AbstractTokenMakerFactory.java

/*
 * 12/14/08
 *
 * AbstractTokenMakerFactory.java - Base class for TokenMaker implementations.
 * Copyright (C) 2008 Robert Futrell
 * robert_futrell at users.sourceforge.net
 * http://fifesoft.com/rsyntaxtextarea
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA.
 */
package org.fife.ui.rsyntaxtextarea;

import java.util.Map;
import java.util.Set;

/**
 * Base class for {@link TokenMakerFactory} implementations. A <code>java.util.Map</code> maps keys to the names of
 * {@link TokenMaker} classes.
 * 
 * @author Robert Futrell
 * @version 1.0
 */
public abstract class AbstractTokenMakerFactory extends TokenMakerFactory {

    /**
     * A mapping from keys to the names of {@link TokenMaker} implementation class names. When
     * {@link #getTokenMaker(String)} is called with a key defined in this map, a <code>TokenMaker</code> of the
     * corresponding type is returned.
     */
    private Map tokenMakerMap;

    /**
     * Constructor.
     */
    protected AbstractTokenMakerFactory() {
        tokenMakerMap = createTokenMakerKeyToClassNameMap();
    }

    /**
     * Creates and returns a mapping from keys to the names of {@link TokenMaker} implementation classes. When
     * {@link #getTokenMaker(String)} is called with a key defined in this map, a <code>TokenMaker</code> of the
     * corresponding type is returned.
     * 
     * @return The map.
     */
    protected abstract Map createTokenMakerKeyToClassNameMap();

    /**
     * Returns a {@link TokenMaker} for the specified key.
     * 
     * @param key
     *            The key.
     * @return The corresponding <code>TokenMaker</code>, or <code>null</code> if none matches the specified key.
     */
    protected TokenMaker getTokenMakerImpl(String key) {
        String clazz = (String) tokenMakerMap.get(key);
        if (clazz != null) {
            try {
                return (TokenMaker) Class.forName(clazz).newInstance();
            } catch (RuntimeException re) { // FindBugs
                throw re;
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return null;
    }

    /**
     * {@inheritDoc}
     */
    public Set keySet() {
        return tokenMakerMap.keySet();
    }

    /**
     * Adds a mapping from a key to a <code>TokenMaker</code> implementation class name.
     * 
     * @param key
     *            The key.
     * @param className
     *            The <code>TokenMaker</code> class name.
     * @return The previous value for the specified key, or <code>null</code> if there was none.
     */
    public String putMapping(String key, String className) {
        return (String) tokenMakerMap.put(key, className);
    }

}