source: other-projects/rsyntax-textarea/src/java/org/fife/ui/rsyntaxtextarea/AbstractTokenMakerFactory.java@ 25584

/*
 * 12/14/08
 *
 * AbstractTokenMakerFactory.java - Base class for TokenMaker implementations.
 * 
 * This library is distributed under a modified BSD license.  See the included
 * RSyntaxTextArea.License.txt file for details.
 */
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);
    }


}