/*
 * Copyright 1999-2012 Alibaba Group.
 *  
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *  
 *      http://www.apache.org/licenses/LICENSE-2.0
 *  
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/**
 * Project: fastjson
 * 
 * File Created at 2010-12-2
 * 
 * Copyright 1999-2100 Alibaba.com Corporation Limited.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information of
 * Alibaba Company. ("Confidential Information").  You shall not
 * disclose such Confidential Information and shall use it only in
 * accordance with the terms of the license agreement you entered into
 * with Alibaba.com.
 */
package com.alibaba.cobar.parser.recognizer.mysql.lexer;

import java.util.HashMap;
import java.util.Map;

import com.alibaba.cobar.parser.recognizer.mysql.MySQLToken;

/**
 * @author <a href="mailto:shuo.qius@alibaba-inc.com">QIU Shuo</a>
 */
class MySQLKeywords {
    public static final MySQLKeywords DEFAULT_KEYWORDS = new MySQLKeywords();

    private final Map<String, MySQLToken> keywords = new HashMap<String, MySQLToken>(230);

    private MySQLKeywords() {
        for (MySQLToken type : MySQLToken.class.getEnumConstants()) {
            String name = type.name();
            if (name.startsWith("KW_")) {
                String kw = name.substring("KW_".length());
                keywords.put(kw, type);
            }
        }
        keywords.put("NULL", MySQLToken.LITERAL_NULL);
        keywords.put("FALSE", MySQLToken.LITERAL_BOOL_FALSE);
        keywords.put("TRUE", MySQLToken.LITERAL_BOOL_TRUE);
    }

    /**
     * @param keyUpperCase must be uppercase
     * @return <code>KeyWord</code> or {@link MySQLToken#LITERAL_NULL NULL} or
     *         {@link MySQLToken#LITERAL_BOOL_FALSE FALSE} or
     *         {@link MySQLToken#LITERAL_BOOL_TRUE TRUE}
     */
    public MySQLToken getKeyword(String keyUpperCase) {
        return keywords.get(keyUpperCase);
    }

}