001 /*
002 * Copyright 2002-2008 Sun Microsystems, Inc. All Rights Reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation. Sun designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Sun in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022 * CA 95054 USA or visit www.sun.com if you need additional information or
023 * have any questions.
024 */
025
026 package com.sun.tools.javac.parser;
027
028 import com.sun.tools.javac.util.Context;
029 import com.sun.tools.javac.util.Log;
030 import com.sun.tools.javac.util.Name;
031 import com.sun.tools.javac.util.Names;
032
033 import static com.sun.tools.javac.parser.Token.*;
034
035 /**
036 * Map from Name to Token and Token to String.
037 *
038 * <p><b>This is NOT part of any API supported by Sun Microsystems.
039 * If you write code that depends on this, you do so at your own risk.
040 * This code and its internal interfaces are subject to change or
041 * deletion without notice.</b>
042 */
043 public class Keywords {
044 public static final Context.Key<Keywords> keywordsKey =
045 new Context.Key<Keywords>();
046
047 public static Keywords instance(Context context) {
048 Keywords instance = context.get(keywordsKey);
049 if (instance == null)
050 instance = new Keywords(context);
051 return instance;
052 }
053
054 private final Log log;
055 private final Names names;
056
057 protected Keywords(Context context) {
058 context.put(keywordsKey, this);
059 log = Log.instance(context);
060 names = Names.instance(context);
061
062 for (Token t : Token.values()) {
063 if (t.name != null)
064 enterKeyword(t.name, t);
065 else
066 tokenName[t.ordinal()] = null;
067 }
068
069 key = new Token[maxKey+1];
070 for (int i = 0; i <= maxKey; i++) key[i] = IDENTIFIER;
071 for (Token t : Token.values()) {
072 if (t.name != null)
073 key[tokenName[t.ordinal()].getIndex()] = t;
074 }
075 }
076
077
078 public Token key(Name name) {
079 return (name.getIndex() > maxKey) ? IDENTIFIER : key[name.getIndex()];
080 }
081
082 /**
083 * Keyword array. Maps name indices to Token.
084 */
085 private final Token[] key;
086
087 /** The number of the last entered keyword.
088 */
089 private int maxKey = 0;
090
091 /** The names of all tokens.
092 */
093 private Name[] tokenName = new Name[Token.values().length];
094
095 private void enterKeyword(String s, Token token) {
096 Name n = names.fromString(s);
097 tokenName[token.ordinal()] = n;
098 if (n.getIndex() > maxKey) maxKey = n.getIndex();
099 }
100 }