transinner.java

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      * Construct definition of an access constructor.
      *  @param pos        The source code position of the definition.
      *  @param constr     The private constructor.
      *  @param accessor   The access method for the constructor.
      */
    Tree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) {
        make.at(pos);
        MethodDef md = make.MethodDef(accessor, accessor.externalType(), null);
        Ident callee = make.Ident(names._this);
        callee.sym = constr;
        callee.type = constr.type;
        md.body = make.Block(0,
                List.make( make.Call(
                make.App(callee, make.Idents(md.params.reverse().tail.reverse())))));
        return md;
    }

    /**
      * A scope containing all free variable proxies for currently translated
      *  class, as well as its this$n symbol (if needed).
      *  Proxy scopes are nested in the same way classes are.
      *  Inside a constructor, proxies and any this$n symbol are duplicated
      *  in an additional innermost scope, where they represent the constructor
      *  parameters.
      */
    Scope proxies;

    /**
     * A stack containing the this$n field of the currently translated
     *  classes (if needed) in innermost first order.
     *  Inside a constructor, proxies and any this$n symbol are duplicated
     *  in an additional innermost scope, where they represent the constructor
     *  parameters.
     */
    List outerThisStack;

    /**
     * The name of a free variable proxy.
     */
    Name proxyName(Name name) {
        return names.fromString("val$" + name);
    }

    /**
      * Proxy definitions for all free variables in given list, in reverse order.
      *  @param pos        The source code position of the definition.
      *  @param freevars   The free variables.
      *  @param owner      The class in which the definitions go.
      */
    List freevarDefs(int pos, List freevars, Symbol owner) {
        long flags = FINAL | SYNTHETIC;
        if (owner.kind == TYP && target.ordinal < Target.JDK1_4_2.ordinal)
            flags |= PRIVATE;
        List defs = VarDef.emptyList;
        for (List l = freevars; l.nonEmpty(); l = l.tail) {
            VarSymbol v = (Symbol.VarSymbol) l.head;
            VarSymbol proxy =
                    new VarSymbol(flags, proxyName(v.name), v.erasure(), owner);
            proxies.enter(proxy);
            VarDef vd = make.at(pos).VarDef(proxy, null);
            vd.vartype = access(vd.vartype);
            defs = defs.prepend(vd);
        }
        return defs;
    }

    /**
      * The name of a this$n field
      *  @param target   The class referenced by the this$n field
      */
    Name outerThisName(Type target) {
        Type t = target.outer();
        int nestingLevel = 0;
        while (t.tag == CLASS) {
            t = t.outer();
            nestingLevel++;
        }
        return names.fromString("this$" + nestingLevel);
    }

    /**
      * Definition for this$n field.
      *  @param pos        The source code position of the definition.
      *  @param owner      The class in which the definition goes.
      */
    VarDef outerThisDef(int pos, Symbol owner) {
        long flags = FINAL | SYNTHETIC;
        if (owner.kind == TYP && target.ordinal < Target.JDK1_4_2.ordinal)
            flags |= PRIVATE;
        Type target = owner.enclClass().type.outer().erasure();
        VarSymbol outerThis =
                new VarSymbol(flags, outerThisName(target), target, owner);
        outerThisStack = outerThisStack.prepend(outerThis);
        VarDef vd = make.at(pos).VarDef(outerThis, null);
        vd.vartype = access(vd.vartype);
        return vd;
    }

    /**
      * Return a list of trees that load the free variables in given list,
      *  in reverse order.
      *  @param pos          The source code position to be used for the trees.
      *  @param freevars     The list of free variables.
      */
    List loadFreevars(int pos, List freevars) {
        List args = Tree.emptyList;
        for (List l = freevars; l.nonEmpty(); l = l.tail)
            args = args.prepend(loadFreevar(pos, (Symbol.VarSymbol) l.head));
        return args;
    }

    Tree loadFreevar(int pos, VarSymbol v) {
        return access(v, make.at(pos).Ident(v), null, false);
    }

    /**
      * Construct a tree simulating the expression <C.this>.
      *  @param pos           The source code position to be used for the tree.
      *  @param c             The qualifier class.
      */
    Tree makeThis(int pos, TypeSymbol c) {
        if (currentClass == c) {
            return make.at(pos).This(c.erasure());
        } else {
            return makeOuterThis(pos, c);
        }
    }

    /**
      * Construct a tree that represents the outer instance
      *  <C.this>. Never pick the current `this'.
      *  @param pos           The source code position to be used for the tree.
      *  @param c             The qualifier class.
      */
    Tree makeOuterThis(int pos, TypeSymbol c) {
        List ots = outerThisStack;
        if (ots.isEmpty()) {
            log.error(pos, "no.encl.instance.of.type.in.scope", c.toJava());
            assert false;
            return make.Ident(syms.nullConst);
        }
        VarSymbol ot = (Symbol.VarSymbol) ots.head;
        Tree tree = access(make.at(pos).Ident(ot));
        TypeSymbol otc = ot.type.tsym;
        while (otc != c) {
            do {
                ots = ots.tail;
                if (ots.isEmpty()) {
                    log.error(pos, "no.encl.instance.of.type.in.scope", c.toJava());
                    assert false;
                    return tree;
                }
                ot = (Symbol.VarSymbol) ots.head;
            } while (ot.owner != otc)
                ;
            if (otc.owner.kind != PCK && !otc.hasOuterInstance()) {
                chk.earlyRefError(pos, c);
                assert false;
                return make.Ident(syms.nullConst);
            }
            tree = access(make.at(pos).Select(tree, ot));
            otc = ot.type.tsym;
        }
        return tree;
    }

    /**
      * Construct a tree that represents the closest outer instance
      *  <C.this> such that the given symbol is a member of C.
      *  @param pos           The source code position to be used for the tree.
      *  @param sym           The accessed symbol.
      *  @param preciseMatch  should we accept a type that is a subtype of
      *                       sym's owner, even if it doesn't contain sym
      *                       due to hiding, overriding, or non-inheritance
      *                       due to protection?
      */
    Tree makeOwnerThis(int pos, Symbol sym, boolean preciseMatch) {
        Symbol c = sym.owner;
        if (preciseMatch ? sym.isMemberOf(currentClass) :
                currentClass.isSubClass(sym.owner)) {
            return make.at(pos).This(c.erasure());
        } else {
            List ots = outerThisStack;
            if (ots.isEmpty()) {
                log.error(pos, "no.encl.instance.of.type.in.scope", c.toJava());
                assert false;
                return make.Ident(syms.nullConst);
            }
            VarSymbol ot = (Symbol.VarSymbol) ots.head;
            Tree tree = access(make.at(pos).Ident(ot));
            TypeSymbol otc = ot.type.tsym;
            while (!(preciseMatch ? sym.isMemberOf(otc) :
                    otc.isSubClass(sym.owner))) {
                do {
                    ots = ots.tail;
                    if (ots.isEmpty()) {
                        log.error(pos, "no.encl.instance.of.type.in.scope",
                                c.toJava());
                        assert false;
                        return tree;
                    }
                    ot = (Symbol.VarSymbol) ots.head;
                } while (ot.owner != otc)
                    ;
                tree = access(make.at(pos).Select(tree, ot));
                otc = ot.type.tsym;
            }
            return tree;
        }
    }

    /**
      * Return tree simulating the the assignment <this.name = name>, where
      *  name is the name of a free variable.
      */
    Tree initField(int pos, Name name) {
        Scope.Entry e = proxies.lookup(name);
        Symbol rhs = e.sym;
        assert rhs.owner.kind == MTH;
        Symbol lhs = e.next().sym;
        assert rhs.owner.owner == lhs.owner;
        make.at(pos);
        return make.Exec(
                make.Assign(make.Select(make.This(lhs.owner.erasure()), lhs),
                make.Ident(rhs)).setType(lhs.erasure()));
    }

    /**
      * Return tree simulating the the assignment <this.this$n = this$n>.
      */
    Tree initOuterThis(int pos) {
        VarSymbol rhs = (Symbol.VarSymbol) outerThisStack.head;
        assert rhs.owner.kind == MTH;
        VarSymbol lhs = (Symbol.VarSymbol) outerThisStack.tail.head;
        assert rhs.owner.owner == lhs.owner;
        make.at(pos);
        return make.Exec(
                make.Assign(make.Select(make.This(lhs.owner.erasure()), lhs),
                make.Ident(rhs)).setType(lhs.erasure()));
    }

    /**
      * Return the symbol of a class to contain a cache of
      *  compiler-generated statics such as class$ and the
      *  $assertionsDisabled flag.  We create an anonymous nested class
      *  unless one exists and return its symbol.  However, for
      *  backward compatibility in 1.4 and earlier we use the
      *  top-level class.
      */
    private ClassSymbol outerCacheClass() {
        ClassSymbol clazz = outermostClassDef.sym;
        if ((clazz.flags() & INTERFACE) == 0 &&
                target.ordinal < Target.JDK1_4_2.ordinal)
            return clazz;
        Scope s = clazz.members();
        for (Scope.Entry e = s.elems; e != null; e = e.sibling)
            if (e.sym.kind == TYP && e.sym.name == names.empty &&
                    (e.sym.flags() & INTERFACE) == 0)
                return (ClassSymbol) e.sym;
        return makeEmptyClass(STATIC | SYNTHETIC, clazz);
    }

    /**
      * Return symbol for "class$" method. If there is no method definition
      *  for class$, construct one as follows:
      *
      *    class class$(String x0) {
      *      try {
      *        return Class.forName(x0);
      *      } catch (ClassNotFoundException x1) {
      *        throw new NoClassDefFoundError(x1.getMessage());
      *      }
      *    }
      */
    private MethodSymbol classDollarSym(int pos) {
        ClassSymbol outerCacheClass = outerCacheClass();
        MethodSymbol classDollarSym =
                (MethodSymbol) lookupSynthetic(names.classDollar,
                outerCacheClass.members());
        if (classDollarSym == null) {
            classDollarSym = new MethodSymbol(STATIC | SYNTHETIC, names.classDollar,
                    new MethodType(Type.emptyList.prepend(syms.stringType),
                    syms.classType, Type.emptyList, syms.methodClass),
                    outerCacheClass);
            enterSynthetic(pos, classDollarSym, outerCacheClass.members());
            MethodDef md = make.MethodDef(classDollarSym, null);
            try {
                md.body = classDollarSymBody(pos, md);
            } catch (CompletionFailure ex) {
                md.body = make.Block(0, Tree.emptyList);
                chk.completionError(pos, ex);
            }
            ClassDef outerCacheClassDef = classDef(outerCacheClass);
            outerCacheClassDef.defs = outerCacheClassDef.defs.prepend(md);
        }
        return classDollarSym;
    }

    /**
      * Generate code for class$(String name).
      */
    Block classDollarSymBody(int pos, MethodDef md) {
        MethodSymbol classDollarSym = md.sym;
        ClassSymbol outerCacheClass = (ClassSymbol) classDollarSym.owner;
        Tree returnResult;
        if (target.ordinal >= Target.JDK1_4_2.ordinal) {
            VarSymbol clsym =
                    new VarSymbol(STATIC | SYNTHETIC, names.fromString("cl$"),
                    syms.classLoaderType, outerCacheClass);
            enterSynthetic(pos, clsym, outerCacheClass.members());
            VarDef cldef = make.VarDef(clsym, null);
            ClassDef outerCacheClassDef = classDef(outerCacheClass);
            outerCacheClassDef.defs = outerCacheClassDef.defs.prepend(cldef);
            Tree newcache = make.NewArray(make.Type(outerCacheClass.type),
                    Tree.emptyList.prepend(
                    make.Literal(Type.INT, new Integer(0)).setType(syms.intType))
                    , null);
            newcache.type = new ArrayType(outerCacheClass.type, syms.arrayClass);
            Symbol forNameSym =
                    rs.resolveInternalMethod(make.pos, attrEnv, syms.classType,
                    names.forName,
                    Type.emptyList.prepend(syms.classLoaderType).prepend(
                    syms.booleanType).prepend(syms.stringType));
            Tree clvalue = make.Conditional( makeBinary(Tree.EQ, make.Ident(clsym),
                    make.Ident(syms.nullConst)),
                    make.Assign(make.Ident(clsym),
                    makeCall(
                    makeCall(makeCall(newcache, names.getClass, Tree.emptyList),
                    names.getComponentType, Tree.emptyList),
                    names.getClassLoader, Tree.emptyList)).setType(
                    syms.classLoaderType),
                    make.Ident(clsym)).setType(syms.classLoaderType);
            List args = Tree.emptyList.prepend(clvalue).prepend(
                    make.Ident(syms.falseConst)).prepend(
                    make.Ident(((Tree.VarDef) md.params.head).sym));
            returnResult = make.Block(0,
                    Tree.emptyList.prepend(
                    make.Call(make.App(make.Ident(forNameSym), args))));
        } else {
            Symbol forNameSym =
                    rs.resolveInternalMethod(make.pos, attrEnv, syms.classType,
                    names.forName, Type.emptyList.prepend(syms.stringType));
            returnResult = make.Block(0,
                    Tree.emptyList.prepend( make.Call(
                    make.App(make.QualIdent(forNameSym),
                    List.make(make.Ident(((Tree.VarDef) md.params.head).sym))))));
        }
        VarSymbol catchParam = new VarSymbol(0, make.paramName(1),
                syms.classNotFoundExceptionType, classDollarSym);
        Tree rethrow;
        if (target.ordinal >= Target.JDK1_4.ordinal) {
            Tree throwExpr = makeCall(
                    makeNewClass(syms.noClassDefFoundErrorType, Tree.emptyList),
                    names.initCause, Tree.emptyList.prepend(make.Ident(catchParam)));
            rethrow = make.Throw(throwExpr);
        } else {
            Symbol getMessageSym = rs.resolveInternalMethod(make.pos, attrEnv,
                    syms.classNotFoundExceptionType, names.getMessage,
                    Type.emptyList);