enter.java

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    Type classEnter(JCTree tree, Env<AttrContext> env) {
	Env<AttrContext> prevEnv = this.env;
	try {
	    this.env = env;
	    tree.accept(this);
	    return result;
	}  catch (CompletionFailure ex) {
	    return chk.completionError(tree.pos(), ex);
	} finally {
	    this.env = prevEnv;
	}
    }

    /** Visitor method: enter classes of a list of trees, returning a list of types.
     */
    <T extends JCTree> List<Type> classEnter(List<T> trees, Env<AttrContext> env) {
	ListBuffer<Type> ts = new ListBuffer<Type>();
	for (List<T> l = trees; l.nonEmpty(); l = l.tail)
	    ts.append(classEnter(l.head, env));
	return ts.toList();
    }

    public void visitTopLevel(JCCompilationUnit tree) {
	JavaFileObject prev = log.useSource(tree.sourcefile);
        boolean addEnv = false;
	boolean isPkgInfo = tree.sourcefile.isNameCompatible("package-info",
							     JavaFileObject.Kind.SOURCE);
	if (tree.pid != null) {
	    tree.packge = reader.enterPackage(TreeInfo.fullName(tree.pid));
	    if (tree.packageAnnotations.nonEmpty()) {
                if (isPkgInfo) {
                    addEnv = true;
                } else {
                    log.error(tree.packageAnnotations.head.pos(),
                              "pkg.annotations.sb.in.package-info.java");
                }
	    }
	} else {
	    tree.packge = syms.unnamedPackage;
	}
	tree.packge.complete(); // Find all classes in package.
        Env<AttrContext> env = topLevelEnv(tree);

	// Save environment of package-info.java file.
	if (isPkgInfo) {
	    Env<AttrContext> env0 = typeEnvs.get(tree.packge);
	    if (env0 == null) {
		typeEnvs.put(tree.packge, env);
	    } else {
		JCCompilationUnit tree0 = env0.toplevel;
                if (!fileManager.isSameFile(tree.sourcefile, tree0.sourcefile)) {
		    log.warning(tree.pid != null ? tree.pid.pos()
						 : null,
				"pkg-info.already.seen",
				tree.packge);
		    if (addEnv || (tree0.packageAnnotations.isEmpty() &&
				   tree.docComments != null &&
				   tree.docComments.get(tree) != null)) {
			typeEnvs.put(tree.packge, env);
		    }
		}
	    }
	}
	classEnter(tree.defs, env);
        if (addEnv) {
            todo.append(env);
        }
	log.useSource(prev);
	result = null;
    }

    public void visitClassDef(JCClassDecl tree) {
	Symbol owner = env.info.scope.owner;
	Scope enclScope = enterScope(env);
	ClassSymbol c;
	if (owner.kind == PCK) {
	    // We are seeing a toplevel class.
	    PackageSymbol packge = (PackageSymbol)owner;
	    for (Symbol q = packge; q != null && q.kind == PCK; q = q.owner)
		q.flags_field |= EXISTS;
	    c = reader.enterClass(tree.name, packge);
	    packge.members().enterIfAbsent(c);
	    if ((tree.mods.flags & PUBLIC) != 0 && !classNameMatchesFileName(c, env)) {
		log.error(tree.pos(),
			  "class.public.should.be.in.file", tree.name);
	    }
	} else {
	    if (tree.name.len != 0 &&
		!chk.checkUniqueClassName(tree.pos(), tree.name, enclScope)) {
		result = null;
		return;
	    }
	    if (owner.kind == TYP) {
		// We are seeing a member class.
		c = reader.enterClass(tree.name, (TypeSymbol)owner);
		if ((owner.flags_field & INTERFACE) != 0) {
		    tree.mods.flags |= PUBLIC | STATIC;
		}
	    } else {
		// We are seeing a local class.
		c = reader.defineClass(tree.name, owner);
		c.flatname = chk.localClassName(c);
		if (c.name.len != 0)
		    chk.checkTransparentClass(tree.pos(), c, env.info.scope);
	    }
	}
	tree.sym = c;

	// Enter class into `compiled' table and enclosing scope.
	if (chk.compiled.get(c.flatname) != null) {
	    duplicateClass(tree.pos(), c);
	    result = new ErrorType(tree.name, (TypeSymbol)owner);
	    tree.sym = (ClassSymbol)result.tsym;
	    return;
	}
	chk.compiled.put(c.flatname, c);
	enclScope.enter(c);

	// Set up an environment for class block and store in `typeEnvs'
	// table, to be retrieved later in memberEnter and attribution.
	Env<AttrContext> localEnv = classEnv(tree, env);
	typeEnvs.put(c, localEnv);

	// Fill out class fields.
	c.completer = memberEnter;
	c.flags_field = chk.checkFlags(tree.pos(), tree.mods.flags, c, tree);
	c.sourcefile = env.toplevel.sourcefile;
	c.members_field = new Scope(c);

	ClassType ct = (ClassType)c.type;
	if (owner.kind != PCK && (c.flags_field & STATIC) == 0) {
	    // We are seeing a local or inner class.
	    // Set outer_field of this class to closest enclosing class
	    // which contains this class in a non-static context
	    // (its "enclosing instance class"), provided such a class exists.
	    Symbol owner1 = owner;
	    while ((owner1.kind & (VAR | MTH)) != 0 &&
		   (owner1.flags_field & STATIC) == 0) {
		owner1 = owner1.owner;
	    }
	    if (owner1.kind == TYP) {
		ct.setEnclosingType(owner1.type);
	    }
	}

	// Enter type parameters.
	ct.typarams_field = classEnter(tree.typarams, localEnv);

	// Add non-local class to uncompleted, to make sure it will be
	// completed later.
	if (!c.isLocal() && uncompleted != null) uncompleted.append(c);
//	System.err.println("entering " + c.fullname + " in " + c.owner);//DEBUG

	// Recursively enter all member classes.
	classEnter(tree.defs, localEnv);

	result = c.type;
    }
    //where
	/** Does class have the same name as the file it appears in?
	 */
	private static boolean classNameMatchesFileName(ClassSymbol c,
							Env<AttrContext> env) {
	    return env.toplevel.sourcefile.isNameCompatible(c.name.toString(),
							    JavaFileObject.Kind.SOURCE);
	}

    /** Complain about a duplicate class. */
    protected void duplicateClass(DiagnosticPosition pos, ClassSymbol c) {
	log.error(pos, "duplicate.class", c.fullname);
    }

    /** Class enter visitor method for type parameters.
     *	Enter a symbol for type parameter in local scope, after checking that it
     *	is unique.
     */
    public void visitTypeParameter(JCTypeParameter tree) {
	TypeVar a = (tree.type != null)
	    ? (TypeVar)tree.type
	    : new TypeVar(tree.name, env.info.scope.owner, syms.botType);
	tree.type = a;
	if (chk.checkUnique(tree.pos(), a.tsym, env.info.scope)) {
	    env.info.scope.enter(a.tsym);
	}
	result = a;
    }

    /** Default class enter visitor method: do nothing.
     */
    public void visitTree(JCTree tree) {
	result = null;
    }

    /** Main method: enter all classes in a list of toplevel trees.
     *	@param trees	  The list of trees to be processed.
     */
    public void main(List<JCCompilationUnit> trees) {
	complete(trees, null);
    }

    /** Main method: enter one class from a list of toplevel trees and
     *  place the rest on uncompleted for later processing.
     *  @param trees      The list of trees to be processed.
     *  @param c          The class symbol to be processed.
     */
    public void complete(List<JCCompilationUnit> trees, ClassSymbol c) {
        annotate.enterStart();
	ListBuffer<ClassSymbol> prevUncompleted = uncompleted;
	if (memberEnter.completionEnabled) uncompleted = new ListBuffer<ClassSymbol>();

	try {
	    // enter all classes, and construct uncompleted list
	    classEnter(trees, null);

	    // complete all uncompleted classes in memberEnter
	    if  (memberEnter.completionEnabled) {
		while (uncompleted.nonEmpty()) {
		    ClassSymbol clazz = uncompleted.next();
		    if (c == null || c == clazz || prevUncompleted == null)
			clazz.complete();
		    else
			// defer
			prevUncompleted.append(clazz);
		}

		// 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.elems == null) {
			JavaFileObject prev = log.useSource(tree.sourcefile);
			Env<AttrContext> env = typeEnvs.get(tree);
			if (env == null)
			    env = topLevelEnv(tree);
			memberEnter.memberEnter(tree, env);
			log.useSource(prev);
		    }
		}
	    }
	} finally {
	    uncompleted = prevUncompleted;
            annotate.enterDone();
	}
    }
}