/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2007, 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.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ----------
* Title.java
* ----------
* (C) Copyright 2000-2007, 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);
*
*/
package com.positive.charts.title;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import javax.swing.event.EventListenerList;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.GCData;
import org.eclipse.swt.graphics.Rectangle;
import com.positive.charts.block.AbstractBlock;
import com.positive.charts.block.Block;
import com.positive.charts.block.RectangleInsets;
import com.positive.charts.common.RectangleEdge;
import com.positive.charts.data.util.ObjectUtilities;
import com.positive.charts.event.TitleChangeEvent;
import com.positive.charts.event.TitleChangeListener;
import com.positive.charts.util.HorizontalAlignment;
import com.positive.charts.util.VerticalAlignment;
/**
* The base class for all chart titles. A chart can have multiple titles,
* appearing at the top, bottom, left or right of the chart.
* <P>
* 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);
/** 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</code> not permitted).
* @param horizontalAlignment
* the horizontal alignment of the title (<code>null</code> not
* permitted).
* @param verticalAlignment
* the vertical alignment of the title (<code>null</code> not
* permitted).
*/
protected Title(final RectangleEdge position,
final HorizontalAlignment horizontalAlignment,
final VerticalAlignment verticalAlignment) {
this(position, horizontalAlignment, verticalAlignment,
Title.DEFAULT_PADDING);
}
/**
* Creates a new title.
*
* @param position
* the position of the title (<code>null</code> not permitted).
* @param horizontalAlignment
* the horizontal alignment of the title (LEFT, CENTER or RIGHT,
* <code>null</code> not permitted).
* @param verticalAlignment
* the vertical alignment of the title (TOP, MIDDLE or BOTTOM,
* <code>null</code> not permitted).
* @param padding
* the amount of space to leave around the outside of the title (
* <code>null</code> not permitted).
*/
protected Title(final RectangleEdge position,
final HorizontalAlignment horizontalAlignment,
final VerticalAlignment verticalAlignment,
final RectangleInsets padding) {
// check arguments...
if (position == null) {
throw new IllegalArgumentException("Null 'position' argument.");
}
if (horizontalAlignment == null) {
throw new IllegalArgumentException(
"Null 'horizontalAlignment' argument.");
}
if (verticalAlignment == null) {
throw new IllegalArgumentException(
"Null 'verticalAlignment' argument.");
}
if (padding == null) {
throw new IllegalArgumentException("Null 'spacer' argument.");
}
this.position = position;
this.horizontalAlignment = horizontalAlignment;
this.verticalAlignment = verticalAlignment;
this.setPadding(padding);
this.listenerList = new EventListenerList();
this.notify = true;
}
/**
* Registers an object for notification of changes to the title.
*
* @param listener
* the object that is being registered.
*/
public void addChangeListener(final TitleChangeListener listener) {
this.listenerList.add(TitleChangeListener.class, listener);
}
/**
* Returns a clone of the title.
* <P>
* 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.
*/
public Object clone() throws CloneNotSupportedException {
final Title duplicate = (Title) super.clone();
duplicate.listenerList = new EventListenerList();
// RectangleInsets is immutable => same reference in clone OK
return duplicate;
}
/**
* 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).
*/
public abstract void draw(GC g2, Rectangle area);
/**
* Tests an object for equality with this title.
*
* @param obj
* the object (<code>null</code> not permitted).
*
* @return <code>true</code> or <code>false</code>.
*/
public boolean equals(final Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof Title)) {
return false;
}
if (!super.equals(obj)) {
return false;
}
final Title that = (Title) obj;
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 true;
}
/**
* Returns the horizontal alignment of the title.
*
* @return The horizontal alignment (never <code>null</code>).
*/
public HorizontalAlignment getHorizontalAlignment() {
return this.horizontalAlignment;
}
/**
* Returns the flag that indicates whether or not the notification mechanism
* is enabled.
*
* @return The flag.
*/
public boolean getNotify() {
return this.notify;
}
/**
* Returns the position of the title.
*
* @return The title position (never <code>null</code>).
*/
public RectangleEdge getPosition() {
return this.position;
}
/**
* Returns the vertical alignment of the title.
*
* @return The vertical alignment (never <code>null</code>).
*/
public VerticalAlignment getVerticalAlignment() {
return this.verticalAlignment;
}
/**
* Returns a hashcode for the title.
*
* @return The hashcode.
*/
public int hashCode() {
int result = 193;
result = 37 * result + ObjectUtilities.hashCode(this.position);
result = 37 * result
+ ObjectUtilities.hashCode(this.horizontalAlignment);
result = 37 * result + ObjectUtilities.hashCode(this.verticalAlignment);
return result;
}
public void internal_dispose_GC(final int handle, final GCData data) {
}
public int internal_new_GC(final GCData data) {
return 0;
}
/**
* 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(final TitleChangeEvent event) {
if (this.notify) {
final 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);
}
}
}
}
/**
* 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(final ObjectInputStream stream) throws IOException,
ClassNotFoundException {
stream.defaultReadObject();
this.listenerList = new EventListenerList();
}
/**
* Unregisters an object for notification of changes to the chart title.
*
* @param listener
* the object that is being unregistered.
*/
public void removeChangeListener(final TitleChangeListener listener) {
this.listenerList.remove(TitleChangeListener.class, listener);
}
/**
* Sets the horizontal alignment for the title and sends a
* {@link TitleChangeEvent} to all registered listeners.
*
* @param alignment
* the horizontal alignment (<code>null</code> not permitted).
*/
public void setHorizontalAlignment(final HorizontalAlignment alignment) {
if (alignment == null) {
throw new IllegalArgumentException("Null 'alignment' argument.");
}
if (this.horizontalAlignment != alignment) {
this.horizontalAlignment = alignment;
this.notifyListeners(new TitleChangeEvent(this));
}
}
/**
* 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(final boolean flag) {
this.notify = flag;
if (flag) {
this.notifyListeners(new TitleChangeEvent(this));
}
}
/**
* Sets the position for the title and sends a {@link TitleChangeEvent} to
* all registered listeners.
*
* @param position
* the position (<code>null</code> not permitted).
*/
public void setPosition(final RectangleEdge position) {
if (position == null) {
throw new IllegalArgumentException("Null 'position' argument.");
}
if (this.position != position) {
this.position = position;
this.notifyListeners(new TitleChangeEvent(this));
}
}
/**
* 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</code> not permitted).
*/
public void setVerticalAlignment(final VerticalAlignment alignment) {
if (alignment == null) {
throw new IllegalArgumentException("Null 'alignment' argument.");
}
if (this.verticalAlignment != alignment) {
this.verticalAlignment = alignment;
this.notifyListeners(new TitleChangeEvent(this));
}
}
/**
* Provides serialization support.
*
* @param stream
* the output stream.
*
* @throws IOException
* if there is an I/O error.
*/
private void writeObject(final ObjectOutputStream stream)
throws IOException {
stream.defaultWriteObject();
}
}