com.collegeboard.gridworld.actor
Class Actor

java.lang.Object
  com.collegeboard.gridworld.actor.Actor

Direct Known Subclasses:

Alien, Critter, Flower, Rock

public abstract class Actor
extends Object

An Actor is an entity with a color and direction that can act.

copyright© 2005 Cay S. Horstmann (http://horstmann.com)

Author:

Cay Horstmann

Constructor Summary

Actor()
Constructs a black actor that is facing north.

Method Summary

abstract void	act() Override this method to define the action of this actor.
Color	getColor() Gets the color of this actor.
int	getDirection() Gets the current direction of this actor.
Grid<Actor>	getGrid() Gets the grid in which this actor is located
Location	getLocation() Gets the location of this actor Precondition: This actor is in a grid
void	moveTo(Location newLocation) Moves this actor to a new location.
void	putSelfInGrid(Grid<Actor> gr, Location loc) Puts this actor into a grid.
void	removeSelfFromGrid() Removes an actor from a grid.
void	setColor(Color newColor) Sets the color of this actor.
String	toString()
void	turnBy(int angle) Turns the direction of this actor.

Methods inherited from class java.lang.Object

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

Constructor Detail

Actor

public Actor()

Constructs a black actor that is facing north.

Method Detail

act

public abstract void act()

Override this method to define the action of this actor.

getLocation

public Location getLocation()

Gets the location of this actor
Precondition: This actor is in a grid

Returns:

this actor's location

getGrid

public Grid<Actor> getGrid()

Gets the grid in which this actor is located

Returns:

the grid, or null if this actor is not contained in a grid

putSelfInGrid

public void putSelfInGrid(Grid<Actor> gr,
                          Location loc)

Puts this actor into a grid. If there is another actor at the given location, it is removed.
Precondition: This actor is not in a grid

Parameters:

gr - the grid into which this actor should be placed

loc - the location into which the actor should be placed (must be valid)

removeSelfFromGrid

public void removeSelfFromGrid()

Removes an actor from a grid.
Precondition: This actor has been put in a grid.

moveTo

public void moveTo(Location newLocation)

Moves this actor to a new location. If there is another actor at the given location, it is removed.
Precondition: This actor has been put in a grid

Parameters:

newLocation - the new location (must be valid)

turnBy

public void turnBy(int angle)

Turns the direction of this actor.

Parameters:

angle - the angle (clockwise) by which to turn

getDirection

public int getDirection()

Gets the current direction of this actor.

Returns:

the direction in { 0, 1, ..., 359 }

getColor

public Color getColor()

Gets the color of this actor.

Returns:

the color

setColor

public void setColor(Color newColor)

Sets the color of this actor.

Parameters:

newColor - the new color

toString

public String toString()

Overrides:

toString in class Object