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