org.jfree.chart.entity.JFreeChartEntity Maven / Gradle / Ivy

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-present, by David Gilbert and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
 * Other names may be trademarks of their respective owners.]
 *
 * ---------------------
 * JFreeChartEntity.java
 * --------------------
 * (C) Copyright 2009-present, by David Gilbert and Contributors.
 *
 * Original Author:  Peter Kolb;
 * Contributor(s):   Tracy Hiltbrand (equals/hashCode comply with EqualsVerifier);
 *
 */

package org.jfree.chart.entity;

import java.awt.Shape;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Objects;

import org.jfree.chart.JFreeChart;
import org.jfree.chart.util.Args;
import org.jfree.chart.util.SerialUtils;

/**
 * A class that captures information about an entire chart.
 */
public class JFreeChartEntity extends ChartEntity {

    /** For serialization. */
    private static final long serialVersionUID = -4445994133561919083L;
            //same as for ChartEntity!

    /** The chart. */
    private JFreeChart chart;

    /**
     * Creates a new chart entity.
     *
     * @param area  the area ({@code null} not permitted).
     * @param chart  the chart ({@code null} not permitted).
     */
    public JFreeChartEntity(Shape area, JFreeChart chart) {
        // defer argument checks...
        this(area, chart, null);
    }

    /**
     * Creates a new chart entity.
     *
     * @param area  the area ({@code null} not permitted).
     * @param chart  the chart ({@code null} not permitted).
     * @param toolTipText  the tool tip text ({@code null} permitted).
     */
    public JFreeChartEntity(Shape area, JFreeChart chart, String toolTipText) {
        // defer argument checks...
        this(area, chart, toolTipText, null);
    }

    /**
     * Creates a new chart entity.
     *
     * @param area  the area ({@code null} not permitted).
     * @param chart  the chart ({@code null} not permitted).
     * @param toolTipText  the tool tip text ({@code null} permitted).
     * @param urlText  the URL text for HTML image maps ({@code null}
     *                 permitted).
     */
    public JFreeChartEntity(Shape area, JFreeChart chart, String toolTipText,
            String urlText) {
        super(area, toolTipText, urlText);
        Args.nullNotPermitted(chart, "chart");
        this.chart = chart;
    }

    /**
     * Returns the chart that occupies the entity area.
     *
     * @return The chart (never {@code null}).
     */
    public JFreeChart getChart() {
        return this.chart;
    }

    /**
     * Returns a string representation of the chart entity, useful for
     * debugging.
     *
     * @return A string.
     */
    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder("JFreeChartEntity: ");
        sb.append("tooltip = ");
        sb.append(getToolTipText());
        return sb.toString();
    }

    /**
     * Tests the entity for equality with an arbitrary object.
     *
     * @param obj  the object to test against ({@code null} permitted).
     *
     * @return A boolean.
     */
    @Override
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof JFreeChartEntity)) {
            return false;
        }
        JFreeChartEntity that = (JFreeChartEntity) obj;

        // fix the "equals not symmetric" problem
        if (!that.canEqual(this)) {
            return false;
        }
        if (!(Objects.equals(this.chart, that.chart))) {
            return false;
        }
        return super.equals(obj);
    }

    /**
     * Ensures symmetry between super/subclass implementations of equals. For
     * more detail, see http://jqno.nl/equalsverifier/manual/inheritance.
     *
     * @param other Object
     * 
     * @return true ONLY if the parameter is THIS class type
     */
    @Override
    public boolean canEqual(Object other) {
        // Solves Problem: equals not symmetric
        return (other instanceof JFreeChartEntity);
    }

    @Override
    public int hashCode() {
        int hash = super.hashCode(); // equals calls superclass function, so hashCode must also
        hash = 59 * hash + Objects.hashCode(this.chart);
        return hash;
    }

    /**
     * Returns a clone of the entity.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException if there is a problem cloning the
     *         entity.
     */
    @Override
    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the output stream.
     *
     * @throws IOException  if there is an I/O error.
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        stream.defaultWriteObject();
        SerialUtils.writeShape(getArea(), stream);
     }

    /**
     * Provides serialization support.
     *
     * @param stream  the input stream.
     *
     * @throws IOException  if there is an I/O error.
     * @throws ClassNotFoundException  if there is a classpath problem.
     */
    private void readObject(ObjectInputStream stream)
        throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        setArea(SerialUtils.readShape(stream));
    }

}