src/antidote/org/apache/tools/ant/gui/core/EventToActionMapper.java

/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999, 2000 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Ant", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
package org.apache.tools.ant.gui.core;
import java.util.*;

/**
 * The purpose of this class is to manage the 
 * mappings between event type and action enabled state.
 * 
 * @version $Revision$ 
 * @author Simeon Fitch 
 */
class EventToActionMapper {

    /** Lookup for enable(true) events. Key is event type, value is
     *  a list of actions that are changed by the event. */
    private Map _enableOn = new HashMap();
    /** Lookup for enable(false) events. Key is event type, value is
     *  a list of actions that are changed by the event. */
    private Map _disableOn = new HashMap();


	/** 
	 * Defaul ctor.
	 * 
	 */
    public EventToActionMapper() {
    }

	/** 
	 * Add an action.
	 * 
	 * @param action Action to add.
	 */
    public void addAction(AntAction action) {
        putAction(action, action.getEnableOnEvents(), _enableOn);
        putAction(action, action.getDisableOnEvents(), _disableOn);
    }

	/** 
	 * For the given action store it in the event type mapping
     * for each of the given types.
	 * 
	 * @param action Action to store.
	 * @param clazzes Array of types to store it under.
	 * @param storage The place to store the association.
	 */
    private void putAction(AntAction action, Class[] clazzes, Map storage) {
        if(clazzes == null) return;

        for(int i = 0; i < clazzes.length; i++) {
            List values = (List) storage.get(clazzes[i]);
            if(values == null) {
                values = new ArrayList(1);
                storage.put(clazzes[i], values);
            }

            values.add(action);
        }
    }
	/** 
	 * For the given event change the state of any actions that 
     * have been registered as needing a transition as a result of
     * the event.
	 * 
	 * @param event The event to apply.
	 */
    public void applyEvent(EventObject event) {
        if(event == null) return;

        List vals = null;

        vals = (List) _enableOn.get(event.getClass());
        changeState(vals, true);

        vals = (List) _disableOn.get(event.getClass());
        changeState(vals, false);
    }

	/** 
	 * Set the enabled state of the given actions.
	 * 
	 * @param actions List of AntActions to set state for.
	 * @param state The state to set them to.
	 */
    private void changeState(List actions, boolean state) {
        if(actions == null) return;

        for(int i = 0, len = actions.size(); i < len; i++) {
            AntAction action = (AntAction) actions.get(i);
            action.setEnabled(state);
        }
    }
}