ballworld.model

Class Ball

java.lang.Object

ballworld.model.Ball

All Implemented Interfaces:

java.util.Observer

public class Ball
extends java.lang.Object
implements java.util.Observer

An abstract ball that moves in a line with its given velocity and bounces off the walls of a rectangularly shaped container. Has a Point representing its center, an int representing its radius, a Point representing its velocity, a Color representing its color.

Field Summary

Fields

Modifier and Type	Field and Description
private java.awt.Color	_color The color of the ball.
private java.awt.Component	_container The Container that is currently holding this ball and defines where the walls are
private java.awt.Point	_location The present location of the center of the ball.
private IPaintStrategy	_paintStrategy The strategy used to paint the ball.
private int	_radius The radius of the ball.
private IUpdateStrategy	_updateStrategy The strategy used to update the state of the ball
private java.awt.Point	_velocity The current velocity of the ball.

Constructor Summary

Constructors

Constructor and Description
Ball(java.awt.Point p, int r, java.awt.Point v, java.awt.Color c, java.awt.Component container, IUpdateStrategy updateStrategy, IPaintStrategy paintStrategy) Initializes this Ball to a given center, radius, color, containing walls, and the NullStrategy to move in a straight line.

Method Summary

Methods

Modifier and Type	Method and Description
void	bounce() Checks if the ball needs to bounce off the wall of its container
java.awt.Color	getColor() Returns the current color of this Ball.
java.awt.Component	getContainer() Accessor for the ball's container Component
java.awt.Point	getLocation() Returns the current center of this Ball.
IPaintStrategy	getPaintStrategy() Returns the current paint strategy of this Ball
int	getRadius() Returns the current radius for this Ball.
IUpdateStrategy	getUpdateStrategy() Returns the current strategy of this Ball
java.awt.Point	getVelocity() Returns the current velocity of this Ball.
void	move() Moves the ball's location by the X and Y increments specified by the velocity property.
void	paint(java.awt.Graphics g) Paints the image of the ball onto a Graphics object.
void	setColor(java.awt.Color color) Sets the color of this Ball to a given color.
void	setLocation(java.awt.Point location) Sets the center to a new location.
void	setPaintStrategy(IPaintStrategy pstrategy) Sets the current strategy of this Ball to the given strategy
void	setRadius(int radius) Sets the radius of this Ball to a new radius.
void	setUpdateStrategy(IUpdateStrategy strategy) Sets the current strategy of this Ball to the given strategy
void	setVelocity(java.awt.Point velocity) Sets the velocity of this Ball to a new velocity.
void	update(java.util.Observable o, java.lang.Object cmd) Run the given command.
void	updateState() Update the state of the ball.

Methods inherited from class java.lang.Object

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

Field Detail

_location

private java.awt.Point _location

The present location of the center of the ball.

_radius

private int _radius

The radius of the ball.

_velocity

private java.awt.Point _velocity

The current velocity of the ball. Given in terms of an X and Y increment per update interval.

_color

private java.awt.Color _color

The color of the ball.

_container

private java.awt.Component _container

The Container that is currently holding this ball and defines where the walls are

_updateStrategy

private IUpdateStrategy _updateStrategy

The strategy used to update the state of the ball

_paintStrategy

private IPaintStrategy _paintStrategy

The strategy used to paint the ball.

Constructor Detail

Ball

public Ball(java.awt.Point p,
    int r,
    java.awt.Point v,
    java.awt.Color c,
    java.awt.Component container,
    IUpdateStrategy updateStrategy,
    IPaintStrategy paintStrategy)

Initializes this Ball to a given center, radius, color, containing walls, and the NullStrategy to move in a straight line.

Parameters:

r - the initial radius of this Ball.

v - the initial velocity of this Ball.

c - The initial color of the ball.

p - the initial center of this Ball.

container - the rectangular Container area where this Ball is drawn.

Method Detail

update

public void update(java.util.Observable o,
          java.lang.Object cmd)

Run the given command.

Specified by:

update in interface java.util.Observer

Parameters:

cmd - The command to run in this context.

updateState

public void updateState()

Update the state of the ball. Delegates to the update strategy.

move

public void move()

Moves the ball's location by the X and Y increments specified by the velocity property.

bounce

public void bounce()

Checks if the ball needs to bounce off the wall of its container

setLocation

public void setLocation(java.awt.Point location)

Sets the center to a new location.

Parameters:

location - the new center.

getLocation

public java.awt.Point getLocation()

Returns the current center of this Ball.

Returns:

a Point representing the center of this Ball.

setRadius

public void setRadius(int radius)

Sets the radius of this Ball to a new radius.

Parameters:

radius -

getRadius

public int getRadius()

Returns the current radius for this Ball.

Returns:

the radius of this Ball.

setVelocity

public void setVelocity(java.awt.Point velocity)

Sets the velocity of this Ball to a new velocity.

Parameters:

velocity - the new velocity for this Ball.

getVelocity

public java.awt.Point getVelocity()

Returns the current velocity of this Ball.

Returns:

the current velocity of this Ball.

setColor

public void setColor(java.awt.Color color)

Sets the color of this Ball to a given color.

Parameters:

color - the new color for this Ball.

getColor

public java.awt.Color getColor()

Returns the current color of this Ball.

Returns:

the color of this Ball.

getUpdateStrategy

public IUpdateStrategy getUpdateStrategy()

Returns the current strategy of this Ball

Returns:

the IUpdateStrategy currently in use.

setUpdateStrategy

public void setUpdateStrategy(IUpdateStrategy strategy)

Sets the current strategy of this Ball to the given strategy

Parameters:

strategy - The new IUpdateStrategy to use.

paint

public void paint(java.awt.Graphics g)

Paints the image of the ball onto a Graphics object. Delegates to the paint strategy.

Parameters:

g - a Graphics object.

setPaintStrategy

public void setPaintStrategy(IPaintStrategy pstrategy)

Sets the current strategy of this Ball to the given strategy

Parameters:

pstrategy - The new IPaintStrategy to use.

getPaintStrategy

public IPaintStrategy getPaintStrategy()

Returns the current paint strategy of this Ball

Returns:

the IPaintStrategy currently in use.

getContainer

public java.awt.Component getContainer()

Accessor for the ball's container Component

Returns:

the ball's container