Package diva.canvas

Class FigureDecorator

java.lang.Object

diva.canvas.AbstractFigure

diva.canvas.AbstractFigureContainer

diva.canvas.FigureDecorator

All Implemented Interfaces:

CanvasComponent, Figure, FigureContainer, FigureSet, VisibleComponent, UserObjectContainer

Direct Known Subclasses:

BasicEdgeHighlighter, BasicHighlighter, Manipulator, TypedDecorator

public abstract class FigureDecorator
extends AbstractFigureContainer

A FigureDecorator is a figure container that contains a single child figure. The purpose of a FigureDecorator is to change or affect the way in which the child is rendered, and so this class behaves somewhat differently to other figures.

This class is a reasonable example of the Decorator design pattern, hence its name.

Version:

$Id$

Author:

John Reekie

Pt.AcceptedRating:

Red

Constructor Summary

Constructors

Constructor	Description
FigureDecorator()

Method Summary

Modifier and Type	Method	Description
void	add(Figure f)	Add a figure.
boolean	contains(Figure f)	Test if the given figure is the one contained by this decorator.
java.util.Iterator	figures()	Return an iteration containing the one child.
java.util.Iterator	figuresFromBack()	Return an iteration containing the one child.
java.util.Iterator	figuresFromFront()	Return an iteration containing the one child.
java.awt.geom.Rectangle2D	getBounds()	Get the bounds of this figure, which is by default the same as the child figure, if there is one, or a very small rectangle if there isn't.
Figure	getChild()	Get the child figure, or null if there isn't one.
FigureContainer	getContainer()	Get the container, which is defined as the lowest ancestor that is not a FigureDecorator.
Figure	getDecoratedFigure()	Get the decorated figure, which is defined as the highest descendent that is not a decorator.
int	getFigureCount()	Return zero if there is no child, or one if there is.
java.awt.Shape	getShape()	Get the outline shape of this figure, which is by default the same as the child figure, if there is one, or a very small rectangle if there isn't.
boolean	hit(java.awt.geom.Rectangle2D r)	Test if the child is hit.
abstract FigureDecorator	newInstance(Figure f)	Create a new instance of this figure decorator, modeled on this one.
void	paint(java.awt.Graphics2D g)	Paint the figure.
void	remove(Figure f)	Remove a figure.
protected void	replaceChild(Figure child, Figure replacement)	Replace the first figure, which must be a child, with the second, which must not be a child.
void	setChild(Figure f)	Set the child figure.
void	transform(java.awt.geom.AffineTransform at)	Transform the figure with the supplied transform.
void	translate(double x, double y)	Translate the figure by the given distance.

Methods inherited from class diva.canvas.AbstractFigureContainer

decorate, pick, pick, repaint, undecorate

Methods inherited from class diva.canvas.AbstractFigure

contains, getInteractor, getLayer, getOrigin, getParent, getToolTipText, getTransformContext, getUserObject, intersects, isVisible, paint, repaint, setInteractor, setParent, setToolTipText, setUserObject, setVisible

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface diva.canvas.CanvasComponent

getTransformContext, repaint

Methods inherited from interface diva.canvas.VisibleComponent

isVisible, paint, setVisible

Constructor Detail

FigureDecorator

public FigureDecorator()

Method Detail

add

public void add(Figure f)

Add a figure. This method does not make too much sense for Decorators, but has to be here anyway. This method is set same as calling setChild(f).

Parameters:

f - The figure to be added.

contains

public boolean contains(Figure f)

Test if the given figure is the one contained by this decorator.

Specified by:

contains in interface FigureContainer

Specified by:

contains in interface FigureSet

Specified by:

contains in class AbstractFigureContainer

Parameters:

f - The figure to be searched for

Returns:

true if the figure is contained.

figures

public java.util.Iterator figures()

Return an iteration containing the one child.

Specified by:

figures in interface FigureSet

Specified by:

figures in class AbstractFigureContainer

Returns:

The iterator.

figuresFromBack

public java.util.Iterator figuresFromBack()

Return an iteration containing the one child.

Specified by:

figuresFromBack in interface FigureSet

Specified by:

figuresFromBack in class AbstractFigureContainer

Returns:

The iterator

figuresFromFront

public java.util.Iterator figuresFromFront()

Return an iteration containing the one child.

Specified by:

figuresFromFront in interface FigureSet

Specified by:

figuresFromFront in class AbstractFigureContainer

Returns:

The iterator

getBounds

public java.awt.geom.Rectangle2D getBounds()

Get the bounds of this figure, which is by default the same as the child figure, if there is one, or a very small rectangle if there isn't.

Specified by:

getBounds in interface Figure

Overrides:

getBounds in class AbstractFigure

Returns:

the bounding box of this figure.

getChild

public Figure getChild()

Get the child figure, or null if there isn't one.

Returns:

The child figure

getContainer

public FigureContainer getContainer()

Get the container, which is defined as the lowest ancestor that is not a FigureDecorator.

Returns:

the container

getDecoratedFigure

public Figure getDecoratedFigure()

Get the decorated figure, which is defined as the highest descendent that is not a decorator.

Returns:

The decorated figure.

getFigureCount

public int getFigureCount()

Return zero if there is no child, or one if there is.

Specified by:

getFigureCount in interface FigureContainer

Specified by:

getFigureCount in class AbstractFigureContainer

Returns:

The number of figures.

getShape

public java.awt.Shape getShape()

Get the outline shape of this figure, which is by default the same as the child figure, if there is one, or a very small rectangle if there isn't.

Specified by:

getShape in interface Figure

Specified by:

getShape in class AbstractFigure

Returns:

the outline shape of this figure

hit

public boolean hit(java.awt.geom.Rectangle2D r)

Test if the child is hit.

Specified by:

hit in interface Figure

Overrides:

hit in class AbstractFigure

Parameters:

r - The rectangle to be checked.

Returns:

true if the figure is hit by the given rectangle.

newInstance

public abstract FigureDecorator newInstance(Figure f)

Create a new instance of this figure decorator, modeled on this one. This is used by interaction code that needs to dynamically create new manipulators. The figure argument can be used by this method to initialize the new instance; however, the new instance must not be wrapped around the figure, since that should be done by the caller.

Parameters:

f - The figure

Returns:

The new instance of the figure decorator.

paint

public void paint(java.awt.Graphics2D g)

Paint the figure. By default, this method simply forwards the paint request to the contained figure.

Specified by:

paint in interface VisibleComponent

Overrides:

paint in class AbstractFigureContainer

Parameters:

g - The Graphics context

setChild

public void setChild(Figure f)

Set the child figure. If there is already a child figure, remove it from this container.

Parameters:

f - The child figure.

remove

public void remove(Figure f)

Remove a figure. This method does not make too much sense for Decorators, but has to be here anyway. If the passed figure is the same as the child figure, then this method is the same as calling setChild(null). Otherwise, it does nothing.

Parameters:

f - The figure to be removed

replaceChild

protected void replaceChild(Figure child,
                            Figure replacement)

Replace the first figure, which must be a child, with the second, which must not be a child.

Specified by:

replaceChild in class AbstractFigureContainer

Parameters:

child - The figure to be replaced.

replacement - The replacement figure.

transform

public void transform(java.awt.geom.AffineTransform at)

Transform the figure with the supplied transform. By default, this method simply forwards the paint request to the child figure.

Specified by:

transform in interface Figure

Overrides:

transform in class AbstractFigureContainer

Parameters:

at - The transform to be used.

translate

public void translate(double x,
                      double y)

Translate the figure by the given distance. By default, this method simply forwards the paint request to the child figure.

Specified by:

translate in interface Figure

Overrides:

translate in class AbstractFigureContainer

Parameters:

x - The x value to be moved.

y - The y value to be moved.