DatabaseStateDispatcher.java

/*******************************************************************************
 * Copyright (c) 2004, 2010 BREDEX GmbH.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     BREDEX GmbH - initial API and implementation and/or initial documentation
 *******************************************************************************/
package org.eclipse.jubula.client.core.utils;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

/**
 * @author BREDEX GmbH
 * @created Nov 17, 2006
 */
public class DatabaseStateDispatcher {
    /**
     * gui listener for showing connection window
     */
    private static Set<IDatabaseStateListener> listener;

    /**
     * Private utility constructor.
     */
    private DatabaseStateDispatcher() {
        // do nothing
    }

    /**
     * Adds a new progress listener to progress listener list.
     * 
     * @param l
     *            The progressListener to add.
     */
    public static void addDatabaseStateListener(IDatabaseStateListener l) {
        getListeners().add(l);
    }

    /**
     * Removes a new progress listener from progress listener list.
     * 
     * @param l
     *            The progressListener to remove.
     */
    public static void removeDatabaseStateListener(IDatabaseStateListener l) {
        getListeners().remove(l);
    }

    /**
     * Notifies all progressListeners of the progress listener list and calls
     * <code>progressListener.reactOnProgressEvent(ProgressEvent e)</code>
     * 
     * @param e
     *            the progressEvent
     */
    public static void notifyListener(DatabaseStateEvent e) {
        Iterator<IDatabaseStateListener> iter = getListeners().iterator();
        while (iter.hasNext()) {
            IDatabaseStateListener progressListener = iter.next();
            if (progressListener != null) {
                progressListener.reactOnDatabaseEvent(e);
            } else {
                if (listener != null) {
                    listener.remove(progressListener);
                }
            }
        }
    }

    /**
     * @return Set<IProgressListener>
     */
    private static Set<IDatabaseStateListener> getListeners() {
        if (listener == null) {
            listener = new HashSet<IDatabaseStateListener>();
        }
        return listener;
    }
}