2362N/A * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved. 0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 0N/A * This code is free software; you can redistribute it and/or modify it 0N/A * under the terms of the GNU General Public License version 2 only, as 2362N/A * published by the Free Software Foundation. Oracle designates this 0N/A * particular file as subject to the "Classpath" exception as provided 2362N/A * by Oracle in the LICENSE file that accompanied this code. 0N/A * This code is distributed in the hope that it will be useful, but WITHOUT 0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 0N/A * version 2 for more details (a copy is included in the LICENSE file that 0N/A * accompanied this code). 0N/A * You should have received a copy of the GNU General Public License version 0N/A * 2 along with this work; if not, write to the Free Software Foundation, 0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2362N/A * or visit www.oracle.com if you need additional information or have any 0N/A * This class is used to provide enclosing scopes for top level classes. 0N/A * We cannot use <tt>null</tt> to represent such a scope, since the 0N/A * enclosing scope is computed lazily, and so the field storing it is 0N/A * null until it has been computed. Therefore, <tt>null</tt> is reserved 0N/A * to represent an as-yet-uncomputed scope, and cannot be used for any 0N/A * other kind of scope. 0N/A // Caches the unique instance of this class; instances contain no data 0N/A // so we can use the singleton pattern 0N/A // constructor is private to enforce use of factory method 0N/A * Factory method. Enforces the singleton pattern - only one 0N/A * instance of this class ever exists. 0N/A * Lookup a type variable in the scope, using its name. Always returns 0N/A * @param name - the name of the type variable being looked up