hr.fer.spocc.lexer.action.SubactionFactory.java Source code

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Here is the source code for hr.fer.spocc.lexer.action.SubactionFactory.java

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/*
 * SubactionFactory.java
 *
 * Copyright (C) 2010 Leo Osvald <leo.osvald@gmail.com>
 *
 * This file is part of SPoCC.
 *
 * SPoCC is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * SPoCC 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with SPoCC. If not, see <http://www.gnu.org/licenses/>.
 */
package hr.fer.spocc.lexer.action;

import hr.fer.spocc.lexer.Subaction;
import hr.fer.spocc.lexer.SubactionType;

import java.util.EnumMap;
import java.util.Map;

import org.apache.commons.lang.Validate;

/**
 * Singleton factory za podakcije.
 * Trenutno su podrzane samo built-in podakcije.
 * 
 * @author Leo Osvald
 *
 */
public class SubactionFactory {

    private static final Map<SubactionType, Subaction> BUILTIN_ACTIONS = new EnumMap<SubactionType, Subaction>(
            SubactionType.class);

    public static synchronized Subaction getSubaction(SubactionType type) {
        Validate.notNull(type);
        Validate.isTrue(type.isBuiltIn());

        // check cache
        Subaction ret = BUILTIN_ACTIONS.get(type);
        if (ret != null) {
            return ret;
        }

        switch (type) {
        case ENTER_STATE:
            ret = new EnterStateSubaction();
            break;
        case NEW_LINE:
            ret = new NewLineSubaction();
            break;
        case TOKENIZE:
            ret = new TokenizeSubaction();
            break;
        case TOKENIZE_FIRST:
            ret = new TokenizeFirstSubaction();
            break;
        case SKIP:
            ret = new SkipSubaction();
            break;
        default:
            throw new UnsupportedOperationException("Custom subactions are not yet implemented");
        }

        // cache the action to avoid new object allocations
        BUILTIN_ACTIONS.put(type, ret);

        return ret;
    }
}