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/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2020, by Object Refinery Limited 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.]
*
* ----------
* Title.java
* ----------
* (C) Copyright 2000-2020, by David Berry and Contributors.
*
* Original Author: David Berry;
* Contributor(s): David Gilbert (for Object Refinery Limited);
* Nicolas Brodu;
*
* Changes (from 21-Aug-2001)
* --------------------------
* 21-Aug-2001 : Added standard header (DG);
* 18-Sep-2001 : Updated header (DG);
* 14-Nov-2001 : Package com.jrefinery.common.ui.* changed to
* com.jrefinery.ui.* (DG);
* 07-Feb-2002 : Changed blank space around title from Insets --> Spacer, to
* allow for relative or absolute spacing (DG);
* 25-Jun-2002 : Removed unnecessary imports (DG);
* 01-Oct-2002 : Fixed errors reported by Checkstyle (DG);
* 14-Oct-2002 : Changed the event listener storage structure (DG);
* 11-Sep-2003 : Took care of listeners while cloning (NB);
* 22-Sep-2003 : Spacer cannot be null. Added nullpointer checks for this (TM);
* 08-Jan-2003 : Renamed AbstractTitle --> Title and moved to separate
* package (DG);
* 26-Oct-2004 : Refactored to implement Block interface, and removed redundant
* constants (DG);
* 11-Jan-2005 : Removed deprecated code in preparation for the 1.0.0
* release (DG);
* 02-Feb-2005 : Changed Spacer --> RectangleInsets for padding (DG);
* 03-May-2005 : Fixed problem in equals() method (DG);
* 19-Sep-2008 : Added visibility flag (DG);
* 02-Jul-2013 : Use ParamChecks (DG);
*
*/
package org.jfree.chart.title;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import javax.swing.event.EventListenerList;
import org.jfree.chart.block.AbstractBlock;
import org.jfree.chart.block.Block;
import org.jfree.chart.event.TitleChangeEvent;
import org.jfree.chart.event.TitleChangeListener;
import org.jfree.chart.ui.HorizontalAlignment;
import org.jfree.chart.ui.RectangleEdge;
import org.jfree.chart.ui.RectangleInsets;
import org.jfree.chart.ui.VerticalAlignment;
import org.jfree.chart.util.ObjectUtils;
import org.jfree.chart.util.Args;
/**
* The base class for all chart titles. A chart can have multiple titles,
* appearing at the top, bottom, left or right of the chart.
*
* Concrete implementations of this class will render text and images, and
* hence do the actual work of drawing titles.
*/
public abstract class Title extends AbstractBlock
implements Block, Cloneable, Serializable {
/** For serialization. */
private static final long serialVersionUID = -6675162505277817221L;
/** The default title position. */
public static final RectangleEdge DEFAULT_POSITION = RectangleEdge.TOP;
/** The default horizontal alignment. */
public static final HorizontalAlignment
DEFAULT_HORIZONTAL_ALIGNMENT = HorizontalAlignment.CENTER;
/** The default vertical alignment. */
public static final VerticalAlignment
DEFAULT_VERTICAL_ALIGNMENT = VerticalAlignment.CENTER;
/** Default title padding. */
public static final RectangleInsets DEFAULT_PADDING = new RectangleInsets(
1, 1, 1, 1);
/**
* A flag that controls whether or not the title is visible.
*
* @since 1.0.11
*/
public boolean visible;
/** The title position. */
private RectangleEdge position;
/** The horizontal alignment of the title content. */
private HorizontalAlignment horizontalAlignment;
/** The vertical alignment of the title content. */
private VerticalAlignment verticalAlignment;
/** Storage for registered change listeners. */
private transient EventListenerList listenerList;
/**
* A flag that can be used to temporarily disable the listener mechanism.
*/
private boolean notify;
/**
* Creates a new title, using default attributes where necessary.
*/
protected Title() {
this(Title.DEFAULT_POSITION,
Title.DEFAULT_HORIZONTAL_ALIGNMENT,
Title.DEFAULT_VERTICAL_ALIGNMENT, Title.DEFAULT_PADDING);
}
/**
* Creates a new title, using default attributes where necessary.
*
* @param position the position of the title ({@code null} not
* permitted).
* @param horizontalAlignment the horizontal alignment of the title
* ({@code null} not permitted).
* @param verticalAlignment the vertical alignment of the title
* ({@code null} not permitted).
*/
protected Title(RectangleEdge position,
HorizontalAlignment horizontalAlignment,
VerticalAlignment verticalAlignment) {
this(position, horizontalAlignment, verticalAlignment,
Title.DEFAULT_PADDING);
}
/**
* Creates a new title.
*
* @param position the position of the title ({@code null} not
* permitted).
* @param horizontalAlignment the horizontal alignment of the title (LEFT,
* CENTER or RIGHT, {@code null} not
* permitted).
* @param verticalAlignment the vertical alignment of the title (TOP,
* MIDDLE or BOTTOM, {@code null} not
* permitted).
* @param padding the amount of space to leave around the outside of the
* title ({@code null} not permitted).
*/
protected Title(RectangleEdge position,
HorizontalAlignment horizontalAlignment,
VerticalAlignment verticalAlignment, RectangleInsets padding) {
Args.nullNotPermitted(position, "position");
Args.nullNotPermitted(horizontalAlignment, "horizontalAlignment");
Args.nullNotPermitted(verticalAlignment, "verticalAlignment");
Args.nullNotPermitted(padding, "padding");
this.visible = true;
this.position = position;
this.horizontalAlignment = horizontalAlignment;
this.verticalAlignment = verticalAlignment;
setPadding(padding);
this.listenerList = new EventListenerList();
this.notify = true;
}
/**
* Returns a flag that controls whether or not the title should be
* drawn. The default value is {@code true}.
*
* @return A boolean.
*
* @see #setVisible(boolean)
*
* @since 1.0.11
*/
public boolean isVisible() {
return this.visible;
}
/**
* Sets a flag that controls whether or not the title should be drawn, and
* sends a {@link TitleChangeEvent} to all registered listeners.
*
* @param visible the new flag value.
*
* @see #isVisible()
*
* @since 1.0.11
*/
public void setVisible(boolean visible) {
this.visible = visible;
notifyListeners(new TitleChangeEvent(this));
}
/**
* Returns the position of the title.
*
* @return The title position (never {@code null}).
*/
public RectangleEdge getPosition() {
return this.position;
}
/**
* Sets the position for the title and sends a {@link TitleChangeEvent} to
* all registered listeners.
*
* @param position the position ({@code null} not permitted).
*/
public void setPosition(RectangleEdge position) {
Args.nullNotPermitted(position, "position");
if (this.position != position) {
this.position = position;
notifyListeners(new TitleChangeEvent(this));
}
}
/**
* Returns the horizontal alignment of the title.
*
* @return The horizontal alignment (never {@code null}).
*/
public HorizontalAlignment getHorizontalAlignment() {
return this.horizontalAlignment;
}
/**
* Sets the horizontal alignment for the title and sends a
* {@link TitleChangeEvent} to all registered listeners.
*
* @param alignment the horizontal alignment ({@code null} not
* permitted).
*/
public void setHorizontalAlignment(HorizontalAlignment alignment) {
Args.nullNotPermitted(alignment, "alignment");
if (this.horizontalAlignment != alignment) {
this.horizontalAlignment = alignment;
notifyListeners(new TitleChangeEvent(this));
}
}
/**
* Returns the vertical alignment of the title.
*
* @return The vertical alignment (never {@code null}).
*/
public VerticalAlignment getVerticalAlignment() {
return this.verticalAlignment;
}
/**
* Sets the vertical alignment for the title, and notifies any registered
* listeners of the change.
*
* @param alignment the new vertical alignment (TOP, MIDDLE or BOTTOM,
* {@code null} not permitted).
*/
public void setVerticalAlignment(VerticalAlignment alignment) {
Args.nullNotPermitted(alignment, "alignment");
if (this.verticalAlignment != alignment) {
this.verticalAlignment = alignment;
notifyListeners(new TitleChangeEvent(this));
}
}
/**
* Returns the flag that indicates whether or not the notification
* mechanism is enabled.
*
* @return The flag.
*/
public boolean getNotify() {
return this.notify;
}
/**
* Sets the flag that indicates whether or not the notification mechanism
* is enabled. There are certain situations (such as cloning) where you
* want to turn notification off temporarily.
*
* @param flag the new value of the flag.
*/
public void setNotify(boolean flag) {
this.notify = flag;
if (flag) {
notifyListeners(new TitleChangeEvent(this));
}
}
/**
* Draws the title on a Java 2D graphics device (such as the screen or a
* printer).
*
* @param g2 the graphics device.
* @param area the area allocated for the title (subclasses should not
* draw outside this area).
*/
@Override
public abstract void draw(Graphics2D g2, Rectangle2D area);
/**
* Returns a clone of the title.
*
* One situation when this is useful is when editing the title properties -
* you can edit a clone, and then it is easier to cancel the changes if
* necessary.
*
* @return A clone of the title.
*
* @throws CloneNotSupportedException not thrown by this class, but it may
* be thrown by subclasses.
*/
@Override
public Object clone() throws CloneNotSupportedException {
Title duplicate = (Title) super.clone();
duplicate.listenerList = new EventListenerList();
// RectangleInsets is immutable => same reference in clone OK
return duplicate;
}
/**
* Registers an object for notification of changes to the title.
*
* @param listener the object that is being registered.
*/
public void addChangeListener(TitleChangeListener listener) {
this.listenerList.add(TitleChangeListener.class, listener);
}
/**
* Unregisters an object for notification of changes to the chart title.
*
* @param listener the object that is being unregistered.
*/
public void removeChangeListener(TitleChangeListener listener) {
this.listenerList.remove(TitleChangeListener.class, listener);
}
/**
* Notifies all registered listeners that the chart title has changed in
* some way.
*
* @param event an object that contains information about the change to
* the title.
*/
protected void notifyListeners(TitleChangeEvent event) {
if (this.notify) {
Object[] listeners = this.listenerList.getListenerList();
for (int i = listeners.length - 2; i >= 0; i -= 2) {
if (listeners[i] == TitleChangeListener.class) {
((TitleChangeListener) listeners[i + 1]).titleChanged(
event);
}
}
}
}
/**
* Tests an object for equality with this title.
*
* @param obj the object ({@code null} not permitted).
*
* @return {@code true} or {@code false}.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof Title)) {
return false;
}
Title that = (Title) obj;
if (this.visible != that.visible) {
return false;
}
if (this.position != that.position) {
return false;
}
if (this.horizontalAlignment != that.horizontalAlignment) {
return false;
}
if (this.verticalAlignment != that.verticalAlignment) {
return false;
}
if (this.notify != that.notify) {
return false;
}
return super.equals(obj);
}
/**
* Returns a hashcode for the title.
*
* @return The hashcode.
*/
@Override
public int hashCode() {
int result = 193;
result = 37 * result + ObjectUtils.hashCode(this.position);
result = 37 * result
+ ObjectUtils.hashCode(this.horizontalAlignment);
result = 37 * result + ObjectUtils.hashCode(this.verticalAlignment);
return result;
}
/**
* 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();
}
/**
* 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();
this.listenerList = new EventListenerList();
}
}