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 * Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package org.graalvm.visualvm.lib.ui.charts;

import java.util.Collection;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 *
 * @author Jiri Sedlacek
 */
public abstract class AbstractBarChartModel implements BarChartModel {
    //~ Instance fields ----------------------------------------------------------------------------------------------------------

    private Collection<ChartModelListener> listeners = new CopyOnWriteArraySet<>(); // Data change listeners

    //~ Constructors -------------------------------------------------------------------------------------------------------------

    /** Creates a new instance of AbstractBarChartModel */
    public AbstractBarChartModel() {
    }

    //~ Methods ------------------------------------------------------------------------------------------------------------------

    public abstract String getXAxisDesc();

    // --- Abstract BarChartModel ------------------------------------------------
    public abstract String[] getXLabels();

    public abstract String getYAxisDesc();

    public abstract int[] getYValues();

    // ---------------------------------------------------------------------------

    // --- Listeners -------------------------------------------------------------

    /**
     * Adds new ChartModel listener.
     * @param listener ChartModel listener to add
     */
    public synchronized void addChartModelListener(ChartModelListener listener) {
        listeners.add(listener);
    }

    /**
     * Removes ChartModel listener.
     * @param listener ChartModel listener to remove
     */
    public synchronized void removeChartModelListener(ChartModelListener listener) {
        listeners.remove(listener);
    }

    /**
     * Notifies all listeners about the data change.
     */
    protected void fireChartDataChanged() {
        for(ChartModelListener l : listeners) {
            l.chartDataChanged();
        }
    }

    // ---------------------------------------------------------------------------
}
