQualifiedMethod(int pos, Env env, Type site, Name name,
            List argtypes) {
        Symbol sym = findMethod(env, site, name, argtypes);
        if (sym.kind >= WRONG_MTHS && Type.isDerivedRaw(argtypes) &&
                !((AttrContext) env.info).rawArgs) {
            ((AttrContext) env.info).rawArgs = true;
            sym = findMethod(env, site, name, argtypes);
            ((AttrContext) env.info).rawArgs = false;
            warnUncheckedInvocation(pos, sym, argtypes);
        }
        if (sym.kind >= AMBIGUOUS) {
            sym = access(sym, pos, site, name, true, argtypes);
        }
        return sym;
    }

    /**
      * Resolve a qualified method identifier, throw a fatal error if not
      *  found.
      *  @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 parameters.
      */
    Symbol resolveInternalMethod(int pos, Env env, Type site, Name name,
            List argtypes) {
        Symbol sym = resolveQualifiedMethod(pos, env, site, name, argtypes);
        if (sym.kind == MTH)
            return sym;
        else
            throw new FatalError( Log.getLocalizedString("fatal.err.cant.locate.meth",
                    name.toJava()));
    }

    /**
      * Resolve constructor.
      *  @param pos       The position to use for error reporting.
      *  @param env       The environment current at the constructor invocation.
      *  @param site      The type of class for which a constructor is searched.
      *  @param argtypes  The types of the constructor invocation's value
      *			 parameters.
      */
    Symbol resolveConstructor(int pos, Env env, Type site, List argtypes) {
        Symbol sym = resolveQualifiedMethod(pos, env, site, names.init, argtypes);
        if ((sym.flags() & DEPRECATED) != 0 &&
                (((AttrContext) env.info).scope.owner.flags() & DEPRECATED) ==
                0 && ((AttrContext) env.info).scope.owner.outermostClass() !=
                sym.outermostClass())
            chk.warnDeprecated(pos, sym);
        return sym;
    }

    /**
      * Resolve operator.
      *  @param pos       The position to use for error reporting.
      *  @param optag     The tag of the operation tree.
      *  @param env       The environment current at the operation.
      *  @param argtypes  The types of the operands.
      */
    Symbol resolveOperator(int pos, int optag, Env env, List argtypes) {
        Name name = treeinfo.operatorName(optag);
        return access(findMethod(env, syms.predefClass.type, name, argtypes),
                pos, env.enclClass.sym.type, name, false, argtypes);
    }

    /**
      * Resolve operator.
      *  @param pos       The position to use for error reporting.
      *  @param optag     The tag of the operation tree.
      *  @param env       The environment current at the operation.
      *  @param argtypes  The types of the operands.
      */
    Symbol resolveUnaryOperator(int pos, int optag, Env env, Type arg) {
        List argtypes = Type.emptyList.prepend(arg);
        return resolveOperator(pos, optag, env, argtypes);
    }

    /**
      * Resolve binary operator.
      *  @param pos       The position to use for error reporting.
      *  @param optag     The tag of the operation tree.
      *  @param env       The environment current at the operation.
      *  @param left      The types of the left operand.
      *  @param right     The types of the right operand.
      */
    Symbol resolveBinaryOperator(int pos, int optag, Env env, Type left, Type right) {
        List argtypes = Type.emptyList.prepend(right).prepend(left);
        return resolveOperator(pos, optag, env, argtypes);
    }

    /**
      * Resolve `c.name' where name == this or name == super.
      *  @param pos           The position to use for error reporting.
      *  @param env           The environment current at the expression.
      *  @param c             The qualifier.
      *  @param name          The identifier's name.
      */
    Symbol resolveSelf(int pos, Env env, TypeSymbol c, Name name) {
        Env env1 = env;
        boolean staticOnly = false;
        while (env1.outer != null) {
            if (isStatic(env1))
                staticOnly = true;
            if (env1.enclClass.sym == c) {
                Symbol sym = ((AttrContext) env1.info).scope.lookup(name).sym;
                if (sym != null) {
                    if (staticOnly)
                        sym = new StaticError(sym);
                    return access(sym, pos, env.enclClass.sym.type, name, true);
                }
            }
            if ((env1.enclClass.sym.flags() & STATIC) != 0)
                staticOnly = true;
            env1 = env1.outer;
        }
        log.error(pos, "not.encl.class", c.toJava());
        return syms.errSymbol;
    }

    /**
      * Resolve `c.this' for an enclosing class c that contains
      *  the named member.
      *  @param pos           The position to use for error reporting.
      *  @param env           The environment current at the expression.
      *  @param member        The member that must be contained in the result.
      */
    Symbol resolveSelfContaining(int pos, Env env, Symbol member) {
        Name name = names._this;
        Env env1 = env;
        boolean staticOnly = false;
        while (env1.outer != null) {
            if (isStatic(env1))
                staticOnly = true;
            if (env1.enclClass.sym.isSubClass(member.owner)) {
                Symbol sym = ((AttrContext) env1.info).scope.lookup(name).sym;
                if (sym != null) {
                    if (staticOnly)
                        sym = new StaticError(sym);
                    return access(sym, pos, env.enclClass.sym.type, name, true);
                }
            }
            if ((env1.enclClass.sym.flags() & STATIC) != 0)
                staticOnly = true;
            env1 = env1.outer;
        }
        log.error(pos, "encl.class.required", member.toJava());